Experimental and Numerical Analysis of Pressure Gain and Velocity Profile by Inclined Jet Injection in Duct Flow

为了了解斜喷流进入矩形截面隧道风管的流场和压力增益特性，我们进行了1/30比例的模型实验。针对不同导叶形状下射流的压力特性和速度分布，进行了一系列的实验。重点介绍了“平型”叶片的试验情况，认为这在实际应用中具有重要意义。对于30度接近的射流，最有利的导叶类型是长度与射流宽度相等且平行长度相同的平板导叶。此外，利用商业代码对该模型进行了数值模拟。数值结果与实验结果吻合较好。从压力增益和隧道安全的角度出发，找到了最有利的喷嘴形状。

In order to know the flow field and pressure gain characteristics with an inclined jet injection into a tunnel duct with rectangular cross section, we have performed a model experiment with a 1/30 scale. A series of experiment gave results on the flow field by the jet, in view of pressure characteristics and velocity profile, depending on the shape of guide vanes. Stress was laid on the experimental cases for the "flat type" vanes, which is considered to be important from practical aspects. The most favorable guide vane type for a 30 degree approaching jet was the one with the flat plate with the length equal to the jet width, and same parallel length. In addition numerical simulation for the model was carried out using a commercial code. Numerical results showed good agreement with the experimental results. As conclusion, we have found the most favorable shape of jet injection nozzle in view of pressure gain and tunnel safety.