Basic concepts-thermal considerations 2. Newtons law of cooling qy=h(T。-Tmn Not constant Here, the mean t plays the same role as the free stream T for external flows 3. Fully developed conditions because of heat transfer, T(r) is continuousl changing with X can fully developed conditions be reached?? For thermally fully developed 0|T(x)-7(r,x) 0 OxLT。(x)-Tm(x) fa, t Although the temperature profile t(r) changes with x, the relative shape of the profile no longer changes Heat Transfer Su Yongkang School of Mechanical EngineeringHeat Transfer Su Yongkang School of Mechanical Engineering # 5 Basic concepts—thermal considerations • 2. Newton’s law of cooling • Here, the mean T plays the same role as the free stream for external flows. • 3. Fully developed conditions because of heat transfer, T(r) is continuously changing with x. can fully developed conditions be reached?? • For thermally fully developed • Although the temperature profile T(r) changes with x, the relative shape of the profile no longer changes. ( ) qs = h Ts −Tm  T Not constant! 0 ( ) ( ) ( ) ( , ) ,  =      − −   m f d t s s T x T x T x T r x x