Virtual Testing and Simulation Methods for Aerodynamic Performance of A Heavy Duty Cooling Fan

Aerodynamic performance testing of heavy duty fans involve complicated test setups with specialized equipment and measurement systems as summarized in ANSI 210-07 standard. This paper describes virtual testing and simulation methods to obtain the fan aerodynamic performance data using commercial Computational Fluid Dynamics (CFD) software. Two different virtual test environments were used during the analysis. The first one is a virtual test chamber which is constructed based on the actual fan system installation. The second one is a virtual flow tube which approximates a fan flow test set-up as outlined in ANSI 210-07. The virtual fan is created from (i) the laser scan of the actual fan and (ii) the design specifications of the fan. The virtual test conditions simulate the actual test arrangement by imposing free boundary at flow inlet/outlet and proper fan rotation. The aerodynamic flow rate is controlled by a variable orifice located at the virtual test chamber outlet. In the simulations, the flow rate and pressure rise across the fan are obtained by integrating the appropriate variables across virtual cross sections at specific locations. The virtual performance curve is obtained by simulating the flow conditions at various outlet orifice settings. The virtual performance curve will be compared with the actual performance curve.