Direct Air Cooling of Pipe-Type Transmission Cable for Ampacity Enhancement: Simulations and Experiments

Amid the growing demand for energy supply in modern cities, the enhancement of transmission capacity is receiving considerable attention. In this study, we propose a novel method of direct forced cooling in pipe-type transmission lines via an external air supply for reducing the cable temperature and enhancing the ampacity. We conducted numerical simulations using computationally efficient two-dimensional models and a reduced-length three-dimensional model for assessing the cooling efficiency, the distance required for temperature convergence, and the fan/pump capacity required for forced air cooling. We found a 26% increase in ampacity in the case of 5 m/s inlet air velocity into the pipe conduit. We also built and tested the experimental setup equipped with a 300 m length model transmission cable. Results of the forced air cooling experiments show good agreement with numerical simulations. To the best of our knowledge, this study demonstrates the first analysis and validation of direct cooling in pipe-type cables, presenting a promising path for efficient power management in modern metropolitan areas.