Abstract: In this paper,the hot air swept solar distiller is taken as the research object. Based on the numerical simulation results and uniform design method,this paper analyzes the variation law and influencing factors of the synergistic Angle between flow and heat transfer field in a solar distiller with hot air blowing. The result shows that the main factor affecting the field synergy Angle is the hot air inlet velocity,the influence of hot air inlet temperature and water temperature is not significant. When the distilled water temperature is30-70 ℃ and the inlet air temperature is 40-90 ℃,the average heat transfer field synergy Angle is the minimum（73.14°）when the inlet air speed is 8 m/s. At this time,the heat transfer coefficient is the maximum,which can reach 4 times of the natural convection heat transfer coefficient under the same conditions.