This book puts forward 7 basic principles and 3 principle systems in terms of "thermal physics": the atmospheric pressure follows work principle system; the work-heat confrontation principle system; the gas has density internal energy and the density internal energy can be directly converted into thermal internal energy during expansion. More than 60 relations and equations belonging to these three principle systems are introduced, and these relations and equations are integrated into relevant thermodynamic calculations. This book can be read by experts, scholars, university teachers and students, and interested readers who are familiar with "Basics of Thermal Engineering".
