COMBINED LASER-DOPPLER AND COLD WIRE ANEMOMETRY FOR TURBULENT HEAT-FLUX MEASUREMENT

A combined laser-doppler and cold wire anemometry technique for determ ining turbulent heat flux is described. The system can be used in flow s of arbitrarily high turbulent intensity and large temperature variat ions. Its potential is demonstrated via measurements in a simulated st able atmospheric boundary layer, for which the Monin-Obukhov length sc ale was about 70% of the boundary layer depth. Mean and turbulence pro perties were obtained throughout the boundary layer and the results ar e shown to be both internally consistent and similar to corresponding field data. Measurements in the highly turbulent, separated flow behin d a bluff body mounted in the stable boundary layer are also presented .