Multi-walled carbon nanotube(MWCNT)nanoparticles were added into distilled water with hydrophilic TNWDIS of nonionic-type as surfactant. In order to get the stable homogeneous dispersions of MWCNT-H2O nanofluid,ultrasonic generator was used. Under the condition of 100Pa and adsorption,the effects of nanofluid for different mass fractions,particle sizes of MWCNT and different ratios between MWCNT&TNWDIS on static vacuum flash characteristics of ice-making were studied. The results showed that the addition of MWCNT can eliminate the stage of phase-change and shorten the cooling time at the stage of liquid phase. So the supercooling phenomenon appeared earlier. The 20—40nm MWCNT-H2O nanofluid which the concentration ranges from 0.075% to 0.15% can be well-distributed by TNWDIS. When the concentration of MWCNT was 0.1%,the supercooling degree of water decreased by 62.2%,which reached the maximum reduction. The supercooling degree increased with the increase of particle size,while the flash evaporating rate remained at 40%. However,ice packing factor is varied nonlinearly. The optimal dispersive proportion of TNWDIS and 20—40nm MWCNT is 0.5:1. Under this dispersive proportion,the supercooling degree of 0.1% MWCNT-H2O nanofluids remained at 2℃.%在蒸馏水中加入多壁碳纳米管(MWCNT)纳米粒子,选用亲水性非离子型表面活性剂 TNWDIS 为分散剂.经过超声波震荡,配制分散均匀稳定的MWCNT-H2O纳米流体.利用静态真空闪蒸实验台,设定系统压力为100Pa,研究在吸附作用下多壁碳纳米管纳米粒子浓度、粒径、TNWDIS与MWCNT配比对闪蒸制取冰浆实验的影响.结果表明,多壁碳纳米管的加入可消除闪蒸制冰的相变蓄冷阶段、缩短液相降温时间使流体更早出现过冷现象;20～40nm粒径的MWCNT纳米粒子使用TNWDIS进行分散,质量分数范围在0.075%～0.15%时多壁碳纳米管纳米流体分散均匀稳定、达到最佳效果,其中质量分数为 0.1%的纳米流体最大降低水的过冷度达62.2%;过冷度随着MWCNT纳米粒子粒径的增大而升高,闪蒸率基本维持在40%,但含冰率呈现非线性变化;20～40nm粒径的 MWCNT纳米粒子使用TNWDIS配制成质量分数为 0.1%的纳米流体,TNWDIS与MWCNT的分散配比建议采用0.5:1,过冷度基本维持在2℃.
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