Investigation of the Cooling System Condenser Fans Performance at Different Speeds of Subway Train

Document Type : Research Article

Authors

Department of Mechanical Engineering, Hakim Sabzevari University, Sabzevar, Iran

Abstract

In the present work to evaluate the cross wind flow effects due to the subway train motion on efficiency of condenser fans in air conditioning system, the behavior of fluid have been studied. Velocity profiles in output fan, temperature variations at near fan were studied at different velocity of train. In numerical analysis, for the turbulent and incompressible flow, Navier-Stokes and energy equations and k‑ε turbulence model has been used for modeling of turbulent flow. Variations of temperature and velocity of outflow of the fan at horizontal and vertical directions and the effective length as outflow guidance of the fan in opposite direction of train at difference velocity of train have been reported. At high velocity of train, negative output velocity of the fan and high effective length have been observed. Dimensionless effective length in high velocity of train at height of 10 and 20 cm were obtained 0.528 and 0.951 respectively. Finally, a parameter that is heat transfer rate to maximum heat transfer rate at height of 10 cm is defined which maximum amount is 5.88 percent. Due to the prevailing crosswind flow on the outflow of the fan, this parameter reduces.

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Main Subjects


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