Pool boiling of deionised water over polyurethane coated surfaces

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.Preliminary investigations are done to cater the possibility of the use of the polyurethane coating for the pool boiling heat transfer augmentation. Experiments have been done on the bare stainless steel heater and stainless steel heaters coated with polyurethane coatings of different thicknesses, by boiling deionised water at constant atmospheric pressure. Contact angle formed by the deionised water over the test specimen are experimentally measured and from these values the solidliquid surface energy values have been calculated. It has been found that the polyurethane coating has increased the solidliquid surface energy and the heat transfer. Recommendations for the future inspections with relevance to finding an ideal heat transfer enhancer coating are putforth.