高级检索+

多翼离心风机双圆弧叶片设计及其性能优势分析

Design of double-arc blades for multi-blade centrifugal fan and analysis of its performance advantages

  • 摘要: 在限定直径下对某吸油烟机用多翼离心风机的单圆弧叶片进行双圆弧改型,研究了加、减速2种双圆弧叶型对风机性能的影响,并对单双圆弧叶型各自的性能优势展开对比分析.通过计算流体力学数值预测不同叶型方案的整机风压及效率,确定单圆弧叶片进口安装角的最佳取值区间应在最小冲击损失设计的基础上预设20.0°~30.0°冲角,而综合风机压力和效率,单圆弧叶片出口安装角的最佳取值为165.0°~173.0°.对于进口安装角匹配不佳的单圆弧叶片,采用减速型双圆弧叶片可同时提高风机压力和效率;但对于已经优选过的单圆弧叶型,则反而需向加速型双圆弧改型,风机压力小幅度提高但效率稍有降低.对比同叶片进出口角的单圆弧叶片,加速型双圆弧叶片做功重心前移的同时,吸力面二次分离得到抑制;其叶道更难被蜗舌回流贯穿,有利于风机小流量工况下的气动性能.

     

    Abstract: The single-arc blades of a multi-blade centrifugal fan used in a range hood was modified to double-arc designs within a diameter limitation. The effects of acceleration and deceleration double-arc blades on fan performance were studied, and the performance advantages of both single and double-arc blades were compared and analyzed. The fan pressure and efficiency of different blade schemes were numerically predicted through computational fluid dynamics. The optimal value range of the inlet angle of the single-arc blade should be preset based on the minimum-impact-loss design with an attack angle of 20.0°-30.0°. Considering comprehensively the fan pressure and efficiency, the optimal value of the outlet angle of the single-arc blade is between 165.0° and 173.0°. For single-arc blades with poorly matched inlet angle, the use of deceleration double-arc blades can increase the fan pressure and efficiency. However, for the single-arc blades that are already optimized, only retrofitting to the acceleration type could further increase the fan pressure, but the efficiency will slightly decrease. Compared with the single-arc blades with the same blade angles, the working load of the acceleration double-arc blades moves upstream, and the secondary separations on the blade suction surface are also inhibited. The blade passages are more difficult to be penetrated by the volute tongue reverse flow, which benefit the fan aerodynamic performance under low-flow conditions.

     

/

返回文章
返回