Refrigeration

Refrigeration is a process that removes heat from a space, substance, or system to lower and/or maintain its temperature below the ambient one. In other words, refrigeration means artificial (human-made) cooling. Heat is removed from a low-temperature reservoir and transferred to a high-temperature reservoir. The work of heat transport is traditionally driven by mechanical means, but can also be driven by heat, magnetism, electricity, laser, or other means.

History

The concept of refrigeration has been around for many centuries, with evidence of ice and snow being used for cooling as far back as 1000 BC in China. The modern era of refrigeration began in the mid-19th century with the inventions of James Harrison, Alexander Twining, and Jacob Perkins, who developed the first practical refrigeration systems.

Principles

Refrigeration works by exploiting the physical properties of gases. When a gas expands, it absorbs heat, and when it is compressed, it releases heat. This is the principle behind most refrigeration systems.

Applications

Refrigeration has many applications, including, but not limited to, household refrigerators, industrial freezers, cryogenics, and air conditioning. Heat pumps may use the heat output of the refrigeration process, and also may be designed to be reversible, but are otherwise similar to air conditioning units.

Environmental Impact

Refrigeration systems have been identified as a significant source of greenhouse gases due to their use of hydrofluorocarbons (HFCs) as a coolant. Efforts are being made to phase out these substances and replace them with more environmentally friendly alternatives.

See Also

• Air conditioning
• Heat pump
• Thermodynamics
• Greenhouse gases

Refrigeration

• Refrigeration
  Refrigeration
• Ice Harvesting, Massachusetts, early 1850s
  Ice Harvesting, Massachusetts, early 1850s
• William Cullen
  William Cullen
• Appareil Carré
  Appareil Carré
• Early refrigerator car design circa 1870
  Early refrigerator car design circa 1870
• Andrew Muhl Patent
  Andrew Muhl Patent
• SS Dunedin by Frederick Tudgay
  SS Dunedin by Frederick Tudgay
• Early household refrigerator in Popular Science 1919
  Early household refrigerator in Popular Science 1919
• Food into a refrigerator
  Food into a refrigerator
• Refrigeration
  Refrigeration
• Refrigeration
  Refrigeration