This book covers advanced theories and methods in the field of heat and mass transfer, which are expected to improve thermal systems performance and energy efficiency. It reports on novel findings relating to a wide range of topics in industry, building, transportation and agriculture, with a good balance of fundamental and applied research. Based on the best contributions to the 20th International Days on Thermal Science and Energy (JITH 2024), held on 29-31 October, 2024, in Paris, France, this book offers extensive information on the field of thermal science, renewable energies and sustainable energy technologies, addressing an audience of both scientists and professionals.