the heat transfer and pressure drop characteristics of the tube fin with interrupted half annular grooves were investigated under different fin spaces. The air side heat transfer and pressure drop correlations with Re number for each fin spaces were obtained.As compared with the smooth tube fin heat exchanger surface
both the heat transfer and pressure drop coefficients of the heat exchanger surface increase greatly and the pressure drop increased even more. The experiment results obtained can be used as the basis for adopting or designing new tube fin heat exchangers.