AFT Blog
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...
The units displayed for the calculated output values can be set by selecting the Options | Unit Preferences menu item. Each property can be selected from the list, and the preferred units applied by selecting the desired unit from the list, and clicking the Set As Preferred Unit button. The units that appear in the list of available units for the input properties can be controlled by checking or unchecking the box next to each unit listed for a property. The selected units can be set as the user's default, so they are used every time the user starts SteamCalc. Multiple...
To calculate the saturated liquid or vapor properties, select the input property as Property #1. Then select either Saturated Liquid or Saturated Vapor as Property#2.
To calculate properties over a range of values, select the Range tab on the main SteamCalc window. This tab allows you to enter a fixed point for the first property, and a range of values for the second property. The calculated values are displayed in the output grid based on an incremental range value that you specify. The values for a range calculation can be plotted graphically by selecting the Options | Create Graph menu item.
To calculate the properties of two points simultaneously, select the Two Points tab on the main SteamCalc window. This tab allows you to enter the property data for two points. The results for both points will be displayed simultaneously. In addition, the difference between the values calculated at each point is displayed in the output.
If you hold down the CTRL key while you drag a junction onto the Workspace and drop onto an existing Workspace junction, the old junction will 'morph' (change) into the new one. Pipes will be connected to the new junction and related data will be copied into the new junction.
To choose only English or SI units for all parameters, select Parameter and Unit Preferences from the Options menu, then select the Unit Preferences tab, choose the Default Unit System and click the Apply Default Units button. This will use will the default units and change the preferred units.