Numerical Study on Effect of Nozzle Diameter on Plate Cooling in Run Out Table of Hot Plate Rolling Process

Abstract

The design of cooling systems for running hot steel plates has received much attention because the mechanical and/or metallurgical properties of final products are greatly influenced by the cooling capacity of the system. Thus many steel makers have largely concentrated on simply increasing the cooling water supply capacity of the system. Some researchers believe that plate cooling is a type of thermal communication between the hot plate and the cooling water or the atmosphere, so they have emphasized the importance of thermal conditions such as the cooling water temperature or air humidity. Actually the cooling process is governed by the basic physics of boiling heat transfer between the hot steel plate and the cooling water. Therefore steel makers should be more concerned about the influence of the design parameters of cooling facilities on the boiling phenomenon rather than the simple increase of the cooling water flow rate. In this study, when the diameter of the nozzle supplying cooling water is changed, its effect on boiling heat transfer has been investigated numerically. The average heat flux, the Leidenfroststeam-layer thickness, the temperature drop and so on were investigated according to nozzle diameter.

Heat transfer characteristics and cooling capacity of online quenching equipment for plate

“…8 The effect of changing the diameter of the nozzle supplying cooling water on boiling heat transfer has been investigated numerically. 9 So the simulated method helped research the heat transfer characteristics of new equipment, and the experimental method could be applied to verify the simulation results.…”

“…In the process of online quenching, the heat transfer of steel plate mainly includes convection heat transfer between high-temperature steel plate and cooling water, radiation of steel plate to the environment, and heat conduction between steel plate and transport roller table. Compared with the convection heat transfer, the radiation and heat conduction are very small 9 and can be ignored. So the convection heat transfer is deserved more attention than radiation and heat conduction.…”

Experimental and Numerical Study of Twin Circular Water Jets Impinging on a Moving Thin Film

“…Because precise temperature control of steel sheets is essential to making high-quality products, the heat transfer characteristics of this cooling process have been studied extensively through both experiments [1][2][3][4] and numerical simulations. [5][6][7][8] In ROT cooling, a large amount of water impinges upon a moving steel sheet to form a thick water film over the solid sheet. Therefore, most of the circular water jets in an array impinge not on the dry hot steel sheet but on the pre-existing liquid film.…”

Numerical Study of the Effect of Nozzle Arrangement on Cooling Process in Running Hot Steel Strip after Hot Rolling

“…In our study, based on previous numerical works, [10][11][12] we conducted numerical simulations of the cooling process to investigate the effects of the nozzle arrangement on the cooling process. Inline and staggered nozzle arrangements were adopted in this study.…”