A new numerical technique named interval finite difference method is proposed for the steady-state temperature field prediction with uncertainties in both physical parameters and boundary conditions. Interval variable...A new numerical technique named interval finite difference method is proposed for the steady-state temperature field prediction with uncertainties in both physical parameters and boundary conditions. Interval variables are used to quantitatively describe the uncertain parameters with limited information. Based on different Taylor and Neumann series, two kinds of parameter perturbation methods are presented to approximately yield the ranges of the uncertain temperature field. By comparing the results with traditional Monte Carlo simulation, a numerical example is given to demonstrate the feasibility and effectiveness of the proposed method for solving steady-state heat conduction problem with uncertain-but-bounded parameters.展开更多
A system method is proposed to analyze pinch change of heat exchange problems with uncertain stream flowrates and temperatures. By an analysis of the maximum heating point and maximum cooling point of uncertain parame...A system method is proposed to analyze pinch change of heat exchange problems with uncertain stream flowrates and temperatures. By an analysis of the maximum heating point and maximum cooling point of uncertain parameters, existence of pinch jump can be determined. Based on the principle of reduced temperature interval analysis, a sufficient and necessary condition is derived for each stream supply temperature to determine if it is possible to become pinch within the specified range of uncertain parameters, then this range may be partitioned into different pinch regions. The study is a foundation for the flexibility analysis, synthesis, and retrofit of heat exchanger networks.展开更多
基金supported by the National Special Fund for Major Research Instrument Development(2011YQ140145)111 Project (B07009)+1 种基金the National Natural Science Foundation of China(11002013)Defense Industrial Technology Development Program(A2120110001 and B2120110011)
文摘A new numerical technique named interval finite difference method is proposed for the steady-state temperature field prediction with uncertainties in both physical parameters and boundary conditions. Interval variables are used to quantitatively describe the uncertain parameters with limited information. Based on different Taylor and Neumann series, two kinds of parameter perturbation methods are presented to approximately yield the ranges of the uncertain temperature field. By comparing the results with traditional Monte Carlo simulation, a numerical example is given to demonstrate the feasibility and effectiveness of the proposed method for solving steady-state heat conduction problem with uncertain-but-bounded parameters.
文摘A system method is proposed to analyze pinch change of heat exchange problems with uncertain stream flowrates and temperatures. By an analysis of the maximum heating point and maximum cooling point of uncertain parameters, existence of pinch jump can be determined. Based on the principle of reduced temperature interval analysis, a sufficient and necessary condition is derived for each stream supply temperature to determine if it is possible to become pinch within the specified range of uncertain parameters, then this range may be partitioned into different pinch regions. The study is a foundation for the flexibility analysis, synthesis, and retrofit of heat exchanger networks.
