The high head loss is due to water moving through a small titanium tube that is also spiraled.
In my opinion, they need to double the diameter of the titanium tube to provide better hydraulic efficiency.
Water flows through the inner tube and refrigeration flows between the outer & inner tube (refrigeration loop).
The temperature of refrigeration and water are different, so heat will transfer from one with high temperature to the other one.
The flow is mostly counter-flow.
If you have 100 lbs of water that has a 10 degree temp increase, that is 1,000 btu transferred.
Water In = 80 and water out = 90 degrees.
If you have 50 lb of water that has a 19 degree temp increase, then that is 950 btu transferred.
Water In = 80 and water out = 99 degrees.
People focus on the temp increase when they need to focus on the btu (heat) transferred.
What is a coaxial heat exchanger? A coaxial heat exchanger is a kind kind of tube heat exchanger, it is usually used as condenser or ev...
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The coaxial heat exchanger is designed as a "tube in tube" structure.
Usually the outer tube is made of steel/copper, and the inner tube can be titanium, copper, copper-nickel depending on the requirements of working condition.
For the inner tube is has many spiral grooves on the surface, which will enlarge the connection surface and get more heat transferred.
A coaxial heat exchanger operates using a concentric tube design, with one tube fitting inside the other. The two tubes are separated by an air gap or filled with insulation to prevent heat transfer between them.
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A pool heat pump heat exchanger distributes harvested heat, but exactly how it does that is what we explain in this post
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Coaxial coils are fairly simple in their construction.
The outside of the coil carries refrigerant, while the inside handles the water.
These coils are designed to counterflow the two mediums to exchange heat rapidly.
The inside of the coil is also rifled, creating a swirling effect that helps this process go further (see the diagram below).
A quick and simple guide to the basics of operation, method of heat exchange, and safety features found in air-to-water pool heat pumps.
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