You can choose the model on the Parameters page of the Rating tab. Once the Dynamic Rating model is selected, no further information is required on the Parameters page of the Design tab. Any rating information entered using these models is observed in Dynamic mode. The Basic, Intermediate, and Detailed Dynamic Rating models share rating information with the Dynamics Heat Exchanger model. In the detailed model, detailed geometry is required to rate the heat exchanger. If the zonal analysis and tube thermal inertia are required without providing the detailed geometry the intermediate model can rate the heat exchanger. If two/three temperatures and overall transfer coefficient is available, then the exchanger can be rated with the Basic Model. There are three models available for the Dynamic Rating Due to the solver method incorporated into this rating model, the Steady State Rating model can perform calculations exceptionally faster than the Dynamic Rating model. The assumption of this model is the same as the simple endpoint restated below:Įxchanger rating calculation can be performed if the detailed geometry is known. This model is the extension of the Simple End Point Model to incorporate the rating calculation of the heat exchanger.
Note: This model is available only for counter-current exchangers. Overall exchanger UA can be calculated by adding the UA of each interval. The LMTD and overall heat transfer coefficient are calculated for each internal. In this model, the heating curves are broken into intervals (default intervals are 5) and energy balance is performed on each internal. The phase change of pure components in one or both Heat Exchanger sides.When the assumptions of the Simple End Point Model are not valid then the Simple weighted model can be used instead. Heat curves for both Heat Exchanger sides as linear.The Simple End Point Heat Exchanger model is based on the same equation as shown above. Specific heats of both shell and tube side streams remain constant.The overall heat transfer coefficient is constant.There are two main assumptions of this model: