Double-pipe heat exchanger with diffuser channels

The numerical modeling of heat transfer in double-pipe heat exchangers with diffuser channels with small expansion angles is performed using a three-parameter differential turbulence model supplemented with a transfer equation for a turbulent heat flux. It is shown that due to the intensification of the heat transfer in heat exchangers with diffuser channels, the amount of heat transferred from the hot heat-transfer liquid to the cold one increases in comparison with heat exchangers with channels of a constant cross section.