All materials will be thicker at higher pressures. Pressures – fluids flow differently at different pressures.Split shell (F Type) designs are good for temperature crosses where the shell and the tube side outlet close the same temperature. For instance, K units are built for boiling the shell side fluid. Different types of shell and tubes work better for different temperature gradients. outlet temperatures – or in other words the amount of heat exchange needed out the unit. As an example, large shell side flows need big shells to distribute their flow without vibrational or pressure drop concerns. The size of your exchanger will be a direct result of the size of your flow rates. Flow Rates – different flow rates require different size exchangers.Below are some highlights of how these different characteristics can affect the design of your heat exchanger. Sizing the correct and most economical exchanger for your application requires a mix of understanding the impacts of site flow conditions and operational needs.
The thermal engineer will design the heat exchanger based on the thermal information you provide, they will then provide an output of the TEMA spec sheet with all of the mechanical information (# of tubes, baffle cut, etc) that is needed to build the exchanger. The image to the right is an example of the standard TEMA data sheet that is often filled out to give the thermal engineer the proper information to size the heat exchanger. These programs will evaluate nozzles flow, thicknesses, etc., and also often provide a starting point for drawings. The mechanical design of your heat exchanger is typically completed with Compress, RCS, ASPEN, and/or other similar programs.
ASPENTech is less conservative than HTRI and is best for single phase applications.
The thermal sizing of your heat exchanger is typically done using HTRI, ASPENtech or other similar software developed/edited by your OEM.