CuO纳米流体作为柴油机冷却介质的数值计算分析

Numerical Simulation on CuO Nanofluids as Cooling Mediumin Diesel Engine Cooling System

用CuO纳米流体作为柴油机的冷却介质,运用计算流体力学(CFD)方法对CuO粒子质量分数为1%,3%和5%的CuO纳米流体在柴油机冷却水套内的流动和换热过程进行三维数值模拟,并采用湍流随机跟踪方法,对固液两相流离散项纳米粒子的运动进行轨迹追踪,得到了不同CuO质量分数的纳米流体在柴油机水套内的CuO粒子分布,速度场分布,换热总量以及水套进出、口之间的压降变化。计算结果表明,CuO纳米流体作为介质可以显著提高柴油机的散热性能,随着纳米粒子的增加,柴油机散热能力增强,水泵功率损失小范围增加。

CuO nanofluids was utilized as cooling medium in the diesel engine cooling system.By using CFD method,for 1%,3% and 5% mass concentration of nanofluids,3-dimensional numerical simulation about flow and heat transfer process in the cooling system of engine was actualized.According to stochastic particle tracking in turbulent flow,in solid-liquid two phase flow discrete phase,the moving track of nanoparticles was traced.By this way,the concentration distribution,velocity distribution,total heat transfer quantity and variation quantity of total pressure reduction between inlet and outlet were ascertained in CuO nanoparticles for different mass concentration nanofliuds in the cooling jacket of diesel engine.It is proved by simulation results that nanofluids as cooling medium can evidently enhance diesel engine heat transfer capability.When the concentration of nanoparticles increases,the enhancement of heat transfer capacity increases and power loss of water pump also increases in a limited operation range.