Explaining boiling beyond the boiling temperature

Project: Research direct


On the run-out table of steel mills, steel is cooled by a large number of water jets. The strength, quality and consistency of the steel depend on the cooling trajectory. Presently, this cooling trajectory is hard to predict, since the cooling process by the water jets is not well understood and correlations for the heat transfer coefficient are not available. The reason for this is that different boiling regimes, such as film boiling and rewetting, are alternating and this also depends on the surface roughness of the steel plate. In our laboratory we study this cooling process experimentally. To this end direct observations of the highly time-dependent and complex topology of the two-phase flow of water and vapor above the plate are made by means of a borescope, which looks through the water jet onto the steel plate. Apart from that, visualizations are made from the side and the temperature is measured at several locations inside the steel plate close to its surface, from which the heat flux through the surface can be determined by solving the inverse heat problem. This can be done for varying temperatures of the steel plate (up to 700 C) and varying water temperature and surface roughness.In a run-out table in industry the steel plate is moving with rather high velocity through a series of water jets. In order to investigate the effects of this movement, the experimental set-up also allows the steel plate to move with a velocity up to 8 m/s.This project is carried out in close collaboration with Tata Steel.
People involved in this project: Hans Kuerten & Bart van Esch
Short titleCooling of steel in steel mills
Effective start/end date1/07/1630/06/20