纳米铝粉粒径对丁醇柴油基纳米流体燃料液滴蒸发特性的影响

Effect of nano aluminum powder particle size on the evaporationcharacteristics of aluminum/butanol diesel-based nanofluid fuel droplets

通过丁醇柴油添加纳米铝颗粒,利用挂滴式实验装置研究纳米流体单液滴的蒸发特性.在蒸发炉内,比较含不同粒径为50、80、150 nm的纳米流体,环境温度分别为623、923 K.单液滴在923 K下的蒸发阶段可分为瞬态加热阶段、波动蒸发阶段和平衡蒸发阶段.而在623 K仅有瞬态加热阶段和平衡蒸发阶段;当环境温度为623 K时,液滴蒸发寿命随着纳米粒子的粒径增大而增大,且纳米粒子的加入抑制液滴的蒸发;环境温度为923 K下,粒子粒径为50 nm的纳米流体蒸发寿命最短.可见在高温下纳米粒子将促进液滴的蒸发,并且相对较小粒径的纳米粒子的促进作用更明显.

Nano-aluminum particles were added through butanol diesel fuel,and the evaporation characteristics of nanofluid single droplets were studied using a hanging drop experimental device.In the evaporation furnace,nanofluids with different particle sizes(50 nm,80 nm,150 nm)are compared for the ambient temperatures of 623 K and 923 K,respectively.The evaporation stage of a single drop at 923 K can be divided into transient heating stage,fluctuating evaporation stage and equilibrium evaporation stage.At 623 K,there are only transient heating phase and equilibrium evaporation phase.When the ambient temperature is 623 K,the evaporation life of the droplets increases as the particle size of the nanoparticles increases,and the addition of the nanoparticles inhibits the evaporation of the droplets.At an ambient temperature of 923 K,the nanofluid with a particle size of 50 nm has the shortest evaporation life.It can be seen that nanoparticles will promote the evaporation of droplets at high temperatures,and the promotion effect of nanoparticles with relatively small diameters is more obvious.