Search results
Results From The WOW.Com Content Network
The Carnot cycle, which has a quantum equivalent, [11] is reversible so the four processes that comprise it, two isothermal and two isentropic, can also be reversed. When a Carnot cycle runs in reverse, it is called a reverse Carnot cycle. A refrigerator or heat pump that acts according to the reversed Carnot cycle is called a Carnot ...
A Carnot cycle is an ideal thermodynamic cycle proposed by French physicist Sadi Carnot in 1824 and expanded upon by others in the 1830s and 1840s. By Carnot's theorem, it provides an upper limit on the efficiency of any classical thermodynamic engine during the conversion of heat into work, or conversely, the efficiency of a refrigeration system in creating a temperature difference through ...
Nevertheless, the Carnot cycle demonstrates that the state of the surroundings may change in a reversible process as the system returns to its initial state. Reversible processes define the boundaries of how efficient heat engines can be in thermodynamics and engineering: a reversible process is one where the machine has maximum efficiency (see ...
The ionocaloric refrigeration cycle is an advanced cooling technology that utilizes the ionocaloric effect, driven by an electrochemical field, to achieve efficient and eco-friendly refrigeration. By manipulating the electrochemical potential through ion addition or removal, significant temperature changes and entropy variations are achieved.
The operating principle of the refrigeration cycle was described mathematically by Sadi Carnot in 1824 as a heat engine. The most common types of refrigeration systems use the reverse-Rankine vapor-compression refrigeration cycle, although absorption heat pumps are used in a minority of applications. Cyclic refrigeration can be classified as:
Common absorption refrigerators use a refrigerant with a very low boiling point (less than −18 °C (0 °F)) just like compressor refrigerators.Compression refrigerators typically use an HCFC or HFC, while absorption refrigerators typically use ammonia or water and need at least a second fluid able to absorb the coolant, the absorbent, respectively water (for ammonia) or brine (for water).
The Cromer cycle is primarily used in air conditioning and drying applications. The cold surface portion of the cycle is most often a result of a reversed Carnot or refrigeration cycle. For the Cromer cycle to operate, a desiccant must be exposed to two air streams, one with higher humidity from a cold surface, and one with lower humidity to ...
The most common refrigeration cycle is the vapor compression cycle, which models systems using refrigerants that change phase. The absorption refrigeration cycle is an alternative that absorbs the refrigerant in a liquid solution rather than evaporating it. Gas refrigeration cycles include the reversed Brayton cycle and the Hampson–Linde cycle.