CONTROLLING THERMOMECHANICAL CHARACTERISTICS OF GAS FLOWS IN THE TURBOCHARGER OUTLET DUCT

The author has obtained data on gasdynamic and heat-transfer characteristics of nonstationary fl ow of a gas in
the outlet duct of the centrifugal compressor of a turbocharger for supercharging piston engines. It has been shown
that an equalizing grid installed in the outlet duct of the turbocharger centrifugal compressor reduces 2 to 3 times
the amplitude of pulsations of the gas-fl ow velocity in this duct, decreases its turbulence by 30%, and enhances
heat transfer in the duct by 13–25% compared to the basic duct without a grid. It has been established that cutting
grooves in the indicated channel leads to an increase of 9–12% in the gas turbulence in it; the local coeffi cient of
heat transfer in this duct increases 35% compared to the basic duct. Based on the numerical modeling of processes
occurring in the piston-engine′s turbocharger, the authors has demonstrated a positive eff ect from the equalizing grid
being installed in the outlet duct to the turbocharger centrifugal compressor and from the grooves being cut on its
walls, which consists in increasing the power of the engine by 2% and its effi ciency, by 0.25%.
   
Author:  L. V. Plotnikov
Keywords:  turbocharger, centrifugal compressor, piston engine, gasdynamics, heat transfer, effi ciency indices.
Page:  734