Effects of aspect ratio on natural convective heat transfer from a vertical isothermal cylinder immersed in cold pure water

저온의 순수물속에 잠겨있는 등온수직 원기둥에 의한 자연대류 열전달에 종횡비가 미치는 영향

A numerical analysis is performed about the effects of aspect ratio on natural convective heat transfer from a vertical isothermal cylinder of 0.deg. C immersed in cold pure water. The results of analysis include velocity profiles, temperature profiles and mean Nusselt number of the steady flow region. As aspect ratio of vertical cylinder increases, the flow and heat transfer characteristics of vertical isothermal cylinder approach to those of vertical isothermal flat plate. Numerical solutions obtained for Rayleigh number and aspect ratio indicate the cylinders can be classified as short cylinder and long cylinder. In the cases of short cylinder and long cylinder, new heat transfer correlations are presented. Here, the coefficient values C of new heat transfer correlations are presented as the function of density extremum parameter $R^*/. Numerical results show that theoretical results are in close agreement with experimental results.ts.