Thermal design of cooler in the fuel handling pneumatic system of RDE

Abstract

A small size reactor called Reaktor Daya Eksperimen (RDE) is being designed by BATAN. The nuclear reactor with the power of 10 MWt based on the High Temperature Gas-Cooled Reactor (HTGR) type. The helium gas with high temperature is used to remove the heat generated from the reactor core. Therefore, the helium gas as primary cooling system of reactor is high temperature. The typical of reactor cooling system is that the primary coolant system pressure should be lower than the secondary coolant pressure. In order to load a nuclear fuel pebble into the reactor core, a fuel handling system (FHS) is applied. In the FHS, a carrier gas of pneumatic system is important to blow the fuel pebbles. The objective of the research is to calculate the thermal design of cooler heat exchanger in which the high temperature of helium gas as carrier gas is reduced to be lower temperature. In this case, a cooler is used to cool the helium gas by coolant water. Based on the specification data requirement to calculate the thermal design of cooler, the ChemCAD.6.1.4 software was performed. A shell-tube type of heat exchanger has been determined to reduce the temperature of helium gas from 250°C to be less than 60°C at pressure of 30 bars. The water as a coolant is passed into the shell-side at temperature of 28°C. In the design calculation, it has carried out through a various consideration on aspects of safety as well as optimization. The result of thermal design are as follows: the heat exchanger of shell-tube type using fixed tube sheet with heat duty of 0.3122 MJ/s, the coolant water mass flow rate is 3.55 kg/s, surface area for heat transfer is 51.4471 m2 and Log Mean Temperature Difference (LMTD) is 81.53°C. Furthermore, the design result requirement of heat exchanger based on the specification, design tolerance and manufacture in appropriate with the TEMA standard of shell-tube type. The thermal design of cooler in the carrier gas of pneumatic system is expected to provide the design of FHS.