电动燃油泵轴向油冷壳体隔板的数值研究

Numerical study on partition of axial fuel-cooling case on electric fuel pump

针对电动泵油冷散热效果与可靠性问题,对电动燃油泵轴向油冷壳体结构从温升、冷却油温度分布均匀度和流道压力降等方面进行了分析,基于流固耦合数值模拟研究了油冷壳体隔板数量和布置方式的设计方法,提出了一种变距隔板冷却结构,并将其与等距壳体进行了对比,研究了8-32范围内隔板数对流速、雷诺数、流道压降及温度场分布的影响规律,并研究了电动燃油泵电机功率对内壁面温度和冷却燃油压降的影响。研究结果表明:对额定功率8 k W、热损耗10%的电动泵,隔板数为18时冷却效果达到饱和,继续增加隔板数难以显著提升冷却效果,且燃油流经冷却壳体的压降显著增加,但温度分布更加均匀。

Aiming at fuel cooling effects and reliability of electric fuel pumps,axial fuel cooling case structure for the pump was analyzed from aspects of temperature rise,evenness degree of fuel temperature and pressure drop along the cooling flow path. Fluid solid coupling numerical simulation was carried out for designing the number and layout of the axial partitions in the cooling case. A kind of varying-distance cooling case was proposed and compared with the equidistant case. Influences of partition number from 8 to 32 on velocity,Reynolds number,pressure drop and temperature field distribution of fuel in the case were investigated,using equidistant and varying-distance cooling cases respectively. The results indicate that 18-partition cooling case creates heat emission saturation with regards to the pump of 8 k W rated power and 10% thermal loss. More than 18 partitions cannot lead to remarkable improvement on heat emission capacity but increasing pressure drop across the case and more even temperature distribution on the wall.