Thermal Flow Measurements at Gr/Re by Silicon Anemometry

We present the first characteristics of air flow measurements in the mixed convective region with strong buoyancy effects (Gr/Re 1), using a thermal silicon double-Wheatstonebridge vector sensor. The Alternating Direction Method is applied to eliminate additive drift influences. The upper limit on the mixed convective region is experimentally defined to be given by Gr/Re = [0:3–0:8]. Flow velocity measurements of down to 1 mm/s (Reynolds 0.3) are realized with an accuracy better than 98%.