Setting time parameters
See also Automatic Time Step Size Calculation in Transient Analysis
With problems of transient analysis type, you need to set up the time parameters, before the problem can be solved. To do so, click Timing tab in the problem description dialog box.
Calculate up to:
Specify the period of time you wish to simulate. Simulation always starts at "zero" time moment.
With the step of:
Specify the step size for the calculation. In transient analysis, this is the most important parameter controlling the precision of calculations in time domain: the smaller the step, the better the precision. Usually you will have minimum of 15 to 20 steps for the whole integration period. It may have sense to start with bigger value of this parameter and then decrease it if the result seems to change not smoothly enough.
If for some model you cannot estimate suitable time parameters, we recommend that you set some arbitrary value for the time period, and set the step size to have 5-7 points of integration, and then explore the X-Y plots against time in several points in the domain to tune the parameters.
Store the results every:
defines the time increment for saving the results of calculation to the file. This value must be equal or greater than the step size.
Starting from the moment:
defines the first point to be written to the file. If this value is zero, the initial state will be written.
Enter the temperature value for the initial (zero) moment of time. Temperature may be defined as a constant or coordinate-dependent formula. If the initial temperature is not defined, it is considered zero. If the initial temperature value (formula) is set and also the coupled problem provides the initial temperature distribution then the imported temperature has a priority.