Research on convective heat transfer coefficient with air jet impinging

With the airflow temperature 105～135℃,airflow rate 6.7～14.4m/s and relative humidity 0～30%.Research on convective heat transfer coefficient h in the air imping ment oven, the result indicates that when the temperature T is close to the saturation temperatures of gas(T_s), convective heat transfer coefficient h have changed,h_TT>Ts; When the temperature T< T_s, convective heat transfer coefficient h becomes greater while the humidity or the airflow rate is greater. The greatest hcan get to 1403w/(m²K); When the temperature T>T_s, the value of hbecomes smaller than ever, agreed on the value at humidity 0%.With the variety of temperature & humidity, the changes of his not significant at the constant airflow rate. At the constant temperature, the value of h increased with increased airflow rate, and the changes of his no obvious with increased humidity. The value of h ranged from 120 to 136 w/(m²K).