Abstract: ased on Jorgenson's effective velocity formula a hot-wire response equation of the third order is derived,which is used to analyze the mean velocities as well as Reynolds stresses under the condition of low speed keeping constant density.The co-axis between the probe axis and measured velocity vector is not needed with this method,thus simplifying the traverse mech-anism. Most calibration equations are implicit functions of the velocity.In order to avoid solving an ultra-equation for the transfer of anemometer output into effective velocity,explicit hot-wire calibration equations are goven,which reduces computer time and still keeps the high precision.

Key words: three dimensional flow, turbulent flow, hot-wire anemometers, turbulence meter, calibrating