基于VOF方法的汽车油箱燃油晃动数值模拟分析

Numerical Simulation of Fuel Sloshing in Automobile Fuel Tank Based on VOF Method

目的研究燃油在汽车油箱中的晃动规律,为汽车油箱的结构可靠性设计和汽车燃油的稳定供给提供参考和依据。方法建立某款汽车油箱的几何模型,利用VOF(volume of fluid)方法进行数值模拟。采用控制变量法,对比分析有无隔板、不同冲击加速度、不同充液比对燃油晃动及油箱壁面所受压力的影响。结果无隔板、较大冲击加速度的情况下,燃油晃动更为剧烈,吸油管出现瞬间吸空现象,导致燃油供给不稳定,油箱受到的压力更大,影响油箱的结构可靠性。较小充液比的情况下,由于燃油晃动,吸油管容易出现瞬间吸空现象,导致燃油供给困难。结论汽车油箱采用隔板、保持较小的冲击加速度和较大充液比有利于防止吸油管瞬间吸空,从而保证燃油的稳定供给。充液比太大会造成油箱壁面所受压力增大,因此,应该保持合理的充液比。

Objective To study the sloshing law of fuel in automobile fuel tank and provides reference and basis for structural reliability design of automobile fuel tank and stable supply of automobile fuel.Methods The geometric model of a certain type of automobile fuel tank was established.The VOF(volume of fluid)method was used for numerical simulation.The control variable method was used to compare and analyze the effects of different baffles,different impact acceleration and different filling ratio on the fuel sloshing and the pressure on the wall of the fuel tank.Results In the case of no baffle and large impact acceleration,the fuel sloshing was more intense,the suction pipe had instantaneous suction phenomenon,which lead to the instability of fuel supply and the greater pressure on the fuel tank,affecting the structural reliability of the fuel tank.In the case of small filling ratio,because of the fuel sloshing,the suction pipe was prone to instantaneous suction,which lead to the difficulty of fuel supply.Conclusion The use of partition,small shock acceleration and large filling ratio in the automobile fuel tank are beneficial to prevent the suction pipe from being sucked out instantaneously,thus ensuring the stable supply of fuel.However,the pressure on the tank wall will increase if the filling ratio is too large.Therefore,a reasonable filling ratio should be maintained.