1 00:00:10,340 --> 00:00:13,910 with the advent of space technology new 2 00:00:13,910 --> 00:00:13,920 with the advent of space technology new 3 00:00:13,920 --> 00:00:15,709 with the advent of space technology new opportunities are emerging for 4 00:00:15,709 --> 00:00:15,719 opportunities are emerging for 5 00:00:15,719 --> 00:00:18,080 opportunities are emerging for scientific research with exciting 6 00:00:18,080 --> 00:00:18,090 scientific research with exciting 7 00:00:18,090 --> 00:00:21,080 scientific research with exciting applications in many fields to take 8 00:00:21,080 --> 00:00:21,090 applications in many fields to take 9 00:00:21,090 --> 00:00:23,060 applications in many fields to take advantage of this new era in space 10 00:00:23,060 --> 00:00:23,070 advantage of this new era in space 11 00:00:23,070 --> 00:00:26,000 advantage of this new era in space exploration basic research into the 12 00:00:26,000 --> 00:00:26,010 exploration basic research into the 13 00:00:26,010 --> 00:00:27,800 exploration basic research into the fundamental characteristics of the 14 00:00:27,800 --> 00:00:27,810 fundamental characteristics of the 15 00:00:27,810 --> 00:00:30,220 fundamental characteristics of the environment of space such as long-term 16 00:00:30,220 --> 00:00:30,230 environment of space such as long-term 17 00:00:30,230 --> 00:00:32,889 environment of space such as long-term microgravity and ultra-high vacuum 18 00:00:32,889 --> 00:00:32,899 microgravity and ultra-high vacuum 19 00:00:32,899 --> 00:00:37,130 microgravity and ultra-high vacuum should first be undertaken the purpose 20 00:00:37,130 --> 00:00:37,140 should first be undertaken the purpose 21 00:00:37,140 --> 00:00:39,170 should first be undertaken the purpose of the research presented in this video 22 00:00:39,170 --> 00:00:39,180 of the research presented in this video 23 00:00:39,180 --> 00:00:41,330 of the research presented in this video is to understand more clearly the 24 00:00:41,330 --> 00:00:41,340 is to understand more clearly the 25 00:00:41,340 --> 00:00:44,000 is to understand more clearly the effects of surface tension on fluid 26 00:00:44,000 --> 00:00:44,010 effects of surface tension on fluid 27 00:00:44,010 --> 00:00:46,850 effects of surface tension on fluid convection the predominance of surface 28 00:00:46,850 --> 00:00:46,860 convection the predominance of surface 29 00:00:46,860 --> 00:00:49,760 convection the predominance of surface tension effects over buoyancy effects is 30 00:00:49,760 --> 00:00:49,770 tension effects over buoyancy effects is 31 00:00:49,770 --> 00:00:52,459 tension effects over buoyancy effects is a unique characteristic of microgravity 32 00:00:52,459 --> 00:00:52,469 a unique characteristic of microgravity 33 00:00:52,469 --> 00:00:55,160 a unique characteristic of microgravity environments and is critically important 34 00:00:55,160 --> 00:00:55,170 environments and is critically important 35 00:00:55,170 --> 00:00:58,099 environments and is critically important to many microgravity applications such 36 00:00:58,099 --> 00:00:58,109 to many microgravity applications such 37 00:00:58,109 --> 00:01:00,349 to many microgravity applications such as material processing and fluid 38 00:01:00,349 --> 00:01:00,359 as material processing and fluid 39 00:01:00,359 --> 00:01:04,039 as material processing and fluid management the fluid system chosen for 40 00:01:04,039 --> 00:01:04,049 management the fluid system chosen for 41 00:01:04,049 --> 00:01:06,590 management the fluid system chosen for this study the liquid sessile droplet 42 00:01:06,590 --> 00:01:06,600 this study the liquid sessile droplet 43 00:01:06,600 --> 00:01:09,380 this study the liquid sessile droplet has been selected because among many 44 00:01:09,380 --> 00:01:09,390 has been selected because among many 45 00:01:09,390 --> 00:01:11,840 has been selected because among many fluid systems most affected by surface 46 00:01:11,840 --> 00:01:11,850 fluid systems most affected by surface 47 00:01:11,850 --> 00:01:14,600 fluid systems most affected by surface tension liquid droplets are particularly 48 00:01:14,600 --> 00:01:14,610 tension liquid droplets are particularly 49 00:01:14,610 --> 00:01:16,640 tension liquid droplets are particularly important to many industrial and 50 00:01:16,640 --> 00:01:16,650 important to many industrial and 51 00:01:16,650 --> 00:01:20,660 important to many industrial and biological processes evaporation induced 52 00:01:20,660 --> 00:01:20,670 biological processes evaporation induced 53 00:01:20,670 --> 00:01:22,969 biological processes evaporation induced surface tension effects on liquid 54 00:01:22,969 --> 00:01:22,979 surface tension effects on liquid 55 00:01:22,979 --> 00:01:25,520 surface tension effects on liquid droplets and their associated transport 56 00:01:25,520 --> 00:01:25,530 droplets and their associated transport 57 00:01:25,530 --> 00:01:28,730 droplets and their associated transport process can significantly enhance heat 58 00:01:28,730 --> 00:01:28,740 process can significantly enhance heat 59 00:01:28,740 --> 00:01:31,149 process can significantly enhance heat and mass transfer 60 00:01:31,149 --> 00:01:31,159 and mass transfer 61 00:01:31,159 --> 00:01:33,679 and mass transfer they are also critical to a wide range 62 00:01:33,679 --> 00:01:33,689 they are also critical to a wide range 63 00:01:33,689 --> 00:01:36,710 they are also critical to a wide range of technologies such as single crystal 64 00:01:36,710 --> 00:01:36,720 of technologies such as single crystal 65 00:01:36,720 --> 00:01:39,260 of technologies such as single crystal growth the spray drying and cooling of 66 00:01:39,260 --> 00:01:39,270 growth the spray drying and cooling of 67 00:01:39,270 --> 00:01:41,990 growth the spray drying and cooling of metal and the advanced droplet radiators 68 00:01:41,990 --> 00:01:42,000 metal and the advanced droplet radiators 69 00:01:42,000 --> 00:01:44,649 metal and the advanced droplet radiators of the space stations power systems 70 00:01:44,649 --> 00:01:44,659 of the space stations power systems 71 00:01:44,659 --> 00:01:47,690 of the space stations power systems while quantitative research on surface 72 00:01:47,690 --> 00:01:47,700 while quantitative research on surface 73 00:01:47,700 --> 00:01:50,359 while quantitative research on surface tension induced flow is pivotal to our 74 00:01:50,359 --> 00:01:50,369 tension induced flow is pivotal to our 75 00:01:50,369 --> 00:01:51,830 tension induced flow is pivotal to our understanding of the microgravity 76 00:01:51,830 --> 00:01:51,840 understanding of the microgravity 77 00:01:51,840 --> 00:01:54,469 understanding of the microgravity environment it is difficult to achieve 78 00:01:54,469 --> 00:01:54,479 environment it is difficult to achieve 79 00:01:54,479 --> 00:01:57,800 environment it is difficult to achieve on earth not only do surface tension 80 00:01:57,800 --> 00:01:57,810 on earth not only do surface tension 81 00:01:57,810 --> 00:01:59,929 on earth not only do surface tension driven flow phenomena take place solely 82 00:01:59,929 --> 00:01:59,939 driven flow phenomena take place solely 83 00:01:59,939 --> 00:02:02,569 driven flow phenomena take place solely in small-scale systems under normal 84 00:02:02,569 --> 00:02:02,579 in small-scale systems under normal 85 00:02:02,579 --> 00:02:04,429 in small-scale systems under normal gravity surface tension properties 86 00:02:04,429 --> 00:02:04,439 gravity surface tension properties 87 00:02:04,439 --> 00:02:07,550 gravity surface tension properties themselves are very easily disturbed by 88 00:02:07,550 --> 00:02:07,560 themselves are very easily disturbed by 89 00:02:07,560 --> 00:02:09,699 themselves are very easily disturbed by experimental observation 90 00:02:09,699 --> 00:02:09,709 experimental observation 91 00:02:09,709 --> 00:02:13,190 experimental observation thus computational simulations 92 00:02:13,190 --> 00:02:13,200 thus computational simulations 93 00:02:13,200 --> 00:02:15,559 thus computational simulations offer an attractive way to investigate 94 00:02:15,559 --> 00:02:15,569 offer an attractive way to investigate 95 00:02:15,569 --> 00:02:18,140 offer an attractive way to investigate internal convection within liquid 96 00:02:18,140 --> 00:02:18,150 internal convection within liquid 97 00:02:18,150 --> 00:02:21,110 internal convection within liquid droplets during this video a 98 00:02:21,110 --> 00:02:21,120 droplets during this video a 99 00:02:21,120 --> 00:02:23,360 droplets during this video a cross-sectional representation of the 100 00:02:23,360 --> 00:02:23,370 cross-sectional representation of the 101 00:02:23,370 --> 00:02:25,880 cross-sectional representation of the hemispherical liquid droplet under ideal 102 00:02:25,880 --> 00:02:25,890 hemispherical liquid droplet under ideal 103 00:02:25,890 --> 00:02:29,089 hemispherical liquid droplet under ideal conditions is used to show internal 104 00:02:29,089 --> 00:02:29,099 conditions is used to show internal 105 00:02:29,099 --> 00:02:32,990 conditions is used to show internal fluid motion the droplet is placed on an 106 00:02:32,990 --> 00:02:33,000 fluid motion the droplet is placed on an 107 00:02:33,000 --> 00:02:35,300 fluid motion the droplet is placed on an unheated plate with evaporation 108 00:02:35,300 --> 00:02:35,310 unheated plate with evaporation 109 00:02:35,310 --> 00:02:37,910 unheated plate with evaporation occurring along the free surface the 110 00:02:37,910 --> 00:02:37,920 occurring along the free surface the 111 00:02:37,920 --> 00:02:40,009 occurring along the free surface the black dots within the liquid droplet are 112 00:02:40,009 --> 00:02:40,019 black dots within the liquid droplet are 113 00:02:40,019 --> 00:02:43,280 black dots within the liquid droplet are fluid tracers used to visualize fluid 114 00:02:43,280 --> 00:02:43,290 fluid tracers used to visualize fluid 115 00:02:43,290 --> 00:02:46,490 fluid tracers used to visualize fluid flow because the processes that occur 116 00:02:46,490 --> 00:02:46,500 flow because the processes that occur 117 00:02:46,500 --> 00:02:50,210 flow because the processes that occur are assumed symmetric with respect to 118 00:02:50,210 --> 00:02:50,220 are assumed symmetric with respect to 119 00:02:50,220 --> 00:02:52,339 are assumed symmetric with respect to the centerline we will be describing 120 00:02:52,339 --> 00:02:52,349 the centerline we will be describing 121 00:02:52,349 --> 00:02:54,770 the centerline we will be describing only the flow field in the right half of 122 00:02:54,770 --> 00:02:54,780 only the flow field in the right half of 123 00:02:54,780 --> 00:02:58,699 only the flow field in the right half of the droplet two types of evaporation 124 00:02:58,699 --> 00:02:58,709 the droplet two types of evaporation 125 00:02:58,709 --> 00:03:01,250 the droplet two types of evaporation induced convection are presented one 126 00:03:01,250 --> 00:03:01,260 induced convection are presented one 127 00:03:01,260 --> 00:03:03,920 induced convection are presented one under normal gravity where buoyancy is 128 00:03:03,920 --> 00:03:03,930 under normal gravity where buoyancy is 129 00:03:03,930 --> 00:03:06,470 under normal gravity where buoyancy is the most significant force the other 130 00:03:06,470 --> 00:03:06,480 the most significant force the other 131 00:03:06,480 --> 00:03:09,199 the most significant force the other under microgravity where buoyancy force 132 00:03:09,199 --> 00:03:09,209 under microgravity where buoyancy force 133 00:03:09,209 --> 00:03:11,930 under microgravity where buoyancy force subsides and surface tension effects 134 00:03:11,930 --> 00:03:11,940 subsides and surface tension effects 135 00:03:11,940 --> 00:03:15,500 subsides and surface tension effects predominate the patterns of flow that 136 00:03:15,500 --> 00:03:15,510 predominate the patterns of flow that 137 00:03:15,510 --> 00:03:17,140 predominate the patterns of flow that described them were obtained 138 00:03:17,140 --> 00:03:17,150 described them were obtained 139 00:03:17,150 --> 00:03:20,050 described them were obtained computationally using an Adi scheme 140 00:03:20,050 --> 00:03:20,060 computationally using an Adi scheme 141 00:03:20,060 --> 00:03:23,210 computationally using an Adi scheme while a runga cotta scheme tracks the 142 00:03:23,210 --> 00:03:23,220 while a runga cotta scheme tracks the 143 00:03:23,220 --> 00:03:25,879 while a runga cotta scheme tracks the motion of the fluid tracers the 144 00:03:25,879 --> 00:03:25,889 motion of the fluid tracers the 145 00:03:25,889 --> 00:03:28,160 motion of the fluid tracers the calculations required about one hour of 146 00:03:28,160 --> 00:03:28,170 calculations required about one hour of 147 00:03:28,170 --> 00:03:34,430 calculations required about one hour of CPU time on the Cray XMP 24in buoyancy 148 00:03:34,430 --> 00:03:34,440 CPU time on the Cray XMP 24in buoyancy 149 00:03:34,440 --> 00:03:36,559 CPU time on the Cray XMP 24in buoyancy induced convection otherwise known as 150 00:03:36,559 --> 00:03:36,569 induced convection otherwise known as 151 00:03:36,569 --> 00:03:39,410 induced convection otherwise known as Rayleigh convection gravity is the 152 00:03:39,410 --> 00:03:39,420 Rayleigh convection gravity is the 153 00:03:39,420 --> 00:03:43,210 Rayleigh convection gravity is the dominant force in stratified fluids 154 00:03:43,210 --> 00:03:43,220 dominant force in stratified fluids 155 00:03:43,220 --> 00:03:46,039 dominant force in stratified fluids stability exists when heavier fluids 156 00:03:46,039 --> 00:03:46,049 stability exists when heavier fluids 157 00:03:46,049 --> 00:03:49,190 stability exists when heavier fluids live beneath lighter fluids that is why 158 00:03:49,190 --> 00:03:49,200 live beneath lighter fluids that is why 159 00:03:49,200 --> 00:03:51,140 live beneath lighter fluids that is why when a heavier fluid lies above a 160 00:03:51,140 --> 00:03:51,150 when a heavier fluid lies above a 161 00:03:51,150 --> 00:03:53,660 when a heavier fluid lies above a lighter one the heavier fluid will tend 162 00:03:53,660 --> 00:03:53,670 lighter one the heavier fluid will tend 163 00:03:53,670 --> 00:03:56,210 lighter one the heavier fluid will tend to descend when the criteria for 164 00:03:56,210 --> 00:03:56,220 to descend when the criteria for 165 00:03:56,220 --> 00:03:59,000 to descend when the criteria for stability are exceeded the result will 166 00:03:59,000 --> 00:03:59,010 stability are exceeded the result will 167 00:03:59,010 --> 00:04:03,220 stability are exceeded the result will be fluid motion induced by gravity we 168 00:04:03,220 --> 00:04:03,230 be fluid motion induced by gravity we 169 00:04:03,230 --> 00:04:06,440 be fluid motion induced by gravity we begin with a liquid droplet having a 170 00:04:06,440 --> 00:04:06,450 begin with a liquid droplet having a 171 00:04:06,450 --> 00:04:08,750 begin with a liquid droplet having a uniform temperature shown in orange 172 00:04:08,750 --> 00:04:08,760 uniform temperature shown in orange 173 00:04:08,760 --> 00:04:11,240 uniform temperature shown in orange which is the same as the plate upon 174 00:04:11,240 --> 00:04:11,250 which is the same as the plate upon 175 00:04:11,250 --> 00:04:14,150 which is the same as the plate upon which it rests as evaporative cooling 176 00:04:14,150 --> 00:04:14,160 which it rests as evaporative cooling 177 00:04:14,160 --> 00:04:16,759 which it rests as evaporative cooling occurs along the free surface of the 178 00:04:16,759 --> 00:04:16,769 occurs along the free surface of the 179 00:04:16,769 --> 00:04:19,150 occurs along the free surface of the drop the temperature of that surface 180 00:04:19,150 --> 00:04:19,160 drop the temperature of that surface 181 00:04:19,160 --> 00:04:22,009 drop the temperature of that surface decreases which makes the fluid there 182 00:04:22,009 --> 00:04:22,019 decreases which makes the fluid there 183 00:04:22,019 --> 00:04:26,600 decreases which makes the fluid there heavier as evaporation proceeds the 184 00:04:26,600 --> 00:04:26,610 heavier as evaporation proceeds the 185 00:04:26,610 --> 00:04:29,450 heavier as evaporation proceeds the temperature continues to decrease and a 186 00:04:29,450 --> 00:04:29,460 temperature continues to decrease and a 187 00:04:29,460 --> 00:04:32,029 temperature continues to decrease and a yellow rim representing the colder fluid 188 00:04:32,029 --> 00:04:32,039 yellow rim representing the colder fluid 189 00:04:32,039 --> 00:04:35,209 yellow rim representing the colder fluid at the surface broadens eventually as 190 00:04:35,209 --> 00:04:35,219 at the surface broadens eventually as 191 00:04:35,219 --> 00:04:37,490 at the surface broadens eventually as the fluid turns even colder the rim 192 00:04:37,490 --> 00:04:37,500 the fluid turns even colder the rim 193 00:04:37,500 --> 00:04:41,240 the fluid turns even colder the rim becomes green and then blue as this 194 00:04:41,240 --> 00:04:41,250 becomes green and then blue as this 195 00:04:41,250 --> 00:04:44,240 becomes green and then blue as this increasingly heavier fluid descends the 196 00:04:44,240 --> 00:04:44,250 increasingly heavier fluid descends the 197 00:04:44,250 --> 00:04:46,580 increasingly heavier fluid descends the relatively warmer fluid of the interior 198 00:04:46,580 --> 00:04:46,590 relatively warmer fluid of the interior 199 00:04:46,590 --> 00:04:49,760 relatively warmer fluid of the interior ascends setting up a clockwise fluid 200 00:04:49,760 --> 00:04:49,770 ascends setting up a clockwise fluid 201 00:04:49,770 --> 00:04:53,209 ascends setting up a clockwise fluid convection because buoyancy force is a 202 00:04:53,209 --> 00:04:53,219 convection because buoyancy force is a 203 00:04:53,219 --> 00:04:56,450 convection because buoyancy force is a body force it induces a global motion 204 00:04:56,450 --> 00:04:56,460 body force it induces a global motion 205 00:04:56,460 --> 00:04:59,209 body force it induces a global motion and convection occurs almost everywhere 206 00:04:59,209 --> 00:04:59,219 and convection occurs almost everywhere 207 00:04:59,219 --> 00:05:02,689 and convection occurs almost everywhere within the liquid drop after an 208 00:05:02,689 --> 00:05:02,699 within the liquid drop after an 209 00:05:02,699 --> 00:05:05,089 within the liquid drop after an initially rapid flow the rate of 210 00:05:05,089 --> 00:05:05,099 initially rapid flow the rate of 211 00:05:05,099 --> 00:05:08,330 initially rapid flow the rate of convection gradually slows down as the 212 00:05:08,330 --> 00:05:08,340 convection gradually slows down as the 213 00:05:08,340 --> 00:05:10,010 convection gradually slows down as the temperature field becomes vertically 214 00:05:10,010 --> 00:05:10,020 temperature field becomes vertically 215 00:05:10,020 --> 00:05:12,920 temperature field becomes vertically more stable the clockwise fluid motion 216 00:05:12,920 --> 00:05:12,930 more stable the clockwise fluid motion 217 00:05:12,930 --> 00:05:15,409 more stable the clockwise fluid motion in the upper layer is reduced and it 218 00:05:15,409 --> 00:05:15,419 in the upper layer is reduced and it 219 00:05:15,419 --> 00:05:18,350 in the upper layer is reduced and it almost still predominantly lateral 220 00:05:18,350 --> 00:05:18,360 almost still predominantly lateral 221 00:05:18,360 --> 00:05:26,390 almost still predominantly lateral motion results eventually however as 222 00:05:26,390 --> 00:05:26,400 motion results eventually however as 223 00:05:26,400 --> 00:05:28,790 motion results eventually however as evaporative cooling continues to reduce 224 00:05:28,790 --> 00:05:28,800 evaporative cooling continues to reduce 225 00:05:28,800 --> 00:05:30,730 evaporative cooling continues to reduce the temperature at the surface a 226 00:05:30,730 --> 00:05:30,740 the temperature at the surface a 227 00:05:30,740 --> 00:05:33,680 the temperature at the surface a coupling between internal convection and 228 00:05:33,680 --> 00:05:33,690 coupling between internal convection and 229 00:05:33,690 --> 00:05:37,159 coupling between internal convection and that cooling induces to thermal 230 00:05:37,159 --> 00:05:37,169 that cooling induces to thermal 231 00:05:37,169 --> 00:05:38,439 that cooling induces to thermal stratifications 232 00:05:38,439 --> 00:05:38,449 stratifications 233 00:05:38,449 --> 00:05:41,450 stratifications the first stratification moves clockwise 234 00:05:41,450 --> 00:05:41,460 the first stratification moves clockwise 235 00:05:41,460 --> 00:05:44,200 the first stratification moves clockwise at the lower edge of the droplet surface 236 00:05:44,200 --> 00:05:44,210 at the lower edge of the droplet surface 237 00:05:44,210 --> 00:05:47,659 at the lower edge of the droplet surface the second moves counterclockwise and 238 00:05:47,659 --> 00:05:47,669 the second moves counterclockwise and 239 00:05:47,669 --> 00:05:49,999 the second moves counterclockwise and begins at the top of the surface as 240 00:05:49,999 --> 00:05:50,009 begins at the top of the surface as 241 00:05:50,009 --> 00:05:52,790 begins at the top of the surface as another vortex of cooler fluid moves 242 00:05:52,790 --> 00:05:52,800 another vortex of cooler fluid moves 243 00:05:52,800 --> 00:05:56,059 another vortex of cooler fluid moves downward into the interior demonstrating 244 00:05:56,059 --> 00:05:56,069 downward into the interior demonstrating 245 00:05:56,069 --> 00:05:58,339 downward into the interior demonstrating that evaporation induced buoyancy 246 00:05:58,339 --> 00:05:58,349 that evaporation induced buoyancy 247 00:05:58,349 --> 00:06:03,159 that evaporation induced buoyancy convection is a dynamic unsteady process 248 00:06:03,159 --> 00:06:03,169 convection is a dynamic unsteady process 249 00:06:03,169 --> 00:06:06,709 convection is a dynamic unsteady process unlike buoyancy dominant flow surface 250 00:06:06,709 --> 00:06:06,719 unlike buoyancy dominant flow surface 251 00:06:06,719 --> 00:06:09,110 unlike buoyancy dominant flow surface tension dominant flow has not been well 252 00:06:09,110 --> 00:06:09,120 tension dominant flow has not been well 253 00:06:09,120 --> 00:06:12,469 tension dominant flow has not been well studied however we do know that it is 254 00:06:12,469 --> 00:06:12,479 studied however we do know that it is 255 00:06:12,479 --> 00:06:15,010 studied however we do know that it is partly a function of temperature and 256 00:06:15,010 --> 00:06:15,020 partly a function of temperature and 257 00:06:15,020 --> 00:06:19,579 partly a function of temperature and concentration the present study focuses 258 00:06:19,579 --> 00:06:19,589 concentration the present study focuses 259 00:06:19,589 --> 00:06:21,649 concentration the present study focuses on the effect of temperature on surface 260 00:06:21,649 --> 00:06:21,659 on the effect of temperature on surface 261 00:06:21,659 --> 00:06:24,800 on the effect of temperature on surface tension the warmer the fluid the weaker 262 00:06:24,800 --> 00:06:24,810 tension the warmer the fluid the weaker 263 00:06:24,810 --> 00:06:28,129 tension the warmer the fluid the weaker the surface tension and conversely the 264 00:06:28,129 --> 00:06:28,139 the surface tension and conversely the 265 00:06:28,139 --> 00:06:30,379 the surface tension and conversely the colder the fluid the stronger the 266 00:06:30,379 --> 00:06:30,389 colder the fluid the stronger the 267 00:06:30,389 --> 00:06:34,129 colder the fluid the stronger the surface tension again we begin with a 268 00:06:34,129 --> 00:06:34,139 surface tension again we begin with a 269 00:06:34,139 --> 00:06:36,290 surface tension again we begin with a liquid droplet having a uniform 270 00:06:36,290 --> 00:06:36,300 liquid droplet having a uniform 271 00:06:36,300 --> 00:06:38,540 liquid droplet having a uniform temperature which is the same as the 272 00:06:38,540 --> 00:06:38,550 temperature which is the same as the 273 00:06:38,550 --> 00:06:40,310 temperature which is the same as the plate upon which it rests 274 00:06:40,310 --> 00:06:40,320 plate upon which it rests 275 00:06:40,320 --> 00:06:44,120 plate upon which it rests as evaporative cooling occurs along the 276 00:06:44,120 --> 00:06:44,130 as evaporative cooling occurs along the 277 00:06:44,130 --> 00:06:46,610 as evaporative cooling occurs along the droplets free surface the temperature 278 00:06:46,610 --> 00:06:46,620 droplets free surface the temperature 279 00:06:46,620 --> 00:06:49,310 droplets free surface the temperature there decreases shown here by the 280 00:06:49,310 --> 00:06:49,320 there decreases shown here by the 281 00:06:49,320 --> 00:06:52,100 there decreases shown here by the broadening yellow rim and it's gradual 282 00:06:52,100 --> 00:06:52,110 broadening yellow rim and it's gradual 283 00:06:52,110 --> 00:06:55,360 broadening yellow rim and it's gradual transformation from yellow to green 284 00:06:55,360 --> 00:06:55,370 transformation from yellow to green 285 00:06:55,370 --> 00:06:57,800 transformation from yellow to green because the temperature at the bottom of 286 00:06:57,800 --> 00:06:57,810 because the temperature at the bottom of 287 00:06:57,810 --> 00:07:00,200 because the temperature at the bottom of the plate is still warm a temperature 288 00:07:00,200 --> 00:07:00,210 the plate is still warm a temperature 289 00:07:00,210 --> 00:07:02,690 the plate is still warm a temperature gradient begins to form where the plate 290 00:07:02,690 --> 00:07:02,700 gradient begins to form where the plate 291 00:07:02,700 --> 00:07:05,060 gradient begins to form where the plate meets the lower edge of the relatively 292 00:07:05,060 --> 00:07:05,070 meets the lower edge of the relatively 293 00:07:05,070 --> 00:07:08,090 meets the lower edge of the relatively colder droplet the surface tension is 294 00:07:08,090 --> 00:07:08,100 colder droplet the surface tension is 295 00:07:08,100 --> 00:07:10,910 colder droplet the surface tension is weakest near the warm plate but stronger 296 00:07:10,910 --> 00:07:10,920 weakest near the warm plate but stronger 297 00:07:10,920 --> 00:07:13,540 weakest near the warm plate but stronger at the colder surface as a result 298 00:07:13,540 --> 00:07:13,550 at the colder surface as a result 299 00:07:13,550 --> 00:07:15,950 at the colder surface as a result surface tension is able to pull the 300 00:07:15,950 --> 00:07:15,960 surface tension is able to pull the 301 00:07:15,960 --> 00:07:18,560 surface tension is able to pull the fluid upwards that is away from the 302 00:07:18,560 --> 00:07:18,570 fluid upwards that is away from the 303 00:07:18,570 --> 00:07:21,500 fluid upwards that is away from the plate and fluid viscosity transfers 304 00:07:21,500 --> 00:07:21,510 plate and fluid viscosity transfers 305 00:07:21,510 --> 00:07:26,090 plate and fluid viscosity transfers momentum into the interior conservation 306 00:07:26,090 --> 00:07:26,100 momentum into the interior conservation 307 00:07:26,100 --> 00:07:28,190 momentum into the interior conservation of mass dictates that a circular 308 00:07:28,190 --> 00:07:28,200 of mass dictates that a circular 309 00:07:28,200 --> 00:07:31,820 of mass dictates that a circular counterclockwise motion or vortex wraps 310 00:07:31,820 --> 00:07:31,830 counterclockwise motion or vortex wraps 311 00:07:31,830 --> 00:07:34,640 counterclockwise motion or vortex wraps cold fluid into the interior of the drop 312 00:07:34,640 --> 00:07:34,650 cold fluid into the interior of the drop 313 00:07:34,650 --> 00:07:38,780 cold fluid into the interior of the drop to form a cold pocket the end result is 314 00:07:38,780 --> 00:07:38,790 to form a cold pocket the end result is 315 00:07:38,790 --> 00:07:41,750 to form a cold pocket the end result is a self propelling process with a maximum 316 00:07:41,750 --> 00:07:41,760 a self propelling process with a maximum 317 00:07:41,760 --> 00:07:44,300 a self propelling process with a maximum velocity and the largest temperature 318 00:07:44,300 --> 00:07:44,310 velocity and the largest temperature 319 00:07:44,310 --> 00:07:47,390 velocity and the largest temperature gradient coupled in the cold pocket to 320 00:07:47,390 --> 00:07:47,400 gradient coupled in the cold pocket to 321 00:07:47,400 --> 00:07:49,370 gradient coupled in the cold pocket to maintain the surface tension induced 322 00:07:49,370 --> 00:07:49,380 maintain the surface tension induced 323 00:07:49,380 --> 00:07:52,310 maintain the surface tension induced fluid flow which pushes the vortex all 324 00:07:52,310 --> 00:07:52,320 fluid flow which pushes the vortex all 325 00:07:52,320 --> 00:07:55,780 fluid flow which pushes the vortex all the way up the droplets free surface 326 00:07:55,780 --> 00:07:55,790 the way up the droplets free surface 327 00:07:55,790 --> 00:07:59,150 the way up the droplets free surface let's compare our computational results 328 00:07:59,150 --> 00:07:59,160 let's compare our computational results 329 00:07:59,160 --> 00:08:00,940 let's compare our computational results with what we observe experimentally 330 00:08:00,940 --> 00:08:00,950 with what we observe experimentally 331 00:08:00,950 --> 00:08:04,840 with what we observe experimentally using laser shadowgraph 332 00:08:04,840 --> 00:08:04,850 using laser shadowgraph 333 00:08:04,850 --> 00:08:08,120 using laser shadowgraph traces of aluminum particles allow us to 334 00:08:08,120 --> 00:08:08,130 traces of aluminum particles allow us to 335 00:08:08,130 --> 00:08:10,820 traces of aluminum particles allow us to visualize evaporation induced convective 336 00:08:10,820 --> 00:08:10,830 visualize evaporation induced convective 337 00:08:10,830 --> 00:08:14,660 visualize evaporation induced convective patterns inside a chloroform drop a few 338 00:08:14,660 --> 00:08:14,670 patterns inside a chloroform drop a few 339 00:08:14,670 --> 00:08:17,030 patterns inside a chloroform drop a few seconds after it was placed on an 340 00:08:17,030 --> 00:08:17,040 seconds after it was placed on an 341 00:08:17,040 --> 00:08:21,470 seconds after it was placed on an isothermal plate for regions of flow can 342 00:08:21,470 --> 00:08:21,480 isothermal plate for regions of flow can 343 00:08:21,480 --> 00:08:24,950 isothermal plate for regions of flow can be identified region 1 located at the 344 00:08:24,950 --> 00:08:24,960 be identified region 1 located at the 345 00:08:24,960 --> 00:08:28,100 be identified region 1 located at the top of the drop is stagnant region 2 346 00:08:28,100 --> 00:08:28,110 top of the drop is stagnant region 2 347 00:08:28,110 --> 00:08:31,130 top of the drop is stagnant region 2 consists of weak clockwise convection 348 00:08:31,130 --> 00:08:31,140 consists of weak clockwise convection 349 00:08:31,140 --> 00:08:35,180 consists of weak clockwise convection currents driven by buoyancy force region 350 00:08:35,180 --> 00:08:35,190 currents driven by buoyancy force region 351 00:08:35,190 --> 00:08:37,300 currents driven by buoyancy force region 3 is composed of a few layers of 352 00:08:37,300 --> 00:08:37,310 3 is composed of a few layers of 353 00:08:37,310 --> 00:08:41,540 3 is composed of a few layers of hexagonal flow cells finally region 4 354 00:08:41,540 --> 00:08:41,550 hexagonal flow cells finally region 4 355 00:08:41,550 --> 00:08:44,290 hexagonal flow cells finally region 4 has relatively stronger counterclockwise 356 00:08:44,290 --> 00:08:44,300 has relatively stronger counterclockwise 357 00:08:44,300 --> 00:08:46,910 has relatively stronger counterclockwise convection currents which according to 358 00:08:46,910 --> 00:08:46,920 convection currents which according to 359 00:08:46,920 --> 00:08:49,520 convection currents which according to our computational results are driven by 360 00:08:49,520 --> 00:08:49,530 our computational results are driven by 361 00:08:49,530 --> 00:08:53,330 our computational results are driven by surface tension since the liquid drop is 362 00:08:53,330 --> 00:08:53,340 surface tension since the liquid drop is 363 00:08:53,340 --> 00:08:54,020 surface tension since the liquid drop is a small 364 00:08:54,020 --> 00:08:54,030 a small 365 00:08:54,030 --> 00:08:56,990 a small system surface tension is expected to 366 00:08:56,990 --> 00:08:57,000 system surface tension is expected to 367 00:08:57,000 --> 00:08:59,090 system surface tension is expected to play a dominant role in the evaporation 368 00:08:59,090 --> 00:08:59,100 play a dominant role in the evaporation 369 00:08:59,100 --> 00:09:01,820 play a dominant role in the evaporation process and this is also what we observe 370 00:09:01,820 --> 00:09:01,830 process and this is also what we observe 371 00:09:01,830 --> 00:09:05,150 process and this is also what we observe experimentally as evaporation proceeds 372 00:09:05,150 --> 00:09:05,160 experimentally as evaporation proceeds 373 00:09:05,160 --> 00:09:08,210 experimentally as evaporation proceeds the weak buoyancy induced flow region 374 00:09:08,210 --> 00:09:08,220 the weak buoyancy induced flow region 375 00:09:08,220 --> 00:09:10,160 the weak buoyancy induced flow region shrinks while a counter clockwise 376 00:09:10,160 --> 00:09:10,170 shrinks while a counter clockwise 377 00:09:10,170 --> 00:09:13,120 shrinks while a counter clockwise surface tension flow in Region four 378 00:09:13,120 --> 00:09:13,130 surface tension flow in Region four 379 00:09:13,130 --> 00:09:17,090 surface tension flow in Region four displaces Region three upwards this is 380 00:09:17,090 --> 00:09:17,100 displaces Region three upwards this is 381 00:09:17,100 --> 00:09:19,340 displaces Region three upwards this is exactly the result we saw earlier in the 382 00:09:19,340 --> 00:09:19,350 exactly the result we saw earlier in the 383 00:09:19,350 --> 00:09:21,110 exactly the result we saw earlier in the graphical presentation of surface 384 00:09:21,110 --> 00:09:21,120 graphical presentation of surface 385 00:09:21,120 --> 00:09:24,350 graphical presentation of surface tension dominant convection thus the 386 00:09:24,350 --> 00:09:24,360 tension dominant convection thus the 387 00:09:24,360 --> 00:09:26,990 tension dominant convection thus the computational results qualitatively 388 00:09:26,990 --> 00:09:27,000 computational results qualitatively 389 00:09:27,000 --> 00:09:30,430 computational results qualitatively match the experimental results well 390 00:09:30,430 --> 00:09:30,440 match the experimental results well 391 00:09:30,440 --> 00:09:33,590 match the experimental results well however the observations also reveal a 392 00:09:33,590 --> 00:09:33,600 however the observations also reveal a 393 00:09:33,600 --> 00:09:36,740 however the observations also reveal a drawback of the experimental method not 394 00:09:36,740 --> 00:09:36,750 drawback of the experimental method not 395 00:09:36,750 --> 00:09:38,870 drawback of the experimental method not only is the stagnant nature of region 396 00:09:38,870 --> 00:09:38,880 only is the stagnant nature of region 397 00:09:38,880 --> 00:09:41,180 only is the stagnant nature of region one exaggerated by the particles of 398 00:09:41,180 --> 00:09:41,190 one exaggerated by the particles of 399 00:09:41,190 --> 00:09:43,880 one exaggerated by the particles of aluminum that accumulate there but the 400 00:09:43,880 --> 00:09:43,890 aluminum that accumulate there but the 401 00:09:43,890 --> 00:09:46,160 aluminum that accumulate there but the accumulation eventually destroys the 402 00:09:46,160 --> 00:09:46,170 accumulation eventually destroys the 403 00:09:46,170 --> 00:09:49,180 accumulation eventually destroys the surface tension properties altogether 404 00:09:49,180 --> 00:09:49,190 surface tension properties altogether 405 00:09:49,190 --> 00:09:51,650 surface tension properties altogether let's review the graphical presentation 406 00:09:51,650 --> 00:09:51,660 let's review the graphical presentation 407 00:09:51,660 --> 00:09:54,620 let's review the graphical presentation of buoyancy dominant and thermo 408 00:09:54,620 --> 00:09:54,630 of buoyancy dominant and thermo 409 00:09:54,630 --> 00:09:57,530 of buoyancy dominant and thermo capillary dominant convection using 410 00:09:57,530 --> 00:09:57,540 capillary dominant convection using 411 00:09:57,540 --> 00:10:00,260 capillary dominant convection using numerical methods the elapsed time 412 00:10:00,260 --> 00:10:00,270 numerical methods the elapsed time 413 00:10:00,270 --> 00:10:02,330 numerical methods the elapsed time during this segment of the video will 414 00:10:02,330 --> 00:10:02,340 during this segment of the video will 415 00:10:02,340 --> 00:10:04,430 during this segment of the video will more accurately reflect real time 416 00:10:04,430 --> 00:10:04,440 more accurately reflect real time 417 00:10:04,440 --> 00:10:08,180 more accurately reflect real time processes in buoyancy dominant 418 00:10:08,180 --> 00:10:08,190 processes in buoyancy dominant 419 00:10:08,190 --> 00:10:10,850 processes in buoyancy dominant convection gravity is the dominant force 420 00:10:10,850 --> 00:10:10,860 convection gravity is the dominant force 421 00:10:10,860 --> 00:10:14,030 convection gravity is the dominant force as evaporation occurs the temperature at 422 00:10:14,030 --> 00:10:14,040 as evaporation occurs the temperature at 423 00:10:14,040 --> 00:10:16,540 as evaporation occurs the temperature at the droplet surface decreases a 424 00:10:16,540 --> 00:10:16,550 the droplet surface decreases a 425 00:10:16,550 --> 00:10:19,580 the droplet surface decreases a clockwise convection results as the 426 00:10:19,580 --> 00:10:19,590 clockwise convection results as the 427 00:10:19,590 --> 00:10:22,060 clockwise convection results as the increasingly colder and heavier fluid 428 00:10:22,060 --> 00:10:22,070 increasingly colder and heavier fluid 429 00:10:22,070 --> 00:10:25,180 increasingly colder and heavier fluid descends and the relatively warmer fluid 430 00:10:25,180 --> 00:10:25,190 descends and the relatively warmer fluid 431 00:10:25,190 --> 00:10:28,190 descends and the relatively warmer fluid ascends eventually as the rate of 432 00:10:28,190 --> 00:10:28,200 ascends eventually as the rate of 433 00:10:28,200 --> 00:10:30,800 ascends eventually as the rate of convection slows down the clockwise 434 00:10:30,800 --> 00:10:30,810 convection slows down the clockwise 435 00:10:30,810 --> 00:10:33,740 convection slows down the clockwise fluid motion is reduced and lateral 436 00:10:33,740 --> 00:10:33,750 fluid motion is reduced and lateral 437 00:10:33,750 --> 00:10:36,470 fluid motion is reduced and lateral motion predominates until a second 438 00:10:36,470 --> 00:10:36,480 motion predominates until a second 439 00:10:36,480 --> 00:10:42,860 motion predominates until a second counter clockwise motion begins when we 440 00:10:42,860 --> 00:10:42,870 counter clockwise motion begins when we 441 00:10:42,870 --> 00:10:45,080 counter clockwise motion begins when we observe the surface tension dominant 442 00:10:45,080 --> 00:10:45,090 observe the surface tension dominant 443 00:10:45,090 --> 00:10:47,210 observe the surface tension dominant flow characteristics of microgravity 444 00:10:47,210 --> 00:10:47,220 flow characteristics of microgravity 445 00:10:47,220 --> 00:10:49,880 flow characteristics of microgravity environments a different pattern of 446 00:10:49,880 --> 00:10:49,890 environments a different pattern of 447 00:10:49,890 --> 00:10:52,850 environments a different pattern of convection occurs the resulting fluid 448 00:10:52,850 --> 00:10:52,860 convection occurs the resulting fluid 449 00:10:52,860 --> 00:10:54,920 convection occurs the resulting fluid motion is generated by the surface 450 00:10:54,920 --> 00:10:54,930 motion is generated by the surface 451 00:10:54,930 --> 00:10:57,230 motion is generated by the surface tension gradient along the droplet 452 00:10:57,230 --> 00:10:57,240 tension gradient along the droplet 453 00:10:57,240 --> 00:11:00,140 tension gradient along the droplet surface which pulls the fluid upward in 454 00:11:00,140 --> 00:11:00,150 surface which pulls the fluid upward in 455 00:11:00,150 --> 00:11:03,590 surface which pulls the fluid upward in a circular counterclockwise motion the 456 00:11:03,590 --> 00:11:03,600 a circular counterclockwise motion the 457 00:11:03,600 --> 00:11:06,200 a circular counterclockwise motion the end result is a self propelling process 458 00:11:06,200 --> 00:11:06,210 end result is a self propelling process 459 00:11:06,210 --> 00:11:07,940 end result is a self propelling process with velocity and ten 460 00:11:07,940 --> 00:11:07,950 with velocity and ten 461 00:11:07,950 --> 00:11:10,490 with velocity and ten coupled to maintain the surface tension 462 00:11:10,490 --> 00:11:10,500 coupled to maintain the surface tension 463 00:11:10,500 --> 00:11:14,750 coupled to maintain the surface tension induced flow in this video we have seen 464 00:11:14,750 --> 00:11:14,760 induced flow in this video we have seen 465 00:11:14,760 --> 00:11:16,940 induced flow in this video we have seen a direct simulation of natural 466 00:11:16,940 --> 00:11:16,950 a direct simulation of natural 467 00:11:16,950 --> 00:11:20,060 a direct simulation of natural convection inside liquid droplets caused 468 00:11:20,060 --> 00:11:20,070 convection inside liquid droplets caused 469 00:11:20,070 --> 00:11:22,970 convection inside liquid droplets caused by evaporative cooling of the two 470 00:11:22,970 --> 00:11:22,980 by evaporative cooling of the two 471 00:11:22,980 --> 00:11:24,920 by evaporative cooling of the two mechanisms that induce convection 472 00:11:24,920 --> 00:11:24,930 mechanisms that induce convection 473 00:11:24,930 --> 00:11:27,470 mechanisms that induce convection the first was gravitational buoyancy 474 00:11:27,470 --> 00:11:27,480 the first was gravitational buoyancy 475 00:11:27,480 --> 00:11:30,200 the first was gravitational buoyancy force and the resulting fluid transport 476 00:11:30,200 --> 00:11:30,210 force and the resulting fluid transport 477 00:11:30,210 --> 00:11:33,050 force and the resulting fluid transport the well studied rayleigh natural 478 00:11:33,050 --> 00:11:33,060 the well studied rayleigh natural 479 00:11:33,060 --> 00:11:35,510 the well studied rayleigh natural convection the other mechanism which is 480 00:11:35,510 --> 00:11:35,520 convection the other mechanism which is 481 00:11:35,520 --> 00:11:37,310 convection the other mechanism which is less familiar to the thermal fluid 482 00:11:37,310 --> 00:11:37,320 less familiar to the thermal fluid 483 00:11:37,320 --> 00:11:39,560 less familiar to the thermal fluid society but more relevant to future 484 00:11:39,560 --> 00:11:39,570 society but more relevant to future 485 00:11:39,570 --> 00:11:42,860 society but more relevant to future space venture is surface tension induced 486 00:11:42,860 --> 00:11:42,870 space venture is surface tension induced 487 00:11:42,870 --> 00:11:45,320 space venture is surface tension induced by a thermal gradient and the resulting 488 00:11:45,320 --> 00:11:45,330 by a thermal gradient and the resulting 489 00:11:45,330 --> 00:11:48,350 by a thermal gradient and the resulting fluid motion the so called Marangoni or 490 00:11:48,350 --> 00:11:48,360 fluid motion the so called Marangoni or 491 00:11:48,360 --> 00:11:51,680 fluid motion the so called Marangoni or thermo capillary convection the 492 00:11:51,680 --> 00:11:51,690 thermo capillary convection the 493 00:11:51,690 --> 00:11:53,420 thermo capillary convection the fundamental difference is between these 494 00:11:53,420 --> 00:11:53,430 fundamental difference is between these 495 00:11:53,430 --> 00:11:55,340 fundamental difference is between these two convection patterns can be briefly 496 00:11:55,340 --> 00:11:55,350 two convection patterns can be briefly 497 00:11:55,350 --> 00:11:59,210 two convection patterns can be briefly summarized as follows gravitational 498 00:11:59,210 --> 00:11:59,220 summarized as follows gravitational 499 00:11:59,220 --> 00:12:02,300 summarized as follows gravitational buoyancy force is a body force thus the 500 00:12:02,300 --> 00:12:02,310 buoyancy force is a body force thus the 501 00:12:02,310 --> 00:12:05,150 buoyancy force is a body force thus the induced fluid dynamics is global and the 502 00:12:05,150 --> 00:12:05,160 induced fluid dynamics is global and the 503 00:12:05,160 --> 00:12:07,340 induced fluid dynamics is global and the resulting temperature field in the fluid 504 00:12:07,340 --> 00:12:07,350 resulting temperature field in the fluid 505 00:12:07,350 --> 00:12:10,940 resulting temperature field in the fluid is more homogeneous li mixed thermo 506 00:12:10,940 --> 00:12:10,950 is more homogeneous li mixed thermo 507 00:12:10,950 --> 00:12:13,460 is more homogeneous li mixed thermo capillary force is a surface force and 508 00:12:13,460 --> 00:12:13,470 capillary force is a surface force and 509 00:12:13,470 --> 00:12:16,130 capillary force is a surface force and here both the induced fluid motion and 510 00:12:16,130 --> 00:12:16,140 here both the induced fluid motion and 511 00:12:16,140 --> 00:12:18,290 here both the induced fluid motion and the thermal stratification is more 512 00:12:18,290 --> 00:12:18,300 the thermal stratification is more 513 00:12:18,300 --> 00:12:23,210 the thermal stratification is more intensified along the free surface under 514 00:12:23,210 --> 00:12:23,220 intensified along the free surface under 515 00:12:23,220 --> 00:12:26,090 intensified along the free surface under conditions of decreasing gravity the 516 00:12:26,090 --> 00:12:26,100 conditions of decreasing gravity the 517 00:12:26,100 --> 00:12:27,980 conditions of decreasing gravity the pattern of fluid flow will gradually 518 00:12:27,980 --> 00:12:27,990 pattern of fluid flow will gradually 519 00:12:27,990 --> 00:12:30,070 pattern of fluid flow will gradually become less dominated by buoyancy 520 00:12:30,070 --> 00:12:30,080 become less dominated by buoyancy 521 00:12:30,080 --> 00:12:33,410 become less dominated by buoyancy convection eventually when the force of 522 00:12:33,410 --> 00:12:33,420 convection eventually when the force of 523 00:12:33,420 --> 00:12:35,320 convection eventually when the force of gravity has been reduced significantly 524 00:12:35,320 --> 00:12:35,330 gravity has been reduced significantly 525 00:12:35,330 --> 00:12:37,940 gravity has been reduced significantly the flow pattern will be dominated by 526 00:12:37,940 --> 00:12:37,950 the flow pattern will be dominated by 527 00:12:37,950 --> 00:12:42,980 the flow pattern will be dominated by surface tension this research video has 528 00:12:42,980 --> 00:12:42,990 surface tension this research video has 529 00:12:42,990 --> 00:12:44,840 surface tension this research video has illustrated the clear differences 530 00:12:44,840 --> 00:12:44,850 illustrated the clear differences 531 00:12:44,850 --> 00:12:47,240 illustrated the clear differences between two mechanisms of fluid 532 00:12:47,240 --> 00:12:47,250 between two mechanisms of fluid 533 00:12:47,250 --> 00:12:50,150 between two mechanisms of fluid transport thermo capillary convection 534 00:12:50,150 --> 00:12:50,160 transport thermo capillary convection 535 00:12:50,160 --> 00:12:53,750 transport thermo capillary convection and buoyancy dominant convection in the 536 00:12:53,750 --> 00:12:53,760 and buoyancy dominant convection in the 537 00:12:53,760 --> 00:12:56,330 and buoyancy dominant convection in the future the investigator will expand his 538 00:12:56,330 --> 00:12:56,340 future the investigator will expand his 539 00:12:56,340 --> 00:12:58,730 future the investigator will expand his studies of fluid flow to explore the 540 00:12:58,730 --> 00:12:58,740 studies of fluid flow to explore the 541 00:12:58,740 --> 00:13:00,980 studies of fluid flow to explore the effects of surface tension on double 542 00:13:00,980 --> 00:13:00,990 effects of surface tension on double 543 00:13:00,990 --> 00:13:03,860 effects of surface tension on double diffusion and two phase related problems 544 00:13:03,860 --> 00:13:03,870 diffusion and two phase related problems 545 00:13:03,870 --> 00:13:07,490 diffusion and two phase related problems such as crystal growth he will also 546 00:13:07,490 --> 00:13:07,500 such as crystal growth he will also 547 00:13:07,500 --> 00:13:09,140 such as crystal growth he will also explore the potential of thermo 548 00:13:09,140 --> 00:13:09,150 explore the potential of thermo 549 00:13:09,150 --> 00:13:11,330 explore the potential of thermo capillary convection for the droplet 550 00:13:11,330 --> 00:13:11,340 capillary convection for the droplet 551 00:13:11,340 --> 00:13:13,610 capillary convection for the droplet radiators involved in the Space 552 00:13:13,610 --> 00:13:13,620 radiators involved in the Space 553 00:13:13,620 --> 00:13:16,960 radiators involved in the Space Station's power system such 554 00:13:16,960 --> 00:13:16,970 Station's power system such 555 00:13:16,970 --> 00:13:19,400 Station's power system such computational studies are laying the 556 00:13:19,400 --> 00:13:19,410 computational studies are laying the 557 00:13:19,410 --> 00:13:21,740 computational studies are laying the groundwork that will enable NASA 558 00:13:21,740 --> 00:13:21,750 groundwork that will enable NASA 559 00:13:21,750 --> 00:13:24,070 groundwork that will enable NASA and its partners in academia and 560 00:13:24,070 --> 00:13:24,080 and its partners in academia and 561 00:13:24,080 --> 00:13:27,140 and its partners in academia and industry to design the expensive 562 00:13:27,140 --> 00:13:27,150 industry to design the expensive 563 00:13:27,150 --> 00:13:30,080 industry to design the expensive experimental ventures in outer space of 564 00:13:30,080 --> 00:13:30,090 experimental ventures in outer space of 565 00:13:30,090 --> 00:13:34,340 experimental ventures in outer space of the coming decade together numerical and 566 00:13:34,340 --> 00:13:34,350 the coming decade together numerical and 567 00:13:34,350 --> 00:13:36,740 the coming decade together numerical and experimental studies we'll be able to 568 00:13:36,740 --> 00:13:36,750 experimental studies we'll be able to 569 00:13:36,750 --> 00:13:38,900 experimental studies we'll be able to meet the challenge of exploiting the 570 00:13:38,900 --> 00:13:38,910 meet the challenge of exploiting the 571 00:13:38,910 --> 00:13:41,270 meet the challenge of exploiting the revolutionary capabilities the space 572 00:13:41,270 --> 00:13:41,280 revolutionary capabilities the space 573 00:13:41,280 --> 00:13:43,790 revolutionary capabilities the space station offers thus helping to fulfill 574 00:13:43,790 --> 00:13:43,800 station offers thus helping to fulfill 575 00:13:43,800 --> 00:13:46,550 station offers thus helping to fulfill the Space Station's promise as the 576 00:13:46,550 --> 00:13:46,560 the Space Station's promise as the 577 00:13:46,560 --> 00:13:50,150 the Space Station's promise as the laboratory of the future