Crosswinds effect on the performance of natural draft wet cooling towers

Abstract

Effects of crosswinds on the thermal performance of natural draft wet cooling towers (NDWCTs) have been investigated. A three-dimensional CFD model has been used to determine the effect of crosswinds on NDWCTs performance surrounded by power plant building structures. The three-dimensional CFD model has utilized the standard k– ɛ turbulence model as the turbulence closure. Two cases have been investigated: a stand-alone NDWCT and two NDWCTs within a proposed power plant structures (PPS). It has been found that regardless of the crosswinds direction, an increase of 1.3 k or more could be predicted at crosswinds speeds greater than 4 m/s. Furthermore, the performance of NDWCTs under crosswinds has been found to be dependent on the three major factors: the structure of the approaching crosswinds and whether it is disturbed or undisturbed, the location of the NDWCT in the wake of the other NDWCT, and the location of the NDWCT in front of/in the wake of the PPS. When comparing results from the stand-alone and from the NDWCTs within PPS simulations, differences in Δ T wo were found to be less than 1 K for the whole span of crosswinds speeds and could be decreased to 0.7 K for speeds less than 8 m/s. Finally, results obtained from the simulation of a stand-alone NDWCT could be used instead of those from NDWCTs within PPS at a certain crosswinds direction for qualitative comparisons.