Wind-US User's Guide - Keyword Reference, TTSPEC

(Wind-US Documentation Home Page) (Wind-US User's Guide) (GMAN User's Guide) (MADCAP User's Guide) (CFPOST User's Guide) (Wind-US Utilities) (Common File User's Guide) (Wind-US Installation Guide) (Wind-US Developer's Reference) (Guidelines Documents)

(Introduction) (Tutorial) (Geometry and Flow Physics Modeling) (Numerical Modeling) (Boundary Conditions) (Convergence Monitoring) (Files) (Scripts) (Parallel Processing) (Keyword Reference) (Test Options)

TTSPEC - Wall temperature and transition (block)

Structured Grids

TTSPEC TYPE {TEMPERATURE | TRANSITION} ZONE zone_number MODE {CURRENT | FILE filename | CHT} UPDATE [INTERVAL] frequency SURFACE surfname ENDTTSPEC

For structured grids, this keyword block allows a point-by-point surface temperature boundary condition to be used, and/or point-by-point boundary layer transition information to be specified. Surface temperature and transition data may be specified for any boundary surface in any zone. [Note, though, that although Wind-US allows temperature/transition data to be specified on any boundary surface, the tmptrn utility used to add the data to the .cfl file currently does not allow specification on the i₁ or i_max surface.] The maximum total number of temperature/transition surfaces, combined, is determined by the Fortran parameter MAXTTS, currently equal to 20.

The normal procedure is to do an initial run, perhaps with just a few cycles, without specifying temperature/transition information, to create an initial common flow (.cfl) file. The temperature/transition data is then created and added to the .cfl file using the tmptrn utility.

For backward compatibility with early versions of Wind, however, the temperature/transition data may be read from separate ASCII files, one for each applicable surface, created with the older tmptrn utility. This would only be necessary during the initial (i.e., non-restart) run, since Wind-US will automatically store the data in the .cfl file, where it can be read during subsequent runs.

In addition, in earlier versions of tmptrn, the temperature written into the .cfl file was in K, instead of being non-dimensionalized. This error was fixed in version 1.8 of tmptrn. However, some versions of Wind-US had coding to accommodate the dimensional temperature value, and these versions will not work with temperature distributions written using tmptrn 1.8 and above. See the tmptrn documentation for details.

The various elements of the TTSPEC keyword block are defined as follows:

TYPE {TEMPERATURE | TRANSITION}

This keyword indicates whether a surface temperature distribution or boundary layer transition information is being specified.

ZONE zone_number

This keyword specifies the number of the zone containing the boundary surface along which temperature or transition data is being specified.

MODE {CURRENT | FILE filename | CHT}

This keyword specifies where the surface temperature or transition data is obtained.

	`CURRENT`		The data is stored in the flow (.cfl) file.

	`FILE filename`		The data is stored in the ASCII file filename, created using the older tmptrn utility distributed with early versions of Wind. If filename is specified without an extension, an extension of .dat is assumed. This option is included for backward compatibility only, using existing files created with the older tmptrn utility, and is only needed for an initial (i.e., non-restart) run. Subsequent (i.e., restart) runs should use `MODE CURRENT`. New applications should use the latest tmptrn utility to write the temperature/transition data into the .cfl file directly.

	`CHT`		Wall temperatures are computed using an external loosely-coupled conjugate heat transfer code (HTX). This mode only applies when temperature is being specified, not boundary layer transition. The Wind-US executable being used must contain the appropriate Surface Data Interface library routines, which are distributed separately. Please see the following references for additional instructions on using the conjugate heat transfer capability: Wind-US_CHT_Documentation.pdf HTX_Manual.pdf Additional information on the HTX code and the above manuals are available here.

UPDATE [INTERVAL] frequency

When MODE CHT is used, wall temperatures will be updated every frequency cycles. This keyword does not apply to other MODE options.

SURFACE surfname

This keyword specifies the boundary surface in zone zone_number along which temperature or transition data is being specified. Currently, the applicable surface names are I1, IMAX, J1, JMAX, K1, and KMAX, corresponding to the i₁, i_max, j₁, j_max, k₁, and k_max surfaces, respectively.

Note: In versions of Wind-US prior to 3.39, the keyword SUBSET ALL had to be specified, once for each surface, to properly update the total number of temperature/transition surfaces. That's not only no longer necessary, but should not be done. Existing input data (.dat) files should be modified to remove any SUBSET ALL keywords in TTSPEC keyword blocks.

Example

As an example, suppose we are specifying the wall temperature distribution along the j₁ surface in zone 1, and the j₁ and j_max surfaces in zone 2. In addition, suppose we're specifying boundary layer transition along the j₁ surface in zone 1. If existing temperature/transition files are being used, created with the older tmptrn utility, the TTSPEC keyword block for the initial run might be

   TTSPEC
      TYPE TEMPERATURE
         ZONE 1
            MODE FILE temp.z1j1.asc
            SURFACE J1
         ZONE 2
            MODE FILE temp.z2j1.asc
            SURFACE J1
            MODE FILE temp.z2jm.asc
            SURFACE JMAX
      TYPE TRANSITION
         ZONE 1
            MODE FILE tran.z1j1.asc
            SURFACE J1
   ENDTTSPEC

Since the temperature/transition data will be written into the .cfl file during the initial run, later (i.e., restart) runs could use

   TTSPEC
      TYPE TEMPERATURE
         ZONE 1
            MODE CURRENT
            SURFACE J1
         ZONE 2
            MODE CURRENT
            SURFACE J1
            SURFACE JMAX
      TYPE TRANSITION
         ZONE 1
            MODE CURRENT
            SURFACE J1
   ENDTTSPEC

See Also: WALL TEMPERATURE

Last updated 1 Apr 2016