CAJ | 학술논문

采用数值模拟方法对导叶轮缘放气、进气回流及周向槽机匣处理扩大离心压气机稳定工作范围进行研究,并与实壁机匣离心压气机特性进行对比,分析三种处理方式扩大压气机稳定工作范围的机理.结果表明,导叶顶部吸力面分离流动和间隙泄漏流相互作用导致压气机失速.导叶轮缘放气将吸力面分离流动产生的低能流团吸除,减弱了项部通道堵塞.进气回流给顶部进气添加负预旋,减小了顶部来流攻角,能抑制吸力面流动分离.周向槽机匣处理减弱了项部间隙泄漏向叶轮进口的回流.三种处理方式都能减弱顶部通道堵塞、推迟压气机失速发生,而进气回流和导叶轮缘放气具有较大的扩稳能力.
채용수치모의방법대도협륜연방기、진기회류급주향조궤갑처리확대리심압기궤은정공작범위진행연구,병여실벽궤갑리심압기궤특성진행대비,분석삼충처리방식확대압기궤은정공작범위적궤리.결과표명,도협정부흡력면분리류동화간극설루류상호작용도치압기궤실속.도협륜연방기장흡력면분리류동산생적저능류단흡제,감약료항부통도도새.진기회류급정부진기첨가부예선,감소료정부래류공각,능억제흡력면류동분리.주향조궤갑처리감약료항부간극설루향협륜진구적회류.삼충처리방식도능감약정부통도도새、추지압기궤실속발생,이진기회류화도협륜연방기구유교대적확은능력.
To enhance the stall margin, the performance of a centrifugal compressor with inducer bleeding, inlet recirculation and circumferential grooves casing treatment respectively is numerically simulated by using CFD software. The difference of the performance between solid casing and stall improvement techniques casing compressor are compared. The mechanisms of improved stability of the applied techniques are investigated. The results indicate that the interaction of tip-leakage and the separation flow at the leading edge of the inducer suction side leads to the compressor stall. With inducer bleeding, the low energy fluid formed in the flow separation flows out of the main flow channel. With inlet recirculation, the fluid from the recirculation channel adds negative pre-swirl to the inlet flow, which reduces the inlet tip incidence and restrains the flow separation on the suction side. Circumferential grooves casing treatment reduces the reverse flow of the tip-leakage to the impeller inlet. All the applied techniques can decrease the flow blockage near the inducer tip and delay the occurrence of stall, but inducer bleeding and inlet recirculation are more effective.