Quasi-two-dimensional numerical model for stability simulation of a cable-in-conduit conductor

We have developed numerical code for stability simulation of a cable-in-con duit conductor (CICC), POCHI, resulting in improved accuracy in stability s imulation. However, there still remains some degree of error in evaluation for removing heat from the strand to the coolant because of limitations of the analytical model. In the new model, coolant temperature is calculated o n two-dimensional grids in the effective thermal boundary layer around the strand, in which the coolant temperature changes from the strand temperatur e to that of the coolant main flow, neglecting the effect of coolant convec tion and heat conduction in the conductor axis direction. (Our model is the n called 'quasi-two-dimensional'.) In addition, a non-uniform mesh system i s applied for numerical calculation to reduce computational (CPU) time. The simulation results obtained by using POCHI and an improved version (POCHI2 ) were compared with the experimental results of stability for a small CICC for verification of the codes. Both simulation results were in good agreem ent with those of the experiment in the magnitude. However, dependence of t he stability calculated by POCHI on the initial coolant flow rate had some inconsistencies with the experiment. These inconsistencies could be removed by the use of POCHI2 with a reasonable increase, only a few times longer, in CPU time. These results verify the validity of POCHI2. (C) 1999 Elsevier Science Ltd. All rights reserved.