Refrigerators

{{This appliance-related article is a stub.}}

A refrigerator is a common household appliance that consists of a thermally insulated compartment and a heat pump—either mechanical, electronic, or chemical—that transfers heat from the interior of the fridge to its external environment so that the interior is cooled to a temperature below the ambient temperature of the room. Refrigeration is an essential food storage technique in developed countries. The lower temperature lowers the reproduction rate of bacteria, so the refrigerator reduces the rate of spoilage. A refrigerator maintains a temperature a few degrees above the freezing point of water. Optimum temperature range for perishable food storage is 3 to 5 °C (37 to 41 °F).

History

The concept of refrigeration dates back to prehistoric times, when people used ice and snow to store hunting products. The first artificial refrigeration was demonstrated by William Cullen at the University of Glasgow in 1748. However, it was not until 1834 that the first working vapor-compression refrigeration system was built by Jacob Perkins; it was developed further by John Gorrie who built a system for medical purposes.

In 1876, Carl von Linde patented the process of liquefying gas that has become the principal method for low-temperature refrigeration. By the early 20th century, the invention of domestic refrigerators had become widespread in homes.

Design

Modern refrigerators generally make use of the vapor-compression cycle, which uses the evaporation of a refrigerant to provide cooling. The components of a refrigerator include:

• Compressor: The compressor is the "heart" of the refrigerator cycle. It pumps the refrigerant through the system.
• Heat-exchanging pipes (serpentine or grid-like coils of tubing behind or under the unit in which the refrigerant flows and evaporates)
• Expansion valve or capillary tube: A device that reduces the pressure of the liquid refrigerant thereby cooling it.
• Evaporator: A set of coils inside the refrigerator where the refrigerant absorbs heat and vaporizes, cooling the inside of the refrigerator.

Types of Refrigerators

Refrigerators come in various sizes and designs to suit different needs:

• Top freezer refrigerators have the freezer compartment situated above the refrigerator compartment.
• Bottom freezer refrigerators have the freezer compartment located below the refrigerator compartment.
• Side-by-side refrigerators feature two doors that open outward with the freezer on one side and the refrigerator on the other.
• French door refrigerators combine the features of side-by-side and bottom freezer models, with a two-door refrigerator on top and a freezer drawer below.
• Compact refrigerators are smaller and typically used in places like dorm rooms or offices.

Impact on Society

The refrigerator has had a profound impact on society. Before its invention, preserving food was a constant challenge, leading to significant food waste. With the advent of refrigeration, it became possible to store food for longer periods, reducing waste and improving the safety of food consumption.

Environmental Considerations

Refrigerators have environmental impacts, including the use of refrigerants that can contribute to ozone depletion and global warming. Modern refrigerators tend to use more environmentally friendly refrigerants and are designed to be more energy-efficient.

Future Developments

The future of refrigeration may include innovations such as magnetic refrigeration, which uses the magnetocaloric effect to provide cooling. This technology promises higher efficiency and less environmental impact.

This appliance related article is a stub. You can help WikiMD by expanding it.