Transient conjugated heat transfer from a rectangular hot film

A numerical calculation is carried out for the transient response of a flush-mounted hot-film sensor in a gas flow heated by a step change in the hot-film output flux. The numerical method used is called the unsteady surface element method. This calculation is part of a study of unsteady behavior of hot-film anemometers that involve substrate effects. The numerical results show that the early-time film temperature agrees well with an analytical solution, and the steady-state Nusselt number agrees with an existing numerical solution. The spatial average film temperature vs time is presented for several values of the rectangular hot-film aspect ratio. (Author)