Abstract: To investigate the falling film evaporation process of R134 a（C₂H₂F₄） on horizontal tube, the volume of fluid（VOF） model and the user-defined functions（UDF） were used to numerically simulate the flow and heat transfer characteristics of the liquid film on tubes, including the flow of liquid film along the axial direction and circumferential direction of cross section of heat exchange tubes（corrugated tubes and smooth tubes）, the thickness and distribution of liquid film and the bubbles nucleation and distribution in liquid film. The calculation results show that when the heat flux on the wall is 2×10~4 W·m^-2, both flow and heat transfer of the R134 a liquid film have differences between corrugated tube and smooth tube in the axial and circumferential direction. Along the axial direction, the spreading speed of the liquid film on corrugated tube is 2.0 ms faster than that on smooth tube, while along the circumferential direction, the liquid film spreads more uniformly and slowly than that on smooth tube. The average thickness of the liquid film on corrugated tube is 0.120 mm, which is 7.00% thinner than that on smooth tube. The thickness of liquid film on the front area of tube is 0.119 mm, which is 13.14% thinner than that on smooth tube. Compared with smooth tube, the first bubble nucleation in the liquid film on corrugated tube occurs 2.6 ms earlier, and the number of bubble nucleation is 15.32% more than that on smooth tube, while the range of bubble nucleation is larger with more bubble nucleation occurring at circumferential angles of 55°-135°. The average heat transfer coefficient on corrugated tube is 10.17% higher than that on smooth tube, and the heat transfer coefficient on the front area is 3.53 times bigger than that on the back area.