Boundary Conditions window
The window Boundary Conditions enlists all spaces of which the user sets temperatures and all power sources of which power density can be entered (the boundary conditions). For dynamic, transient problem solution the window mutates to allow input of time dependant quantities.
Temperatures of spaces are initially preset to standard values:
Remark: These standard values can be changed within application settings.
Spaces are enlisted alphabetically. Knowing this, by consequently naming spaces you can target proper automatic assignment of preset values.:
If the component contains power sources (heat sources or sinks) also, their names will be offered here for the input of their respective power density [W/m3]. Initially power sources are set to have no power (equal 0 W/m3).
Remark: If there is solution of vapour calculation available too, the input of relative humidity of air space, required for vapour evaluations of partial pressure, is also offered in additional dedicated column:
Relative humidity of air spaces is initially preset as follows:
Remark: These standard values can be changed within
You confirm the data entered by pressing the button Apply. Boundary conditions will be applied onto basic solutions (g-values). If calculation of basic solutions is also required it will be automatically initiated also.
Remark: The button "Apply" will blink if there is new
solution set available from the
solver, but the data entered in this window has not been applied yet to
the new solution set.
The temperature distribution with the construction results from the
superposition of respective basic solutions each multiplied by its boundary
condition. Results are presented as
text reports ready for
printing or to be saved as Adobe PDF, MS.Word
or MS-Excel files.
Templates of Boundary conditions are saved to the project file when the project is saved.
Remark: All BCs will be merged by their Names into the projects BC-Template upon apply. This will retain BCs even when spaces or power source are renamed or removed from the project. By that the BCs of other projects can be merged and saved - even such with names which are not yet (or no more) available if the current project.
Important: To retain the values of boundary conditions between program executions the project must be explicitly saved (project data is not saved automatically when boundary conditions are applied!).
Remark: You will need the value of power density W/m3 to properly enter the boundary condition specific to power sources. For verification purposes you will find the total volume of each power source within Modelling Report. Within Results Report, in addition to the value of respective power densities, you will also find the overall power of each power source.
Transient Boundary Conditions (periodic, harmonic)
For the purpose of dynamic, transient problem (subject to the TRANSIENT-Option) the boundary conditions window mutates to input of time dependant quantities.
The transient boundary conditions are provided as sets of harmonic Fourier coefficients created for respective periodic data (these are managed in Periodic / Harmonic Data Editor) for each and any Main Period of the transient problem (as selected in Solver parameter form).
Boundary conditions are kept distinct of each solution period and also saved to the project file when the project is saved. Important: To retain the values of boundary conditions lately applied the project must be explicitly saved (project data is not saved automatically when boundary conditions are applied!).
Remark: All BCs will be merged for each Period (including MainPeriod=0 - steady state) by their Names into the projects BC-Template upon apply. This will retain BCs even when spaces or power source are renamed or removed from the project. By that the BCs of other projects can be merged and saved - even such with periods and names which are not yet (or no more) available if the current project.
Time Point to Evaluate: provided existence of periodic boundary conditions on can set the evaluation time point (within the main period)
For the evaluation the harmonic base solutions are combined with the respective harmonic coefficients of the boundary condition the belong to (complex linear combination). The resulting distribution harmonic coefficients it then passed for Fourier synthesis for specific evaluation time point T.
Remark: Provided that the periodic boundary conditions did not change, only synthesis for new time point must be executed.
Remark: Evaluating in TRANSIENT mode with only 0-th harmonic or only Constant Boundary Conditions is identical to Steady State results (regardless of HARMONIC or TRANSIENT license feature).
Remark: The input of relative air humidity (when vapour diffusion problem has been solved too) are sill constant (steady state) and independent of air temperatures. Only the partial pressure will be recalculated for respective, evaluation time point dependant, air temperature.