Heat pump and refrigeration cycle. Thermodynamic heat pump cycles or refrigeration cycles are the conceptual and mathematical models for heat pumps and refrigerators.
A heat pump is a machine or device that moves heat from one location (the 'source') at a lower temperature to another location (the 'sink' or 'heat sink') at a higher temperature using mechanical work or a high-temperature heat source. Thus a heat pump may be thought of as a "heater" if the objective is to warm the heat sink (as when warming the inside of a home on a cold day), or a "refrigerator" if the objective is to cool the heat source (as in the normal operation of a freezer).
In either case, the operating principles are identical. Heat is moved from a cold place to a warm place. Thermodynamic cycles Stirling engine. Alpha type Stirling engine.
There are two cylinders. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator. Beta type Stirling engine. There is only one cylinder, hot at one end and cold at the other. Ice. A glacier is made from ice, itself resulting from snow accumulation.
Frozen water in the form of an ordinary (household) ice cube. The white zone in the center is due to tiny air bubbles. Ice is water frozen into a solid state. It can appear transparent or opaque bluish-white color, depending on the presence of impurities such as soil particles or air inclusions. Ice is used for a wide range of applications including cooling, winter sports and the art of ice sculpting. Stirling cycle. This article is about the "adiabatic" Stirling cycle.
For the "idealized" Stirling cycle , see the Stirling engine article. The Stirling cycle is a thermodynamic cycle that describes the general class of Stirling devices. This includes the original Stirling engine that was invented, developed and patented in 1816 by Reverend Dr. Robert Stirling with help from his brother, an engineer.