摘要
采用RNGk-ε湍流模型对射流出射角度α为90o、正、负60o和正、负30o的气膜冷却流场进行了数值模拟,结合SIMPLEC算法求解了适体坐标系下的控制方程,近壁区流动采用两层模型的壁面函数法处理,结果给出了射流与主气流速度比R为2和4时的射流轨迹和速度场。结果表明:R和α值是影响气膜冷却流场的重要因素,R值增加,冷气射流对主流场影响区域增加,α值为负时,射流对主流场上游影响区域较大,当α值为30o时,射流影响区域减小;当α为正值时,随α值的减小,射流喷孔下游背风侧的分离现象逐渐消失。
By using the RNG κ-ε turbulence model numerical simulations were performed to investigate the characteristics of the film cooling flows, at the jet injection angles of 90, ±60 and ±30 deg. The SIMPLEC algorithm in the body-fitted coordinates and the modified wall function method, two-layer model, was adopted to simulate the flow in the near-wall region and the outer core flow, at two jet-to-crossflow velocity ratios, 2 and 4. The jet trajectories and the velocity fields were given. The results show that a jet with negative injection angles affects the most main flow range and the affected range is least at the injection angle of 30 deg. There are separate events in the lee of the jet, but these events are not obvious at the positive-angled injection,
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第16期117-121,共5页
Proceedings of the CSEE
基金
国家自然科学基金项目(50476037)~~
关键词
热能动力工程
气膜冷却
紊动射流
湍流模型
数值模拟
thermal power engineering
film cooling：turbulent jet
turbulence model： numerical simulation
