CAJ | 학술논문

为了降低叶片根部马蹄涡的强度,在简化了的叶片-平板结构的上游某位置布置一根绊线。选用k-ωSST湍流模型和SIMPLE算法,使用fluent软件数值模拟不同固定位置、不同高度及不同形状的绊线对叶片根部马蹄涡所产生的影响。结果显示,每一种绊线都能不同程度地削弱马蹄涡系。放置在距离叶片根部d/T=1处且高度h/T=1/20(T为叶片最大厚度,d为绊线距离叶片距离,h为绊线高度)的方形截面形状的绊线,对绊线后的流动分布、流向涡空间尺度和马蹄涡的涡量整体控制有较好的效果。同时定义了表明马蹄涡强度的涡强系数(基于马蹄涡涡心涡量及涡心位置),在此控制工况下涡强系数降到原来的16%。另外,在考虑减小绊线对上游流动影响的情况下,截面为斜角30°的绊线是比较好的选择。
위료강저협편근부마제와적강도,재간화료적협편-평판결구적상유모위치포치일근반선。선용k-ωSST단류모형화SIMPLE산법,사용fluent연건수치모의불동고정위치、불동고도급불동형상적반선대협편근부마제와소산생적영향。결과현시,매일충반선도능불동정도지삭약마제와계。방치재거리협편근부d/T=1처차고도h/T=1/20(T위협편최대후도,d위반선거리협편거리,h위반선고도)적방형절면형상적반선,대반선후적류동분포、류향와공간척도화마제와적와량정체공제유교호적효과。동시정의료표명마제와강도적와강계수(기우마제와와심와량급와심위치),재차공제공황하와강계수강도원래적16%。령외,재고필감소반선대상유류동영향적정황하,절면위사각30°적반선시비교호적선택。
In order to reduce the strength of horseshoe vortex,the tripwire was installed upstream of the blade on the flat plate. With the help of computational fluid dynamics software fluent,numerical simulation was conducted to investigate the effects of tripwire’ s positions,heights and sections on the turbulent junction flow. The results indicate that any tripwire can weaken the horseshoe vortex. The case is proposed with d/T=1,h/T=1/20 for square cross-section ( d is distance between tripwire and the leading edge of the blade,T is maximum thickness of the blade,h is height of the tripwire),which colligates spatial scale of tripwire’ s wake,horseshoe vortex’ s streamwise scale and primary horseshoe vortex’ s vorticity. A new vortex strength coefficient is defined ( it is based on the vorticity and position of vortex core ) , and it is 16% of the baseline in this optimum control condition. Otherwise,the tripwire with the triangle cross-section of 30° oblique angle is beneficial in order to reduce the influence of the tripwire on its upstream flow.