AC
Alfa Laval maiņstrāvas līnija ar lokaniem plātņu siltummaiņiem nodrošina efektīvu siltuma pārvadi ar nelielu pēdas nospiedumu. Tie ir īpaši izstrādāti darbam gaisa kondicionēšanas, saldēšanas, dzesētāju un siltumsūkņu vajadzībām.
Cietās plātnes siltummaiņus plaši izmanto saldēšanas iekārtās. Tos parasti izmanto, lai pārvadītu siltumu no aukstumaģenta – primārā šķidruma – un no ūdens vai sāls kā sekundāro šķidrumu.
Alt Laval maiņstrāvas līnijas blokus ar vara kausētiem siltummaiņiem galvenokārt izmanto kā:
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Iztvaicētāji sausai izplešanai un dzesēšanas ūdenim
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Kondensatori siltuma atgrūšanai vai reģenerācijai ūdenī
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Ekonomizatori dzesēšanas šķidruma dzesēšanai un dzesēšanas reaģenti ar superapkures tvaiku.
Tos var izmantot arī kā:
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Apakšdzesētāji šķidro dzesētāju dzesēšanai, izmantojot labi ūdeni
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Vidējie siltummaiņi absorbcijas ciklā, lai uzsildītu atšķaidīto šķīdumu vai pirms tam atdzesētu koncentrēto šķīdumu.
Darbības pamatprincipi
Brazed plate heat exchangers used for HVAC applications normally use a parallel flow to achieve the most efficient heat transfer. In a single-pass design, all the connections are located on one side of the heat exchanger, making installation very easy.
Alternate channel pattern
When used as an evaporator, the channels formed between the corrugated plates and corners are arranged so the two media flow through alternate channels, always in opposite directions (counter-current flow). The two-phase refrigerant (vapour + liquid) enters at the bottom left of the unit. The vapour quality depends on operating conditions in the refrigeration plant.
Dry expansion
Evaporation of the liquid phase takes place inside the channels. Some degree of superheating is always required – hence the process being called "dry expansion". The dark blue and light blue arrows show the location of the refrigerant connections. The water (brine) to be cooled flows counter-currently in the opposite channel; the dark and light red arrows show where the water (brine) connections are.
AC line as condenser
When used as a condenser, the main components are still the same as for the evaporator. The refrigerant enters at the top left as a hot gas and starts to condense on the surface of the channels. Once fully condensed, it is then subcooled slightly, in a process called "free condensation". The dark and light blue arrows show the location of the brine connections. The refrigerant flows counter-currently in the opposite channel and is cooled. The dark and light red arrows show where the refrigerant connections are.