Use of guide vanes for improvement of flow pattern and enhancement of thermal performance of dry cooling towers

Department of Mechanical Engineering, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran

^a Corresponding author: Ranjbar@irost.ir

Received: 25 April 2015
Accepted: 21 October 2015

Abstract

Environmental factors, such as cross winds, adversely affect the performance of a dry cooling tower. In this field study, use of a guide vanes cascade for improvement of thermal performance of a dry cooling tower has been investigated. A four-vane cascade was installed at a delta in a critical sector of the cooling tower and effects on flow pattern through the delta and subsequent enhancement of thermal performance of the radiators in the delta were evaluated. Results show that the use of guide vanes cascade at the delta eliminates the vortex shape flow conditions at the delta inlet, improves flow rate through the deltas by about 35% and reduces the average temperature distribution on the radiators surfaces by about 1.9 °C, which is the equivalent to the amount of reduction in water temperature at the radiators outlet. The results further show that the use of guide vanes cascades in all the affected deltas in the critical sectors would result in a 7% increase in the overall thermal performance of the investigated cooling tower.