Thermal building-dynamics example

Four methods for industrial air technology design are presented in this chapter computational fluid dynamics (CFD), thermal building-dynamics simulation, multizone airflow models, and integrated airflow and thermal modeling. In addition to the basic physics of the problem, the methods, purpose, recommended applications, limitations, cost and effort, and examples are pro vided. 

Information about critical points on the PES is useful in building up a picture of what is important in a particular reaction. In some cases, usually thermally activated processes, it may even be enough to describe the mechanism behind a reaction. However, for many real systems dynamical effects will be important, and the MEP may be misleading. This is particularly true in non-adiabatic systems, where quantum mechanical effects play a large role. For example, the spread of energies in an excited wavepacket may mean that the system finds an intersection away from the minimum energy point, and crosses there. It is for this reason that molecular dynamics is also required for a full characterization of the system of interest. 

The two examples, deliberately chosen for their simplicity, show that computational fluid dynamics facilitate a more in-depth examination of the local flow behavior of twin screw extruders. Local peaks in the mechanical and thermal stresses can be easily identified. By changing the geometry, stresses can be reduced and the quality of the polymer can thereby be optimized. Another application focus is the rapid determination of the dimensionless axis intercepts for the pressure build-up A, and A2 and for the power requirement B, and B2. The significance of these parameters has already been discussed in detail in the two previous chapters. 

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