抄録
An attempt is made for simultaneous, but independent control of skin friction reduction and heat transfer enhancement in a turbulent channel flow. First, a mathematical relation is derived of the contribution of turbulent heat flux to the Nusselt number. Two different thermal boundary conditions are considered: (1) isothermal condition, where two walls are kept at constant, but different temperatures; (2) isoflux condition, where both walls are heated at a given wall heat flux. By focusing on the difference between the derived relation and the similar relation for the skin friction (Fukagata et al., 2002), a strategy for the simultaneous control is proposed. The effects of the control strategy are examined by means of direct numerical simulation.