空气系统径向内流引气的流动特性数值分析

Numerical Simulation of Radial Inflow in Air System

关键词:  空气系统  径向内流  导流盘  旋流系数  科氏力  数值模拟 

Key words:  Air system  Radial inflow  Guide disk  Swirl ratio  Coriolis force  Numerical simulation

摘要:

对有/无导流盘引气结构的空气系统径向内流引气进行数值模拟,并对两者的流场和气流沿程总温进行对比分析。研究表明导流盘能显著降低气流的沿程总温,总温降高达40K,而无导流盘引气结构的总温降仅为10K。导流盘能减少气流的流动阻力,在小流量情况下的减阻作用更为明显。两种引气结构的旋流系数峰值随引气流量的增加而增大。在大引气流量下,带导流盘引气结构的旋流系数峰值高达3.0,其减阻优势严重削弱。通过对外作功和降低气流的旋转速度,导流盘具有减阻降温的作用,可以显著地提高空气系统的引气品质。 

Abstract:

In order to reveal the flow characteristic of radial inflow of air system, the numerical simulation of flow at bleeding structures with/without guide disk was performed.The comparison of the flow field and the total temperature along flow path between two bleeding structures was carried out as well. The results indicate that the lower flow resistance, especially for flow at low mass flow rate, and the higher total temperature decrease of airflow is achieved by using the guide disk. The decrease of total temperature for bleeding structure with guide disk is reached 40K while another structure gains 10K total temperature reduction. The peak value of swirl ratio grows up with the increase of mass flow rate at two bleeding structures. The peak value at the structure using the guide disk is achieved 3.0in large mass flow rate, which weakens the function of reducing flow resistance. The performance of the bleeding air in terms of resistance decrease and total temperature decrease is obviously improved through transferring power outwards and decreasing the swirl velocity of air flow by the guide disk. 