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Thermal Design
Plate heat exchangers : A deeper look into thermal design
Heat exchangers are some of the most common equipment types in industry . Their range of application is quite wide , spanning from marine environments and chemical processes to energy , power plants , refineries and more . The design period of a heat exchanger takes into account thermal and mechanical calculations and pre-manufacturing periods . To build on existing general knowledge about the thermal side of design , manufacturers need to be more considerate of other parameters .
By Enes Kuzey Er - R & D Specialist , Ekin Endustriyel Heat exchanger working principle
About the author
Enes Kuzey Er is the Heat Transfer Product Sales - R & D Specialist for Ekin Endustriyel , responsible for sales of heat transfer products such as plate type heat exchangers ( gasketed or brazed ) and shell and tube heat exchangers . He is also researching solutions for industry needs through customer feedback , and provides support for related research and development processes .
Beyond technical data sheets To design a heat exchanger , the designer needs to make sure that the required heat transfer between two streams will be achieved . The starting point of a heat exchanger design is the first law of thermodynamics . After determination of the capacity , the heat transfer formula below is applied to have overall heat transfer coefficient ( Uo ). * Qr = m × cp × �T * Qc = Aeff × U 0
× LMTD
It is clear that the main goal of a design process is to have an acceptable heat transfer rate and pressure loss . Yet there are more factors that need to be considered . Let ' s take a look at one of the most common types of heat exchangers : Plate type heat exchangers .
Turbulence The heat transfer rate is directly effected by the type of flow . Turbulence causes better heat transfer beside laminar flow . To have turbulence in the channels of a plate heat exchanger , the Reynolds number must be more than 2200 . The Reynolds number is a function of velocity occuring in the channels . A fewer number of channels means higher level of turbulence yet also higher pressure losses . So , the balance between these parameters is important .
Laminar Flow
Turbulent Flow
Flow regimes
Exploded view of a standard plate type heat exchanger . www . heat-exchanger-world . com Heat Exchanger World September 2023
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