Course: Thermodynamics in Energy Engineering

Perpetual motion machine of the second kind  Perpetual motion machine of the second kind is a machine which produces work from a single heat source. In this kind of perpetual …

In the spring-gas system before An ideal gas is contained in a cylinder. Initially the pressure, volume and temperature were P1, V1, and T1. A spring with a spring constant …

We know that the freezing of water at meting point is a reversible process. Calculation of entropy for the system (the water) and surrounding for this freezing process is simply …

Intuitively, we know that the freezing of water below meting point, e.g -10 ℃ occurs spontaneously. It means freezing of supercooled water is a irreversible process. Calculation of the entropy …

We can calculate the entropy changes between two states of different temperature if we know the heat capacities. When the pressure is constant, integration of Cp over temperature with respect …

The entropy change for a chemical reaction among pure, crystalline substances is zero at the absolute zero K by the Third law of thermodynamics. Therefore, the entropy change of a …

We can express the entropy as a function of temperature and volume. It can be derived from the combination of the first and the second law for the closed system. …

The third law is talking about the entropy of pure, perfectly crystalline materials at zero K. They have zero entropy at zero K, by the third law. Therefore, in classical …

We cannot reach absolute zero temperature. By the 3rd law, entropy is zero, at zero K. If we think about what the temperature is, it is a measure of internal, …

Heat pump vs resistive heating Which one is efficient? In the resistive heating, W = RI2 = Q when there is no loss. The maximum efficiency of resistive heating is …

This week, you learned the second law of thermodynamics. The second law is the entropy principle. The second law is concerned with the conversion of heat into work and the …

Welcome to the 4th week of the course.During this week, we are still talking about the second law of thermodynamics, but we are going be looking at its application to …

Heat engine is a system that convert thermal energy into mechanical energy. It is a traditional energy conversion system. Steam engine, internal combustion engine, and gasoline engine belong to the …

We have represented the heat engine cycle on a T-S diagram. Here we can express it on P-V diagram. At the high temperature source, the boiler, the fluid experience isothermal …

Refrigerator and heat pump extract heat from the low temperature side, release heat to the high temperature side by doing work on the machine. Depending on the purpose of the …