Heat-transfer options dynamic

Dynamic Heat Transfer Option Figure 3.99 shows the parameters that must be specified when this heat transfer option is selected. The manipulated variable with this option is the flowrate of the cooling water. The temperature of the inlet cooling water is... 

Figure 3.99 Selecting the Dynamic heat transfer option.

However, there are other options for setting up the condenser, which can be used to obtain more realistic models. Figure 8.21 shows that cUcking the drop-down arrow on the right of the Heat transfer option gives several options. The Constant duty option is the default and produces a dynamic model in which condenser heat removal is the manipulated variable. 

The normal distillation models assume instantaneous heat transfer in the condenser and reboiler, and the normal default heat-transfer option is Direct Q. The basic model does not accurately represent the short-term rapid dynamic response under sevCTe conditions because the capacitance (holdup) of material and mass of equipment metal in the reboiler and condenser heat exchangers are not considered. 

To convert a steady-state simulation into a dynamic simulation, the Dynamic button on the top toolbar shown at the top of Figure 3.56 is clicked. If this button is not showing, go to the top toolbar and click View and Toolbars. The window shown at the bottom of Figure 3.56 opens, on which the box in front of Dynamic is clicked. Then the Dynamic item under the reactor block R1 is clicked, which opens the window shown in Figure 3.57. The Heat Transfer page tab lists six possible options that can be used in the dynamic simulation. In our discussion of these alternatives, we will consider the... 

The requirements for the type of equipment are derived from the process duty. They can, however, be met in a variety of ways depending on the physico-chemical properties, the driving forces and the fluid dynamics. At the conceptual level the requirement may be to remove heat. At the next level many options may exist. Thus, heat can be removed by direct contact, by making use of the latent heat of vaporisation or by indirect heat transfer. Each of these more specific duties leads to a range of equipment with their associated properties. No list of equipment will ever be exhaustive as new devices are developed to meet particular needs. Multi-functional equipment in particular may extend the range of applications and thus improve agility. 

The reader is encouraged to repeat this example and choose the movie option to see the temperature profile evolutions dynamically. It should be noted that the rate of evolution of the temperature profile on the screen is not the same as that of the heat transfer process itself. 

Blow moulding softwares take friction between stretched plastic material and mould cavity, and the heat transfer between material / moulds into account. They also allow user to rotate, move and zoom the image dynamically. With this option, contact visualization between mould and material at the end of the simulation can be examined. 

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