Explore an alternative to brazed plate units.



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Micro plate heat exchanger technology helps ensure energy efficiency in chiller applications.


 

Increasing demands for efficiency and sustainable development have driven the development of a new technology, the micro plate heat exchanger (MPHE).

Features of micro plate heat exchanger technology include improved energy efficiency, improved heat transfer, reduced use of raw materials and minimal holdup volumes, all of which bring economic and environmental benefits.

The dimple technology is the main driver behind the micro plate heat exchanger’s high efficiency, offering improved heat transfer over traditional designs due to the more uniform flow around the brazing points.

  • Laboratory tests by one heat exchanger maker show that the difference between the maximum and minimum velocities in a micro plate heat exchanger is one-third of the ratio in a brazed plate heat exchanger.
  • The micro plate heat exchanger achieves a balance between increased turbulence and frictional losses, increasing the heat transfer coefficient and improving efficiency, according to the tests.
  • Brazed plate heat exchangers have brazing points in fixed, regular locations across the plates.
  • In the micro plate heat exchanger, the position of each brazing point can be determined individually; this means brazing points can be concentrated in areas subject to higher mechanical forces.
  • Strength is further increased by the dimples themselves, which offer a greater contact area.

The ability to position brazing points where needed also allows designers to select patterns to suit different applications. One manufacturer offers micro plate heat exchangers in dedicated models for chiller and heat pump applications.



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Micro plate heat exchangers are used in heat pump and chiller applications.

Opportunities for Chillers and Heat Pumps

Micro plate heat exchanger technology may help users penetrate new markets and deliver greater savings. Although the technology is universal across applications, early adopters have been concentrated in the heat pump and chiller segments. The efficiency gains from using micro plate heat exchangers in heat pumps are enabling manufacturers to increase profits and market share. In the chiller industry, which uses larger units, the micro plate heat exchangers enable solutions for both single- and dual-circuit systems.

One manufacturer's micro plate heat exchanger has a lower holdup volume compared with brazed plate heat exchangers. The heat exchanger also is smaller, reducing the refrigerant charge by up to 40 percent. This represents a savings on the initial refrigerant charge, but the need for refills also impacts running costs. For a typical heat pump (60 kW), the savings on refrigerant can be significant.

Likewise, the price of raw materials directly affects the price of heat exchangers. The micro plate heat exchanger technology requires fewer raw materials. So, for a given capacity, a lighter unit can be used.



Laboratory tests show that the difference between the maximum and minimum velocities in a micro plate heat exchanger is one-third of the ratio in a brazed plate heat exchanger.


Asymmetrical Flows

Micro plate heat exchanger’s dimple technology allows design flexibility to exploit asymmetrical flows. Micro plate heat exchangers can achieve asymmetry ratios

Micro plate heat exchanger’s dimple technology allows design flexibility to exploit asymmetrical flows.

as high as 1:27, which allows the asymmetrical flow to be adapted precisely to the given operating conditions.

Establishing the exact relationship between the two fluids in the heat exchanger is critical to creating asymmetrical solutions. Micro plate heat exchanger technology offers high flexibility within its asymmetric envelope, making it possible to design correct asymmetric flows for a given application and operating conditions. The efficiency of micro plate heat exchanger with asymmetric flows has been verified in laboratory tests, and customer field tests show efficiency increases with the technology.Micro plate heat exchanger technology is a disparate yet safe choice. The units are manufactured in the same way as traditional brazed plate heat exchangers, following a proven manufacturing process. In addition, the same pressure vessel codes apply. PC