Numerical Simulation and Structure Optimization of Converter Gas Evaporative Cooler

In Lurgi-Thyssen dedusting system of steelmaking converter, the evaporative cooler represents a crucial operating unit, in which the hot dust-laden flue gas has to be cooled by saturation with water. The cooling process of the gas consists of gas-liquid two phase flow and interphase heat and mass transfer. In this paper, k-epsilon standard equations and Lagrange discrete phase model are employed to describe the gas turbulent flow and the heat/mass transfer with droplet evaporation individually. The computational fluid dynamics (CFD) simulation for practical engineering project shows that the large-flux cooling gas is commonly constructed in a non-uniform flow caused by the sharp turnings at the inlet and outlet channels. The unevenness of velocity distribution and the effective cooling height are defined in this paper to evaluate the cooling flow process. A series of newly designed structures with guide plate are investigated by CFD method to eliminate the problems with the non-uniformity. The results of numerical simulation show that optimal designed guide ring plate could improve the flow uniformity and the heat transfer. The investigations have been used to guide the engineering application.