The feasibility of hot wire anemometer in to a new measurement configuration is demonstrated in this work and we validate our results by a numerical model. We have created an anemometer probe with hot wire using a new scheme, in alternate current and synchronic detection (3ω method). We use this instrument to register the velocity magnitude in boundary layer for a forced convection flow. The probe and its alimentation also the measuring support and bridge Wheatstone, have been created by us. The physical parameter was recorded is an exchange heat quantity between hot wire and fluid flow. In steady state, experimental data verify the numerical results with an average error of 3%.