航空发动机金属海绵通风器分离特性数值研究

Separation characteristic Numerical Simulation of Air-oil Separator with Metal Foam in Aero-engine

建立了一套金属海绵分离特性的数值研究方法。以金属海绵和金属海绵通风器为研究对象,采用体心立方模型作为金属海绵的简化模型;采用N-S方程求解流场,运用DPM模型对研究对象的油气分离特性进行了数值计算;并通过实验数据验证了该方法的有效性和可靠性。在此基础上,分析了不同的金属海绵结构参数、不同的通风器工况对分离特性的影响。结果表明,金属海绵有较大的孔密度和较小的孔隙率时,对油滴的分离效率更高;而金属海绵通风器的转速和入口流量较大时,对油滴的分离效率更高。研究发现,金属海绵通风器对尺寸很小的油滴有很好的分离效率并具有更好的综合性能。

A numerical method for the separator s filtration of metal foam was established.Metal foam and separator of metal foam are studied.The body-centred cubic model was used to simplify the structure of metal foam,the N-S equations were applied to solve the flow field,and oil and gas separation characteristic was computed by DPM model.The computational method was validated by experimental data from literature.On this basis,the influence of different metal foam structural parameters and different air-oil separator working conditions on the separation characteristics was analyzed.The results show that metal foam with higher the pores per inch(PPI)and lower porosity has better performance of filtration.It is also found that when the separator rotates faster or works with higher flow rate,the separator performs better in filtering oil drops.Separator s filtration of metal foam have good separation efficiency for small size oil droplets and have better overall performance.