000K utf8 1100 $c2021 1500 eng 2050 urn:nbn:de:gbv:8:3-2022-00040-3 2051 10.3390/en14238191 3000 Ahmad, Shahbaz 3010 Arp, Joan Chetam Christine 3010 Islam, Saiful 3010 Rizvi, Zarghaam Haider 3010 Tirth, Vineet 3010 Wuttke, Frank 4000 Evolution of Temperature Field around Underground Power Cable for Static and Cyclic Heating [Ahmad, Shahbaz] 4209 Power transmission covering long-distances has shifted from overhead high voltage cables to underground power cable systems due to numerous failures under severe weather conditions and electromagnetic pollution. The underground power cable systems are limited by the melting point of the insulator around the conductor, which depends on the surrounding soils’ heat transfer capacity or the thermal conductivity. In the past, numerical and theoretical studies have been conducted based on the mechanistic heat and mass transfer model. However, limited experimental evidence has been provided. Therefore, in this study, we performed a series of experiments for static and cyclic thermal loads with a cylindrical heater embedded in the sand. The results suggest thermal charging of the surrounding dry sand and natural convection within the wet sand. A comparison of heat transfer for dry, unsaturated and fully saturated sand is presented with graphs and colour maps which provide valuable information and insight of heat and mass transfer around an underground power cable. Furthermore, the measurements of thermal conductivity against density, moisture and temperature are presented showing positive nonlinear dependence. 4950 https://doi.org/10.3390/en14238191$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8:3-2022-00040-3$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00002400 5051 550 5051 600 5051 621.3 5550 convection in porous media 5550 cyclic thermal loading 5550 thermal conductivity 5550 underground power cable 5550 vadose zone heat transfer