Nonstationary convective heat transfer in rectangular cross section channels

Non-stationary problems of convection heat exchange in channels with a rectangular cross section in the case of boundary conditions of the third kind, as well as in the case of variable heat exhange over the perimeter of a heat current on the wall, are solved. The edge problems of a non-stationary heat exchange during the liquid flow in a channel of a rectangular cross section is drawn to the integration of the energy equation. As results have shown, Nu number values differ insignificantly from corresponding values, obtained when solving analogous problems i when the wall temperature is given (boundary conditions of the first kind). The above approach to the solution of problems permits to obtain results for channels of other forms of cross section, as well; to investigate the effect of non-stationarity, geometry, boundary conditions and other parameters on the process of heat exchange, to solve problems when accounting energy dissipations in a current, with the presence of heat sources