Solution dialog box — Initial Conditions

Option	Analysis/Solution Type	Description
Initial Conditions	Flow****Coupled Thermal-Flow	Controls how the initial values of all thermal and flow quantities in the model are defined.AutomaticSets default uniform initial values.UniformSets specified uniform initial values. Use this option to set initial condition values for humidity, mixtures, and water content.From Results in Other DirectorySets the initial condition values to results from a previous solve. Select the file and directory location in the File/Directory Selection group and the Initial Condition Selection group.Note: Make sure that the necessary files that you want to use from a Simcenter 3D Multiphysics coupled analysis are not in a zipped folder. The software does not automatically unzip the folder.**From File (TEMPF format)**Sets the initial temperature to the values in the TEMPF solver file. This option is available only in the Initial Temperature list.Perform Steady-State SolutionAvailable when Analysis Type is set to Thermal.Instructs the solver to first perform a steady state analysis of the model, then immediately launch the transient analysis, using the steady state value obtained as the initial condition.
Initial Temperature	Thermal
Thermal
Appears when Initial Conditions or Initial Temperature are set to Uniform.
Temperature Value	Thermal****Coupled Thermal-Flow	Sets the initial temperature value for the solid model.
3D Flow
Appears when Initial Conditions is set to Uniform.
X VelocityY VelocityZ Velocity	Flow****Coupled Thermal-Flow	Set the initial velocity component values for the fluid in the model.
Pressure	Sets the initial pressure value for the fluid in the model.
Fluid Temperature	Sets the initial temperature value for the fluid in the model.
Turbulence
Appears when Initial Conditions is set to Uniform.
Turbulence Characteristics	Flow****Coupled Thermal-Flow	Specifies the calculation method for initial turbulence quantities in the flow based on available data derived from experiment or standard references.AutomaticComputes turbulence characteristics using default values.Turbulence Characteristics modeling objectLets you specify the method for calculating initial turbulence quantities through the selected Turbulence Characteristics modeling object.You can also select a previously defined Turbulence Characteristics modeling object from the list or click Create Modeling Object to define a new modeling object.Click Edit to modify the specified modeling object.For more information, see Turbulence Characteristics.
Humidity, Tracer Fluids, and Mixtures
Appears when Initial Conditions is set to Uniform.
Humidity	Flow****Coupled Thermal-Flow	Specifies the initial conditions for humidity.NoneIndicates that the initial humidity content in the fluid domain is not set.RelativeCalculates the fluid humidity using the Relative Humidity (%) value that you set.SpecificCalculates the fluid humidity using the Water Vapor to Dry Air Mass Ratio value that you set.
Tracer Fluid	Advanced FlowAdvanced Thermal-FlowAdvanced Thermal-Flow with ESC	Specifies the initial conditions for mass fractions for the tracer fluids.NoneIndicates that the initial mass fraction values for the tracer fluids are not set.Specify FractionsLets you set the initial conditions for mass fractions for the tracer fluids. You must first use the Tracer Fluid List option to either select or create the Tracer Fluid modeling objects for which you want to specify initial mass fraction values. Then use the Tracer Fluid Mass Fractions option to set the initial mass fractions for the specified Tracer Fluid modeling objects.As a good practice, enter values from 0 to 1 for each mass fraction. The percentage of the main fluid is calculated as 1–∑Mass Fractions.If the sum of the mass fractions you enter is greater than 1, the values are normalized.You can use Cut , Copy , and Paste commands to enter the mass fraction values.
Mixture	Advanced FlowAdvanced Thermal-FlowAdvanced Thermal-Flow with ESC	Specifies the initial mass fractions for the components of the homogenous fluid mixture.NoneIndicates that the initial mass fractions for the homogenous mixture components are not set.Specify FractionsLets you set the initial mass fractions for the homogenous mixture components using the Mixture Mass Fractions option.As a good practice, enter values from 0 to 1 for each mass fraction.If the sum of the mass fractions you enter is greater than 1, the values are normalized.You can use Cut , Copy , and Paste commands to enter the mass fraction values.
Water Content
Appears when Initial Conditions is set to Uniform.
Top Surface Water Content****Bottom Surface Water Content	Advanced FlowAdvanced Thermal-FlowAdvanced Thermal-Flow with ESC	Specify the water content method used for the top and bottom surfaces.NoneIndicates that the initial water content is not set.Film ThicknessSets the initial water content to the Film Thickness value that you specify for the thickness of the water layer present on the surface.Total MassSets the initial water content to the Total Mass value that you specify for the mass of the water present on the surface.Surface DensitySets the initial water content to the Surface Density value that you specify for the mass of the water over the area present on the surface.
File/Directory Selection
Appears when Initial Conditions is set to From Results in Other Directory or when Initial Temperature is set to From Results in Other Directory or From File (TEMPF format).
Results Directory	All	Sets the path to the directory that contains the TEMPF, flow.bfi, and flow.fli files. The TEMPF file contains the temperature results. The flow.bfi and flow.fli files contain the flow results.
Temperature File (TEMPF Format)	Thermal	Sets the location of the TEMPF file. The TEMPF solver file contains the temperature results.
Initial Condition Selection
Appears when Initial Conditions is set to From Results in Other Directory or when Initial Temperature is set to From Results in Other Directory or From File (TEMPF format).
Results to Use for Initial Conditions	All	Specifies which results to use from the previous solution based on the solution time.At Start TimeUses the results at start time of the current solution as the initial conditions.At Specified TimeUses the results from the time that you specify in the Initial Conditions Use Results at Time box as initial conditions.
Transient Thermal Loads
Appears when Initial Conditions or Initial Temperature are set to Perform Steady-State Solution.These options apply only for transient solutions.
Transient Thermal Loads to Use for Steady State Initial Conditions	All	Controls the initial conditions for time-varying thermal loads in the steady-state solution.At Specified TimeUses as the initial conditions, the value of the thermal load at the time that you specify in the Initial Conditions Use Loads at Time box.Average over TimeUses as the initial conditions, the value of the thermal load averaged over the complete transient run.Do Not Use Transient LoadsIgnores all defined time-varying boundary conditions for the steady-state analysis.

Learn more

Solution options

Thermal initial conditions

3D flow initial conditions

Turbulence Characteristics

Look up more details

Solution dialog box —Solution Details

Solution dialog box — Solution Units

Solution dialog box — Ambient Conditions

Solution dialog box —Restart

Solution dialog box —Thermal

Solution dialog box —3D Flow

Solution dialog box —Transient Setup

Solution dialog box — Results Options

Solution dialog box (Mapping) — Mapping Details

Solution dialog box (Mapping) — Optional Output

Quick links

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Thermal/Flow, Electronic Systems Cooling, and Space Systems Thermal

Simcenter 3D Thermal/Flow, Electronic Systems Cooling, and Space Systems Thermal boundary conditions

Solution dialog box — Initial Conditions , Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });