关键词: 月桂酸, 环形单元, 熔化, 传热机制, 数值模拟

Abstract:

Numerical investigations on the melting process of lauric acid in a horizontal annulus heated isothermally from the inside wall is presented. The simulation is verified by comparing with the results by experiment. The mechanism of heat transfer of the melting process is analyzed through the melting phase front and the average Nusselt changes with Fourier number in different boundary temperatures. The result shows that the average Nusselt decreased with the increase in Fourier number first, and then decreased gradually, the lowest point before the average Nusselt changes with Fourier number in different boundary temperatures. The result shows that the average Nusselt decreased with the increase in Fourier number first, and then decreased gradually, the lowest point before the average Nusselt increased is the transition point of heat transfer mechanism. A clear separation of melt fraction curve is manifested in comparison with the pure heat conduction model diagram. It is found that the Fourier number of the transition point from pure heat conduction to natural convection is 0.028 when Rayleigh number and Stefan number are 1.33×10⁷, 0.206 respectively.

Key words: lauric acid, annulus unit, melting, heat transfer mechanism, numerical simulation