Plate fin heat recovery
advantage
(1) The heat transfer efficiency is high, because the disturbance of fins to the fluid makes the boundary layer break continuously, so it has a large heat transfer coefficient; at the same time, because the clapboard and fins are very thin and have high thermal conductivity, so the plate fin heat exchanger can achieve a high efficiency.
(2) Compact, because of its extended secondary surface, the specific surface area of the plate fin heat exchanger can reach 1000 ㎡ / m3.
(3) It is light and compact, mostly made of aluminum alloy. Now steel, copper and composite materials have been produced in batches.
(4) The plate fin heat exchanger can be applied to the heat transfer among gas, gas-liquid, liquid-liquid, various fluids and the phase change heat transfer with the change of set state. The arrangement and combination of the flow passage can adapt to different heat exchange conditions, such as countercurrent, cross flow, multi stream and multi pass flow. Through the combination of series connection, parallel connection and series parallel connection, the heat exchange needs of large equipment can be satisfied. In industry, it can be finalized and mass produced to reduce cost and expand interchangeability through building block combination.
(5) The manufacturing process is strict and complex.
(6) It is easy to block, not resistant to corrosion, and difficult to clean and repair, so it can only be used in the situation where the heat exchange medium is clean, free of corrosion, not easy to scale, not easy to deposit and not easy to block.
working principle:
In terms of heat transfer mechanism, plate fin heat exchanger still belongs to shoulder arm heat exchanger. Its main feature is that it has an extended secondary heat transfer surface (fins), so the heat transfer process is not only on the primary heat transfer surface (partition), but also on the secondary heat transfer surface. In addition to the primary surface pouring into the low-temperature side medium, the heat of the high-temperature side medium also transfers part of the heat along the height direction of the fin surface, that is, along the height direction of the fin, the heat is poured into the partition plate, and then the heat convection is transferred to the low-temperature side medium. Because the fin height is much larger than the fin thickness, the heat conduction process along the fin height direction is similar to that of the homogeneous slender guide rod. At this point, the thermal resistance of the fins cannot be ignored. The highest temperature at both ends of the fin is equal to the temperature of the baffle plate. With the convection and heat release of the fin and the medium, the temperature decreases until the medium temperature in the middle of the fin.
Application:
Plate fin heat exchanger has been more and more widely used in various industrial sectors due to its superior performance and mature technology.
1. Air separation equipment: the main heat exchanger, subcooler, condensing evaporator and other low-temperature heat exchanger of air separation equipment can save equipment investment and installation cost and reduce unit energy consumption after adopting plate fin heat exchanger.
2. Petrochemical Industry: plate fin heat exchanger has the advantages of large capacity, good separation effect and low energy consumption. It has been used in the process of ethylene cryogenic separation, ammonia nitrogen washing, natural gas, oil field gas separation and liquefaction.
3. Construction machinery: after more than 20 years of research and practice, many countries in the world have produced and used plate fin heat exchanger in batches on automobile, locomotive radiator, digging oil cooler, refrigerator radiator and high-power transformer radiator.
4. Superconductivity and space technology: the development of low temperature superconductivity and space technology provides a new way for the application of plate fin heat exchanger, which has been applied to Apollo spacecraft in the United States and Shenzhou spacecraft in China
