Effect of jet diameter on the maximum surface heat flux during quenching of hot surface

A stainless steel surface of 0.25 mm thickness at 800 ± 10 °C initial temperature was quenched by the jet impingement cooling method. The transient surface heat flux was determined during surface quenching with three different jet diameter The flow of water at 22 ± 1 °C temperature was regulated to maintain the jet Reynolds number in a range of 5000–24 000. The observations were made form the stagnation point to the 12 mm downstream spatial location. The quenching performance of the horizontal test surface was evaluated on the basis of maximum surface heat flux obtained during transient cooling. observed that the maximum surface heat flux increases with the rise in jet diameter and became the highest for the largest jet diameter at Re = 24 000. The correlations developed to determine the maximum surface heat flux was able to predict the experimental data well within the error band of ±15%.