菱形孔射流在超声速流场中的气动特性

针对带有横向射流的三维超声速流场进行数值模拟,分析了菱形结构喷孔与普通圆孔的差异,并探讨了不同喷射角度下菱形喷孔对流场的影响.研究结果表明：与普通圆孔相比,采用菱形孔射流能够减弱弓形激波的强度、降低总压损失,增加燃料的穿透高度,但是在展向方面两者对于燃料的扩散能力基本相同;随着喷射角度的增加,燃料的穿透高度表现出先增加后降低的趋势,在计算的3种模型中,喷射角为60°表现出更好的特性;喷射角度在一定范围内变化时,总压损失的改变不明显,但是过大的喷射角度会导致总压损失迅速增加.通过研究进一步认识了菱形孔射流的流场特性,为优化喷射装置提供依据.

Aerodynamic characteristics of sonic injection through diamond-shaped orifices in supersonic flow field

Three-dimensional supersonic flow field with sonic injector was numerically investigated,the characteristics of diamond-shaped orifice which were compared with that of the circular injector were analyzed,and at last the effect of the diamond-shaped orifice on the flow field with different injection angles was explored.It is found that the plume from diamond-shaped orifice can weaken the strength of the bow shock and reduce total pressure loss,and the fuel penetration height of diamond-shaped orifice is higher than that of the circular injector,however,the diffusivity is almost the same in spanwise direction regardless of the structure type of injector.With the increase of the injection angle,the penetration height of the fuel firstly increases and then decreases;the model with 60 degree injection angle has the best characteristics.The change of total pressure loss is not obvious when the injection angle changes within a certain range,whereas an injection angle which is too large would lead to a rapid increase in the total pressure loss.This investigation provides insight into the characteristics of flow field with diamond-shaped orifice,which is crucial for optimization of injector.