Design of steady state test apparatus to evaluate heat transfer coefficient of spray

Recent years have seen a change in the emphasis on the importance of strip cooling on the hot strip mill as it has been realised that the rate of cooling affects the metallurgical and mechanical properties of the finished strip. The degree of cooling applied both between the finishing stands and on the runout table depends on the grade of steel being produced. To meet customers' demands for increased quality and product consistency, together with the production of a wider range of steels, there is a need for accurate temperature control throughout the whole cooling path. This requires a cooling system that couples the required cooling rate with the heat transfer capabilities of the spray system and the production speed and line length. The current work, being undertaken as an Engineering Doctorate project, considers the heat transfer capabilities of various water cooling systems. This paper is an interim report which describes the design of steady state heat transfer apparatus to evaluate the heat transfer coefficient of a single spray and presents some preliminary results.