Journal Article

Evolution of Temperature Field around Underground Power Cable for Static and Cyclic Heating

Shahbaz Ahmad, Saiful Islam, Zarghaam Haider Rizvi, Joan Chetam Christine Arp, Vineet Tirth, Frank Wuttke

2021

Overview

Power transmission covering long-distances has shifted from overhead high voltage cables to underground power cable systems due to numerous failures under severe weather conditions and electromagnetic pollution. The underground power cable systems are limited by the melting point of the insulator around the conductor, which depends on the surrounding soils’ heat transfer capacity or the thermal conductivity. In the past, numerical and theoretical studies have been conducted based on the mechanistic heat and mass transfer model. However, limited experimental evidence has been provided. Therefore, in this study, we performed a series of experiments for static and cyclic thermal loads with a cylindrical heater embedded in the sand. The results suggest thermal charging of the surrounding dry sand and natural convection within the wet sand. A comparison of heat transfer for dry, unsaturated and fully saturated sand is presented with graphs and colour maps which provide valuable information and insight of heat and mass transfer around an underground power cable. Furthermore, the measurements of thermal conductivity against density, moisture and temperature are presented showing positive nonlinear dependence.

• Publisher: MDPI AG
• Subject: Boundary conditions / Cables / convection in porous media / cyclic thermal loading / Experiments / Heat conductivity / Heat transfer / Humidity / Laboratories / Moisture content / Numerical analysis / Partial differential equations / Precipitation / T / Technology / Temperature / thermal conductivity / underground power cable / underground power cable; cyclic thermal loading; convection in porous media; vadose zone heat transfer; thermal conductivity / vadose zone heat transfer / Wind