The function of the air cooler is cooling or condensation, which is a kind of heat exchanger. The way of cooling or condensation is heat transfer between the pipe wall or fins and the air outside the pipe. The air is generally provided by the ventilator, but the power consumption is large, and the cooling or condensation effect is easily affected by climate change.
1. Structure of air cooler
The air cooler is mainly composed of tube bundle, ventilator and frame. The tube bundle includes heat transfer pipe, tube box, side beam and beam, etc. It can be arranged in three basic forms: horizontal, vertical and inclined top. The horizontal layout has large heat transfer area, even air distribution and good heat transfer effect. When the inclined roof is arranged, the ventilator is installed in the herringbone central space, which occupies a small area and has a compact structure.
In order to offset the effect of low heat transfer coefficient on the air side, the tubes with finned outer wall are usually used. Finned tube as a heat transfer tube, can expand the heat transfer area. Finned tubes are arranged in layers and the two ends are connected to the tube box by means of welding or expansion joint. The discharge pipe is generally 3-8 rows. The tube bundle series is 12 meters long. The outer diameter of the optical tube is usually 25 mm and 38 mm, the fin height is generally 12-15 mm, the tube bundle width is 100-3000 mm. Finned tube is the core component of air cooler. Its form and material directly affect the equipment performance. Pipes can be made of carbon steel, copper, aluminum and stainless steel. Finned material according to the use of the environment and manufacturing to determine, most of the industrial pure aluminum, in the high requirements for corrosion protection or special conditions of the remanufacturing process also USES copper or stainless steel.
Fins may be arranged horizontally or longitudinally. Finned tube's basic form has: around the piece type, inserts the piece type, the rolled piece type, the welded piece type, the ellipse tube type. The structure of the pipe box mainly includes flange type, pipe plug type and manifold type. Generally, the former is used for middle and low pressure, while the latter two are used for high pressure. In order to adapt to the thermal expansion of the tube bundle, the viewing box at one end is not fixed, allowing displacement along the direction of the tube length.