Convection overview Consider a flat plate of length L,in air flow with velocity u and temperature To yA 1 1 Local heat flux is: where h is the local heat transfer coefficient q"=h(T,-T) Total heat transfer rate: 9=∫9d4,=(T,-T) hdA. q=hA,(Ts-T) 万= average heat transfer coefficient Determination of h'will rely on analytical as well as empirical data Heat Transfer Su Yongkang School of Mechanical Engineering# 7 Heat Transfer Su Yongkang School of Mechanical Engineering Convection overview • Consider a flat plate of length L, in air flow with velocity u∞ and temperature T∞ • Local heat flux is: where h is the local heat transfer coefficient • Total heat transfer rate: ( ) = − ∞ q ′′ h Ts T ∫ ∞ ∫ = ′′ = − s As s s A s q q dA (T T ) hdA ( ) q = hAs Ts −T∞ average heat transfer coefficient h = Determination of ‘h’ will rely on analytical as well as empirical data