This unsteady simulation involves a moving body and demonstrates the use of chimera and 6-DOF modeling features in CFD-FASTRAN. The flow has a free stream Mach number of 0.5. The freestream temperature and pressure are 101325 Pa and 288.16K, respectively.

This unsteady simulation involves a moving body and demonstrates the useof chimera and 6-DOF modeling features in CFD-FASTRAN. The flow has a free stream Mach number of 2.0 at AOA of 5 deg. The free-stream temperature and pressure are 101325Pa and 288.16K, respectively. The simulation includes two separate 6DOF motion models. 6DOF model # 1 governs the motion of the second stage (payload vehicle), and 6DOFmodel # 2 governs the motion of the first stage (booster vehicle). The payload vehicle has a rocket nozzle that is modeled with a time dependent inlet condition simulating rocket ignition. First a steady-state solution of the combined vehicle flying at 5 deg. angle of attack is obtained. Then at time t=0, the rocket motor ignites and pressure builds up between the stages resulting in the separation of the two vehicles. The thrust integration option is employed to account for the thrust component at the nozzle chamber.

The objective of this tutorial is to understand the steps and methodology for creating unstructured grids. A simple 2-D plate (no thickness) is created and an unstructured grid is generated for it.

The near wall gridding is improved and modified through the use of sources and is demonstrated in this tutorial.

This example demonstrates the application of a user specified value of absorptivity for a simulation involving the solution to a Discrete Ordinate Method (DOM) radiation model. The UABSORPTIVITY subroutine sets a temperature dependent, species dependent value of absorptivity for the VC. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

The following user defined output example shows a method of writing out variables extracted from multiple volume conditions of the same name. The UOUT user subroutine saves the hassle of naming each one of the volume conditions uniquely, thus eliminating the need for having as many IF constructs in the user subroutine as there are VC’s of interest. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

Custom variables could be requested as output from the solver through the user subroutine UOUT. In this example, the temperature gradient (dT/dy component) along a line is written to a text file at the end of the simulation. This subroutine can be called under 6 different conditions based on the flag set (at the beginning, at the beginning of a run, at the beginning of a time step, at the end of each iteration, at the end of each time step and at the end of the run). User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

Custom variables could be requested as output from the solver through the user subroutine UOUT. This subroutine can be called under 6 different conditions based on the flag set (at the beginning, at the beginning of a run, at the beginning of a time step, at the end of each iteration, at the end of each time step and at the end of the run). The x-direction velocity across the height of the duct at a single plane is written to the .out file at the end of every iteration. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

This example demonstrates the application of a user specified value of porosity for a fluid volume condition. The user defined porosity option appears in CFD-GUI only when the user selects “Anisotropic Resistance” under “Resistance Model” for porous media VC settings. The CFD-ACE+ solver calls the UPOROUS user subroutine when it encounters the GUI setting “User Sub(uporous)” for any of the volume conditions in the DTF file. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

This tutorial sets up simulations of a atmospheric pressure thermal inductively coupled plasma including effects of radiation heat transfer and conjugated flow/wall heat transfer. The tutorial employs the power of user subroutines to define the properties of the Argon gas found in the plasma tube. The relative permittivity, electrical conductivity, specific heat and thermal conductivity of the Argon gas are set using the user subroutine. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

Many reaction mechanisms found in literature have generalized rate expressions. In this example, one such generalized reaction rate expression called the Langmuir - Hinshelwood formulation is implemented using the UREACTION_RATE_FACTOR user subroutine. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.

An enthalpy source term is used to simulate the transient heating of a room and implemented through the user subroutine USOURCE. A small region in the lower left hand corner of the "room" mimicks a heater. An inlet, directly above the heater, simulates a fan drawing cool (265° C) air from outdoors that helps circulate the heat. A pressure outlet located in the bottom right corner of the room provides an outlet vent. The top and right walls are isothermal (250° C), and the bottom and left walls are adiabatic. A single cell assigned as the "thermostat" is located near the upper right corner. When the temperature in this cell drops below 275° C, the heater is turned on. When the temperature at the thermostat rises above 285° C, the heater is turned off. User subroutines are built as Dynamic Link Libraries (DLL files for Windows) or shared objects (.so files for UNIX platforms). The shared libraries are then linked with CFD-ACE-SOLVER such that a two way communication between the solver and the user defined input is established.