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Inverter Compressor
In air conditioning, an inverter compressor is a compressor that is operated with an inverter. In the hermetic type, it can either be a scroll or reciprocating compressor. This type of compressor uses a drive to control the compressor motor speed to modulate cooling capacity. Capacity modulation is a way to match cooling capacity to cooling demand to application requirements. The first inverter air conditioners were released in 1980–1981. Market needs for variable capacity Many refrigeration and air conditioning systems require reliable processes; The cooling requirements vary over a wide range during the day and over the year due to ambient conditions, occupancy and use, lighting, etc. *In comfort cooling, there may also be the need for a stable and accurate temperature and humidity control in areas such as hospitals, IT & telecoms, process cooling. In applications such as schools, restaurants and office buildings, it is important that the cooling system is able to adapt t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Conditioning
Air conditioning, often abbreviated as A/C (US) or air con (UK), is the process of removing heat from an enclosed space to achieve a more comfortable interior temperature, and in some cases, also controlling the humidity of internal air. Air conditioning can be achieved using a mechanical 'air conditioner' or through other methods, such as passive cooling and ventilative cooling. Air conditioning is a member of a family of systems and techniques that provide Heating, ventilation, and air conditioning, heating, ventilation, and air conditioning (HVAC). Heat pumps are similar in many ways to air conditioners but use a reversing valve, allowing them to both heat and cool an enclosed space. Air conditioners, which typically use vapor-compression refrigeration, range in size from small units used in vehicles or single rooms to massive units that can cool large buildings. Air source heat pumps, which can be used for heating as well as cooling, are becoming increasingly common in cool ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refrigeration
Refrigeration is any of various types of cooling of a space, substance, or system to lower and/or maintain its temperature below the ambient one (while the removed heat is ejected to a place of higher temperature).IIR International Dictionary of Refrigeration, http://dictionary.iifiir.org/search.php ASHRAE Terminology, https://www.ashrae.org/technical-resources/free-resources/ashrae-terminology Refrigeration is an artificial, or human-made, cooling method. Refrigeration refers to the process by which energy, in the form of heat, is removed from a low-temperature medium and transferred to a high-temperature medium. This work of energy transfer is traditionally driven by work (physics), mechanical means (whether ice or electromechanics, electromechanical machines), but it can also be driven by heat, magnetism, electricity, laser cooling, laser, or other means. Refrigeration has many applications, including household refrigerators, industrial freezers, cryogenics, and air conditioni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar-powered Air Conditioning
Solar air conditioning, or "solar-powered air conditioning", refers to any air conditioning (cooling) system that uses solar power. This can be done through passive solar design, solar thermal energy conversion, and photovoltaic conversion (sunlight to electricity). The U.S. Energy Independence and Security Act of 2007 created 2008 through 2012 funding for a new solar air conditioning research and development program, which should develop and demonstrate multiple new technology innovations and mass production economies of scale. History In the late 19th century, the most common fluid for absorption cooling was a solution of ammonia and water. Today, the combination of lithium bromide and water is also in common use. One end of the system of expansion/condensation pipes is heated, and the other end gets cold enough to make ice. Originally, natural gas was used as a heat source in the late 19th century. Today, propane is used in recreational vehicle absorption chiller refrigerator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Handling Unit
An air handler, or air handling unit (often abbreviated to AHU), is a device used to regulate and circulate air as part of a heating, ventilating, and air-conditioning (HVAC) system. An air handler is usually a large metal box containing a Centrifugal fan, blower, furnace or A/C elements, air filter, filter racks or chambers, Sound attenuator, sound attenuators, and damper (architecture), dampers. Air handlers usually connect to a Duct (HVAC), ductwork Ventilation (architecture), ventilation system that distributes the conditioned air through the building and returns it to the AHU, sometimes exhausting air to the atmosphere and bringing in fresh air. Sometimes AHUs discharge (''supply'') and admit (''return'') air directly to and from the space served without ductwork Small air handlers, for local use, are called terminal units, and may only include an air filter, coil, and blower; these simple terminal units are called blower coils or fan coil units. A larger air handler that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Refrigerant Flow
Variable refrigerant flow (VRF), also known as variable refrigerant volume (VRV), is an HVAC technology invented by Daikin, Daikin Industries, Ltd. in 1982. Similar to ductless mini-split systems, VRFs use refrigerant as the primary cooling and heating medium, and are usually less complex than conventional chiller-based systems. This refrigerant is conditioned by one or more condensing units (which may be outdoors or indoors, water or air cooled), and is circulated within the building to multiple indoor units. VRF systems, unlike conventional chiller-based systems, allow for varying degrees of cooling in more specific areas (because there are no large air handlers, only smaller indoor units), may supply hot water in a heat recovery configuration without affecting efficiency, and switch to heating mode (heat pump) during winter without additional equipment, all of which may allow for reduced energy consumption. Also, air handlers and large ducts are not used which can reduce the he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chillers
A chiller is a machine that removes heat from a liquid coolant via a vapor-compression, adsorption refrigeration, or absorption refrigeration cycles. This liquid can then be circulated through a heat exchanger to cool equipment, or another process stream (such as air or process water). As a necessary by-product, refrigeration creates waste heat that must be exhausted to ambience, or for greater efficiency, recovered for heating purposes. Vapor compression chillers may use any of a number of different types of compressors. Most common today are the hermetic scroll, semi-hermetic screw, or centrifugal compressors. The condensing side of the chiller can be either air or water cooled. Even when liquid cooled, the chiller is often cooled by an induced or forced draft cooling tower. Absorption and adsorption chillers require a heat source to function. Chilled water is used to cool and dehumidify air in mid- to large-size commercial, industrial, and institutional facilities. Water c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air-conditioning System
Heating, ventilation, and air conditioning (HVAC ) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation as HVAC&R or HVACR, or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers). HVAC is an important part of residential structures such as single family homes, apartment buildings, hotels, and senior living facilities; medium to large industrial and office buildings such as skyscrapers and hospitals; vehicles such as cars, trains, airplanes, ships and submarines; and in marine environments, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Many compressors can be staged, that is, the gas is compressed several times in steps or stages, to increase discharge pressure. Often, the second stage is physically smaller than the primary stage, to accommodate the already compressed gas without reducing its pressure. Each stage further compresses the gas and increases its pressure and also temperature (if inter cooling between stages is not used). Types Compressors are similar to pumps: both increase the pressure on a fluid (such as a gas) and both can transport the fluid through a pipe (material), pipe. The main distinction is that the focus of a compressor is to change the density or volume of the fluid, which is mostly only achievable on gases. Gases are compressible, while liquids are relatively incompressible, so compressors are rarely used for liquids. The main actio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooling Capacity
Cooling capacity is the measure of a cooling system's ability to remove heat. It is equivalent to the heat supplied to the evaporator/boiler part of the refrigeration cycle and may be called the "rate of refrigeration" or "refrigeration capacity". As the target temperature of the refrigerator approaches ambient temperature, without exceeding it, the refrigeration capacity increases thus increasing the refrigerator's COP. The SI unit is watt (W). Another unit common in non-metric regions or sectors is the ton of refrigeration, which describes the amount of water at freezing temperature that can be frozen in 24 hours, equivalent to or . Formula The basic SI units equation for deriving cooling capacity is of the form: :\dot=\dotC_p\Delta T Where :\dot is the cooling capacity W:\dot is the mass rate g/s:C_p is the specific heat capacity In thermodynamics, the specific heat capacity (symbol ) of a substance is the amount of heat that must be added to one unit of mass of the subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable-frequency Drive
A variable-frequency drive (VFD, or adjustable-frequency drive, adjustable-speed drive, variable-speed drive, AC drive, micro drive, inverter drive, variable voltage variable frequency drive, or drive) is a type of AC motor, AC motor drive (system incorporating a motor) that controls speed and torque by varying the frequency of the input electricity. Depending on its Topology (electrical circuits), topology, it controls the associated voltage or electric current, current variation., quote is per definition on p. 4 of NEMA Standards Publication ICS 7.2-2021. VFDs are used in applications ranging from small appliances to large compressors. Systems using VFDs can be more efficient than hydraulics, hydraulic systems, such as in systems with pumps and damper control for fans. Since the 1980s, power electronics technology has reduced VFD cost and size and has improved performance through advances in semiconductor switching devices, drive topologies, simulation and control techniques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
