Experimental and Numerical Study of Twin Underexpanded Impinging Jets

作     者：Minoru Yaga Minoru Okano Masumi Tamashiro Kenyu Oyakawa 

作者机构：Department of Mechanical Systems Engineering Faculty of Engineering University of the RyukyusSenbaru 1 Okinawa 903-0213 JAPANDepartment of Mechanical Systems Engineering Faculty of Engineering University of the RyukyusSenbaru 1 Okinawa 903-0213 JAPANDepartment of Mechanical Systems Engineering Faculty of Engineering University of the RyukyusSenbaru 1 Okinawa 903-0213 JAPANDepartment of Mechanical Systems Engineering Faculty of Engineering University of the RyukyusSenbaru 1 Okinawa 903-0213 JAPAN 

出 版 物：《Journal of Thermal Science》 (热科学学报（英文版）)

年 卷 期：2003年第12卷第3期

页      面：255-259页

核心收录：

学科分类：080704[工学-流体机械及工程] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：Takahasi Industry Economy Research Foundation 

主　　题：可压缩流体力学 冲击波 碰撞射流 CFD 计算流体力学 喷射流动 实验研究 数值分析 

摘      要：In this paper, the dual underexpanded impinging jets are experimentally and numerically studied. The experiments were performed by measuring the unsteady and averaged wall static pressures and by visnalizing density fields using schlieren method. Numerical calculations were also conducted by solving unsteady three dimensional compressible Navier-Stokes equations with Baldwin-Lomax turbulence model. The main parametm s for the dual jets are the non-dimensional distance between the two nozzle centers H/D covering 1.5, 2.0, the nozzle to plate separation L/D 2.0, 3.0,4.0 and 5.0 and the pressure ratio defined by Po/Pb 1.0-6.0, where D is the diameter of each nozzle exit, Po the stagnation pressure and Pb the back pressure. It is found that the agreement between the experiments and the calculations is good. The fountain flow at the middle of the two jets is observed both in the experiments and the calculation. According to FFT analysis of the experiments for the twin jets,relatively low frequgncy (up to 5 kHz) is dominant for H/D =1.5, L/D =2.0 and pressure rafio po/Pb =3.0 and 5.0,which is confLrmed by the experiments.