This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transform...This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transformation(DTM) and finite difference(FDM) methods is utilized to theoretically study the present problem.DTM and FDM are applied to the time and space domains of the problem,respectively.The accuracy of this method solution is checked against the numerical solution.Then,the effects of some applicable parameters were studied comparatively.Since a broad range of governing parameters are investigated,the results could be useful in a number of industrial and engineering applications.展开更多
采用直接模拟蒙特卡洛(direct simulation Monte Carlo,DSMC)方法对2个无限大平行平板之间的稀疏单原子气体一维热传导问题进行数值模拟,以探索不同稀薄程度条件下平板之间的气体压力、密度和温度的分布特征,获得导热系数随着温度的变...采用直接模拟蒙特卡洛(direct simulation Monte Carlo,DSMC)方法对2个无限大平行平板之间的稀疏单原子气体一维热传导问题进行数值模拟,以探索不同稀薄程度条件下平板之间的气体压力、密度和温度的分布特征,获得导热系数随着温度的变化关系。结果表明:传热建立稳态后平板之间的气体压力是均匀的,且与初始Knudsen数成反比,冷端(下方平板)附近的气体密度较大,Knudsen数较小,属于连续流动,热端(上方平板)附近的气体密度较小,Knudsen数较大,属于滑移流动。上下方平板附近均存在温度跳跃现象,初始Knudsen数越大,温度跳跃越明显,下方平板温度跳跃较小,上方平板温度跳跃较大。在所考虑的压力范围内,导热系数与气体压力无关,仅仅是气体温度的幂律函数,且导热系数的DSMC模拟结果与现有文献中的数据一致,验证了结果的可靠性。展开更多
文摘This work focuses on transient thermal behavior of radial fins of rectangular,triangular and hyperbolic profiles with temperature-dependent properties.A hybrid numerical algorithm which combines differential transformation(DTM) and finite difference(FDM) methods is utilized to theoretically study the present problem.DTM and FDM are applied to the time and space domains of the problem,respectively.The accuracy of this method solution is checked against the numerical solution.Then,the effects of some applicable parameters were studied comparatively.Since a broad range of governing parameters are investigated,the results could be useful in a number of industrial and engineering applications.
文摘采用直接模拟蒙特卡洛(direct simulation Monte Carlo,DSMC)方法对2个无限大平行平板之间的稀疏单原子气体一维热传导问题进行数值模拟,以探索不同稀薄程度条件下平板之间的气体压力、密度和温度的分布特征,获得导热系数随着温度的变化关系。结果表明:传热建立稳态后平板之间的气体压力是均匀的,且与初始Knudsen数成反比,冷端(下方平板)附近的气体密度较大,Knudsen数较小,属于连续流动,热端(上方平板)附近的气体密度较小,Knudsen数较大,属于滑移流动。上下方平板附近均存在温度跳跃现象,初始Knudsen数越大,温度跳跃越明显,下方平板温度跳跃较小,上方平板温度跳跃较大。在所考虑的压力范围内,导热系数与气体压力无关,仅仅是气体温度的幂律函数,且导热系数的DSMC模拟结果与现有文献中的数据一致,验证了结果的可靠性。
