An Experimental Study of Natural Convection in an Inclined Rectangular Cavity Filled With Water at Its Density Extremum

An experimental investigation pertaining to the effect of the density inversion of water on steady natural convective flow patterns and heat transfer in an inclined rectangular cavity whose two opposing walls are kept at different temperatures is carried out. Water as a testing fluid has its maximum density at about 4 °C. The temperature of one wall is maintained at 0 °C, while that of the opposing hot wall is varied from 2 to 20 °C. Photographs of the flow patterns, temperature distribution in the water layer, and average Nusselt number are presented under various hot wall temperatures and inclination angles of the cavity. The present results could indicate that the density inversion of water has an influential effect on the natural convective heat transfer in the prescribed water layer. Moreover, the average Nusselt number is a peculiar function of the temperature difference between the cold and hot walls and inclination angle, unlike the previous results for common fluids without density inversion.