Thermal-hydraulic analysis of heated plate under asymmetrical cooling conditions

الملخص EN

The cooling of a vertical heated plate by two thin channels is encountered in different applications such as MTR research reactors.

The analytical solution of the governing equation of such case is usually used provided that symmetricity of the cooling channels is assumed.

Under asymmetrical cooling conditions the analytical solution is impossible and the numerical solution becomes the only way.

This problem is our case study in which the finite difference method is used to convert the steady state governing equation into a number of algebraic equations which are solved by Gauss Jordan’s method.

The coolant flow distribution through the channels is determined based on an equal overall pressure drop in the two channels.

The axial power distribution through the plate is considered cosine shape.

Therefore, a simple one-dimensional steady state computer FORTRAN program named NSCHP is built to deal with the asymmetrical cooling conditions encountered in MTR research reactors resulting from fuel manufacturing uncertainties.

This program has the capability to calculate the axial and radial temperature distribution in the plate, the coolant axial temperature, the flow distribution, the coolant velocity, and the channel pressure drop.

The introduced program is verified by comparing its results with the RELAP5 mode 3.3 where a good agreement was found.

With respect to the channel blockage or manufacturing uncertainties, the results show that an inadvertent decrease in channel cross section up to 82.5% of the nominal channel do not violate the approved maximum cladding temperature.