Plate heat design

From the APV heat-transfer handbook—Design Plate Heat Exchangers and J. Marriott s article, Where and How To Use Plate Heat Exchangers, Chemical Engineering, April 5, 1971, there are the following equations for plate heat transfer. 

Plate-type design (space heaters) Type of heat exchanger characterized by a substantial proportion of its heat output being by way of radiant energy. 

Figure 10-7C. The patented COMPABLOG welded plate heat exchanger is technologically advanced, compact, and efficient. The fully welded design (but totally accessible on both sides) combines the best in performance, safety maintenance, and capital/maintenance costs. (Used by permission Vicarb Inc., Canada, publication VNT-3110 1997.)...

Various designs of liquid/liquid heat exchanger are widely used. Choice is partly influenced by the cleanliness of the liquids and the need for regular cleaning. A compact and commonly used type is the plate heat exchanger. 

Higher overall heat transfer coefficients are obtained with the plate heat exchanger compared with a tubular for a similar loss of pressure because the shell side of a tubular exchanger is basically a poor design from a thermal point of view. Considerable pressure drop is used without much benefit in heat transfer efficiency. This is due to the turbulence in the separated region at the rear of the tube. Additionally, large areas of tubes even in a well-designed tubular unit are partially bypassed by liquid and low heat transfer areas are thus created. 

Most plate heat exchanger designs fall into the viscous flow range. Considering only Newtonian fluids since most chemical duties fall into this category, in laminar ducted flow the flow can be said to be one of three types ... 

In the design of the plate heat exchanger, fouling due to coking is of no significance, since the unit cannot be used at such high temperatures. Corrosion is also irrelevant. 

Refrigeration is required for the cold storage rooms and to provide chilled water for the plate heat exchangers. The cellars are very wet areas, and the cooling plant should be designed to maintain as low a humidity as possible, to help preserve the building structure. 

In the laser flash method, the heat is put in by laser flash instead of electric current in the stepwise heating method mentioned above. Thus this method may be classified as a stepwise heating method. A two-layered laser flash method was developed by Tada et al. " The experimental method and the data analysis, including a case involving radiative heat flow, are described in detail in the review article by Waseda and Ohta. A thin metal plate is placed at the surface of a melt. A laser pulse is irradiated onto a metal plate of thickness / having high thermal conductivity. The sample liquid under the metal plate and the inert gas above the plate are designated as the third and first layers, respectively. The temperature of the second layer becomes uniform in a short time" and the response thereafter is expressed by... 

It is not possible to give exact design methods for plate heat exchangers. They are proprietary designs, and will normally be specified in consultation with the manufacturers. Information on the performance of the various patterns of plate used is not generally... 

The transition from laminar to turbulent flow will normally occur at a Reynolds number of 100 to 400, depending on the plate design. With some designs, turbulence can be achieved at very low Reynolds numbers, which makes plate heat exchangers very suitable for use with viscous fluids. 

The trial design should be satisfactory, so a plate heat exchanger could be considered for this duty. 

COOPER, A. and Usher, J. D. (1983) Plate heat exchangers, in Heat Exchanger Design Handbook (Hemisphere Publishing). 

Gasketed plate heat exchangers are commonly used in food processing. What advantages does the design offer in such applications ... 

Plate design, in a reciprocating-plate column, 70 779 Plate diffusers, 26 163 Plate-fin heat exchangers, 73 263 Plate-frame heat exchangers, 73 263 Plate glass, elastic properties, 5 614t Plate heat exchangers, 70 157 73 263-265, 267... 

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