Oblique jet wall impingement has a wide range of applications in multiple fields such as liquid film cooling of liquid rocket engines and atomization. To study the key characteristics of the liquid film formed by the oblique jet wall impingement, we conducted an experimental study on a single cylindrical jet impinging onto the wall. The effects of various jet parameters on the liquid film shape were studied in the experiments, and theoretical modeling research was carried out to obtain the key geometric parameter expressions of the liquid film shape. It is found that as the jet angle increases, the liquid film length decreases and the width increases. As the jet diameter and velocity increase respectively, the liquid film length and width increase. Through theoretical analysis, the angle between the maximum width position and the symmetry plane of the liquid film is approximately equal to the incident angle α, and the aspect ratio of the liquid film 1+cot α. Further analyses obtain the geometric parameter expressions of the liquid film shape such as the width, the length, and the distance between the maximum width and the impinging point. The errors between the prediction and the experimental results are within 20% in the geometric parameter expressions established above.
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