扩口孔型预旋喷嘴流动与温降特性

Investigation on Flow Characteristics and Temperature Drop of an Aerodynamic-Hole Typed Pre-Swirl Nozzle

关键词:  预旋系统  预旋喷嘴  温降  流量系数  预旋效率 

Key words:  Pre-swirl system  Pre-swirl nozzle  Temperature drop  Discharge coefficient  Pre-swirl effectiveness

摘要:

分别对预旋角度为20°的直孔和扩口孔型喷嘴进行了数值模拟和实验测量。计算模型包括仅有进气腔、预旋孔和出气腔的单独模型和在此基础上增加了旋转部分的系统模型；研究内容包括速度场、出气速度、出气角度、流量系数、预旋效率和温降,并对单独模型的孔流量系数进行了实验测量。结果表明流量系数的计算结果与实验结果符合良好,扩口孔的流量系数、预旋效率和温降都比直孔显著增大20%以上。数据还显示由单独模型计算得到的流量系数和预旋效率与由系统模型得到的结果比较接近,根据单独模型的预旋效率而推算出的温降可在一定程度上间接反映预旋系统的温降特性。 

Abstract:

Both simple drilled hole and the aerodynamic hole with pre-swirl angle of 20° were numerically simulated and measured. The computational models include standalone model which contains only the inlet chamber, pre-swirl hole and exit chamber, and system model which contains rotating parts on the basis of standalone model. The investigated parameters are velocity contour, outlet velocity, velocity angle, discharge coefficient and pre-swirl effectiveness,repectively. The discharge coefficient of standalone model was measured. Results show that the measured and calculated discharge coefficient coincide well, and the discharge coefficient, pre-swirl effectiveness and temperature drop of the aerodynamic hole are increased by more than 20%, compared with that of the simple drilled hole. Data also reveal that the discharge coefficient and pre-swirl effectiveness obtained from the standalone model are close to that from the system model, and the temperature drop predicted via the pre-swirl effectiveness of standalone model can reveal the temperature drop characteristics of pre-swirl system indirectly. 