About evaporators in chillers, especially falling film evaporator design
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After consulting some information, I found that only Trane's screw chillers use falling film evaporators. That is their patented technology. Can you guys in the HVAC industry give you some advice on the design process or key points?
Falling film evaporators are a bluff! All made from ordinary evaporators~
Falling film evaporator should have some effect in theory, right? Could an expert please give me some advice on what the theory does? Or the principle of action?
When designing, attention should be paid to the distribution of the sprinkler system at the top, and the arrangement of the pipes is different from the general one. There is also the issue of oil return.
Falling film evaporator? This is the first time I've heard of it, what exactly is it? Can anyone explain the principle in detail?
No way? Refrigeration unit evaporator adopts falling film type? Falling film is widely used in evaporation units in the chemical industry, as well as in reboilers of distillation towers. It is mainly used for heat-sensitive material systems. Its advantages are residence time and large heat transfer coefficient. However, the requirements for the installation of the top distributor are high and must be absolutely level.
Can you talk specifically about the oil return problem of falling film evaporators? I am preliminary designing a falling film evaporator, a horizontal tube falling film evaporator.
The falling film evaporator is a relatively advanced evaporator design. Before this design, the most energy-saving and best heat transfer effect was the flooded evaporator design. The refrigerant film in the falling film evaporator evenly covers the heat transfer tubes, absorbing the heat of the medium in the heat transfer tubes. The heat exchange efficiency is very high, the heat transfer temperature difference is small, the refrigeration oil accumulates at the bottom of the evaporator, and is not affected by the refrigerant liquid level, and the oil return is very reliable.
Falling film evaporators can be divided into three types: counter-flow, co-flow, and cross-flow according to the material properties. The operation of the equipment is basically carried out under negative pressure, and the safety performance is good. There are five types: one-effect, two-effect, three-effect, four-effect and five-effect (with steam ejector). The general evaporation capacity is within the range of 1T/h.
For air cooling, just use a humidifying air cooler. Just make sure the fan is running normally, the nozzles are clear, and the water spray atomization effect is good.
The two evaporators are different concepts. The former is used for cooling, and the latter is used for desolvation.