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An analytical model using finite element approximation was applied to determine the amount of heat dissipated in a three-body graphite calorimeter used in the field of dosimetry. The temperature drifts and the heat dissipation of the calorimeter bodies via conduction and radiative transfer during electrical heating were considered to enhance heat insulation for the accurate measurement of absorbed dose. A simulation was applied to the heating and cooling process for both electrical calibration and irradia- tion. The heat transfer in the calorimeter bodies and wire could be first estimated quantitatively. The radiation energy absorbed into the core during irradiation was estimated in a heat-loss-compensated mode of operation, and the effects of the wire conduction of the thermistor on the radiant heat loss were investigated.
Electrical heating, finite element method, graphite calorimeter, heat transfer, radiation energy
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