What is a Heat Exchanger?
A heat exchanger is a specialized device that assists in the transfer of heat from one fluid to the other. In some cases, a solid wall may separate the fluids and prevent them from mixing. In other designs, the fluids may be in direct contact with each other. In the most efficient heat exchangers, the surface area of the wall between the fluids is maximized while simultaneously minimizing the fluid flow resistance. Fins or corrugations are sometimes used with the wall in order to increase the surface area and to induce turbulence. Common appliances containing a heat exchanger include air conditioners, refrigerators, and space heaters. Heat exchangers are also used in chemical processing and power production. Perhaps the most commonly known heat exchanger is a car radiator, which cools the hot radiator fluid by taking advantage of airflow over the surface of the radiator. There are three primary flow arrangements with heat exchangers: counter-flow, parallel-flow, and cross-flow. In the
A Heat Exchanger is a device built for the efficient transfer of heat from one medium to another, whether the media are separated from each other, so they do not mix, or the media are in direct contact. Where are Heat Exchangers used? Heat Exchangers are widely used in space heating, water heating, refrigeration, air conditioning, power plants, chemical plants, petrochemical plants, sugar refineries, petroleum refineries, natural gas processing, industrial machinery and even motorized vehicles. What is a Brazed Plate Heat Exchanger? A Brazed Plate Heat Exchanger is a type of heat exchanger that because of its design, allows for a very compact-sized unit with the ultra-efficient transfer of heat from one fluid to another fluid, without the two fluids mixing. The design of Brazed Plate Heat Exchangers calls for the use of thin layers of stamped stainless steel plates. The stamping pattern of the stainless steel plates creates baffles which become channels for two separate fluids to run t
For heating coils, hot water and steam are the most common, and this heated fluid is supplied by boilers, for example. For cooling coils, chilled water and refrigerant are most common. Chilled water is supplied from a chiller that is potentially located very far away, but refrigerant must come from a nearby condensing unit. When a refrigerant is used, the cooling coil is the evaporator in the vapor-compression refrigeration cycle. HVAC coils that use this direct-expansion of refrigerants are commonly called DX coils. On the air side of HVAC coils a significant difference exists between those used for heating, and those for cooling. Due to psychrometrics, air that is cooled often has moisture condensing out of it, except with extremely dry air flows. Heating some air increases that airflow’s capacity to hold water. So heating coils need not consider moisture condensation on their air-side, but cooling coils must be adequately designed and selected to handle their particular latent (mois
The purpose of this article to learn the fundamental difference between a single-boiler and a heat exchanger found on the insides of espresso machines. Let’s start with a single-boiler, home model espresso machine. These boilers typically have thermostats that regulate the temperature. There is one thermostat for coffee mode, and another thermostat for steam mode. The same water in the boiler is utilized for espresso extraction and for steam production. As the operator of the machine turns on a single boiler espresso machine, the machine is set to reach a certain temperature for coffee. When the steam button is depressed, the steam thermostat is engaged to allow the boiler to go to a higher temperature so that steam is produced. Typically, the same boiler space and same heating element is used for both coffee and steam modes. However, some machines, like the La Pavoni Europiccola have two heating elements inside the same boiler – one for coffee and one for steam.
A heat exchanger is a device designed to efficiently transfer or “exchange” heat from one matter to another. When a fluid is used to transfer heat, the fluid could be a liquid, such as water or oil, or could be moving air. The most well known type of heat exchanger is a car radiator. In a radiator, a solution of water and ethylene glycol, also known as antifreeze, transfers heat from the engine to the radiator and then from the radiator to the ambient air flowing through it. This process helps to keep a car’s engine from overheating. Similarly, Lytron’s heat exchangers are designed to remove excess heat from aircraft engines, optics, x-ray tubes, lasers, power supplies, military equipment, and many other types of equipment that require cooling beyond what air-cooled heat sinks can provide.
