Sensitivity study of geometry parameters of the combustor dump diffuser

燃烧室突扩扩压器的几何参数敏感性研究

School of Power and Energy, Northwestern Polytechnical University, Xi'an 710129, China

Received: 28 December 2023

Abstract

Experimental and numerical simulation studies were carried out to investigate the effects of different structural parameters on the performance and flow characteristics of the combustion chamber dump diffuser. The results show that different single structural parameters have different influences on the performance and flow field. When the expansion angle of the pre-diffuser is increased from 1.2° to 18°, the total pressure loss coefficient of the diffuser is reduced by 35.71%, 34.97% and 37.26% in the three working conditions, respectively. When the inclined angle of the pre-diffuser is increased from 0° to 30°, the total pressure loss coefficient of the diffuser increases by 48.57%, 50.79% and 49.43% in the three working conditions, respectively. When the relative dump gap ratio changes from 1 to 3, the total pressure loss of the diffuser first decreases and then increases. The expansion angle of the pre-diffuser has a major influence on the performance of the dump diffuser under different operating conditions, and the coupling between the expansion angle of the pre-diffuser and the inclined angle of the pre-diffuser has a major influence on the diffuser.

摘要

针对燃烧室突扩扩压器的性能和流动特性开展试验和数值模拟研究, 探究不同结构参数对燃烧室突扩扩压器的影响。结果表明: 不同单一结构参数对性能和流场的影响规律不同, 当前置扩压器扩张角从1.2°增大到18°时, 扩压器的总压损失系数在3个工况下分别降低了35.71%, 34.97%和37.26%。当前置扩压器倾斜角从0°增大到30°时, 扩压器的总压损失系数在3个工况下分别增大了48.57%, 50.79%和49.43%。当相对突扩间隙比从1变化到3时, 扩压器的总压损失先减小后增大; 不同工况下前置扩压器扩张角对突扩扩压器的性能影响都较大, 二阶项前置扩压器扩张角和前置扩压器倾斜角之间的耦合作用对扩压器影响较大。