Estimating decay heat removal rate by natural convection for Tehran Research Reactor

• Published in: Progress in nuclear energy (New series) Vol. 54; no. 1; pp. 191 - 195
• Main Author: farhadi, Kazem
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2012; Elsevier
• Subjects: Applied sciences; Approximation; Channels; Computational fluid dynamics; Coolants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Heat transfer; High temperature ratio; Installations for energy generation and conversion: thermal and electrical energy; Integrals; Mathematical models; MTR research reactor; Natural convection; Non-Boussinesq model; Non-uniform heat flux; Nuclear fuels; Nuclear research reactors; Preparation and processing of nuclear fuels; Theoretical studies. Data and constants. Metering; Variable physical properties; High temperature ratio; Non-uniform heat flux; MTR research reactor; Natural convection; Non-Boussinesq model; Variable physical properties; Conduction; Fuel cycle; Heat flow; Velocity distribution; High temperature; Modeling; Heat flux; After-heat; Boundary layer; Temperature distribution; Coolant; Nuclear fuel; Physical properties; Nuclear reactor; Equation system; Storage; Accident; Research reactor; Heat transfer
• ISSN: 0149-1970
• DOI: 10.1016/j.pnucene.2011.05.029

An integral boundary layer model is developed in that both the Boussinesq and non-Boussinesq approximations are taken into consideration. The model analyzes laminar free convection between nuclear fuel plates having large aspect ratio. The coolant channels are subject to a uniform as well as non-uniform, symmetric, heat flux and varying fluid properties. In the model the flow is assumed to be fully developed which is a good assumption for channels with large aspect ratios. The non-Boussinesq approximation is introduced into the integral boundary layer equations governing the system to describe the velocity and temperature distributions of the coolant in the cooling channels. The fuel plate temperature is related to the adjacent coolant fluid temperature by a fundamental law in conduction heat transfer. Water is considered as the working fluid. The results show that the present heat transfer problem encountered in nuclear research reactor such Tehran nuclear research reactor is characterized by high temperature ratios and thereby rendering the commonly applied Boussinesq approximation invalid. The non-Boussinesq results presented in the work are particularly useful for design and accident analysis of nuclear fuel during the storage cycle. ► A non-Boussinesq integral model is developed for Tehran Research Reactor. ► Numerical solution to this integral model is provided. ► The numerical solution approach exact solution asymptotically.