AFT Blog

The areas on the Specification Window which are required can be highlighted by either pressing the F2 key or by double-clicking on a blank area somewhere on the Specification Window.

To check the properties of the objects connected to the one you are specifying, position the mouse pointer on the connected object's ID (listed in the specification window) and hold down the right mouse button.

The inspection feature saves time by displaying the properties of a Workspace object in a read-only fashion. To inspect an object, position the mouse pointer on the object and hold down the right mouse button.

Very large and complex models may be constructed by building smaller models and merging them together. It is a good idea to break the large system into logical parts where there are known boundary conditions (flowrates or pressures).

Flow direction arrows are for reference only, the actual direction being determined by the analysis and, if the direction is opposite the reference direction you've specified, values for flow, velocity and pressure drop will be negative. If you don't want negative values, simply select the pipe, press F3 to toggle the direction arrow and rerun your model. While this is fine for one or a few pipes, what if you have many pipes with negative flow values? Within the Workspace, open Select Special (on the Edit menu or by pressing F6). For 'Selection Type', select 'Pipe Output Properties', then 'Volumetric Flow...

Using “Specified Heat Rate In Constants” for the thermal model of heat exchangers can often cause problems in system models.  The reason why is because this thermal model type causes the heat exchanger to act like an “assigned heat input” junction as does an assigned flow junction does for providing constant flow rates.  Another problem is that this thermal model can cause unrealistic temperature changes across a heat exchanger.  When the heat rate is specified and the mass flow rate and heat capacity are calculated based on the system solution, the temperature change will be whatever is required to maintain the...