AN EXPERIMENTAL RESEARCH ON THE EFFECT OF THE AXIAL POWER DISTRIBUTION ON THE CRITICAL POWER

摘要

In this paper, an experimental research on the effect of the axial power distribution on the critical power is performed under the atmospheric pressure with using a circular tube. The circular tube is axially divided into 3 insulated levels and is heated separately by 3 DC power suppliers. Axial uniform heating condition, the upper three-layer simulation and the center three-layer simulation of the double-humped core of Innovative Water Reactor for Flexible Fuel Cycle (FLWR) are selected as the cases for the detailed evaluation. The effects of relative power ratio on the critical power, the critical quality and the critical boiling length under different heating conditions are ascertained for the detailed evaluation cases. With using the experimental data, existed correlating methods for the boiling transition are evaluated. As the result, a combination of the critical quality-boiling length (x_(BT)- L_B) method and the critical heat flux-critical quality (q_(BT)-x_(BT)) method is found a good correlating to the present data with a changed axial power distribution.