Optimal Design and Experimental Study of Ejector for Ladle Baking

Abstract

Current regenerative ladle preheating devices for steel plants are supposed to be equipped with an induced draft fan to suction high‐temperature flue gas, which flows through the regenerator and heats it simultaneously. Replacing the traditional draft fan of ladle preheaters with high‐pressure air of steel plants and ejectors is of great significance in energy conservation and emission reduction. The influence of the ejector nozzle diameter, nozzle to throat clearance, diffuser chamber structure, and primary gas inlet pressure on the ejector performance is analyzed through a combination of establishing a three‐dimensional ejector model and simulation work with the numerical simulation software Fluent. The optimal ejector design parameters are proposed and validated using experimental data. The research showed that the ejector can achieve the best performance with the parameters of 0.42 MPa inlet pressure for high‐pressure primary gas, 0.027 m ejector nozzle diameter, 0.11 m nozzle to throat clearance, 8° divergence angle of the diffuser, and 0.19 m length of diffuser chamber. The entrained mass flow rate of the secondary gas is 1.14 kg s−1 for the optimal ejector. The experimental results are consistent with those of the numerical simulation and verified that the optimal design of ejector device met the practical requirements.