PAT312, Section 39, December 2006 S39-1 Copyright 2007 MSC.Software Corporation SECTION 39 LBCS USING FIELDS AND MICROFUNCTIONS. - презентация

1 PAT312, Section 39, December 2006 S39-1 Copyright 2007 MSC.Software Corporation SECTION 39 LBCS USING FIELDS AND MICROFUNCTIONS

2 PAT312, Section 39, December 2006 S39-2 Copyright 2007 MSC.Software Corporation

3 PAT312, Section 39, December 2006 S39-3 Copyright 2007 MSC.Software Corporation FIELDS AND MICROFUNCTIONS l Fields and microfunctions are used to introduce variations in LBCs: l Spatial including (new) time dependent spatial fields l Time l Temperature l Spatial fields selected directly within Patran l Temperature and Heating LBCs l Non-spatial general Field, with MACRO template l MFID (MicroFunction ID) l Convection LBCs l Material property Field, with CONV template l MPID (Material Property ID ) l Exceptions: Time Table and Temperature Table LBCs created directly in Patran dont require a template

4 PAT312, Section 39, December 2006 S39-4 Copyright 2007 MSC.Software Corporation l Template Ids specified in the MSC.Thermal Boundary Condition form point into the MACRO template in the template.dat.apnd file l Format of TEMPERATURE or HEAT template is as follows Template ID Specified in MSC.Patran Number of Microfunctions Node 1 Node 2 Scale Factor Microfunction IDs l The functional variation is derived from the microfunctions l MSC.Thermal has 21 microfunctions HEAT & TEMPERATURE MACRO TEMPLATE

5 PAT312, Section 39, December 2006 S39-5 Copyright 2007 MSC.Software Corporation MICROFUNCTION OPTIONS 1. Constant 2. Power Series 3. Sine Wave 4. Square Wave 5. Step 6. Ramp 7. Exponential 8. User table, linear interpolation 9. User table, hermite polynomial interpolation with quadratic interpolation/extrapolation at end points 10. Repeating wave, linear interpolation 11. Repeating Wave, hermite polynomial interpolation 12. Natural logarithm 13. Base 10 logarithm 14. Blackbody radiation (determines fraction of blackbody radiant energy between two wavelengths) 15. Flip flop 16. Dead band (allows for hysteresis) 17. Straight line function 18. Data table, indexed linear interpolation 19. Data table, indexed hermite polynomial interpolation 20. Repeating waveform, indexed linear interpolation 21. Repeating waveform, indexed hermite polynomial interpolation 22. Repeating flip flop 23. (23-999) Reserved for future use (1001+)User defined function

6 PAT312, Section 39, December 2006 S39-6 Copyright 2007 MSC.Software Corporation micro.dat FILE l Microfunction information is written to the micro.dat file l MSC.Patran automatically writes micro.dat l Format of micro.dat: Argument signifies independent variable 0 Time 1 Temperature 2 Temperature diff. (T(1)-T(2)) 3 Radiosity difference *(T(1))**4 – T(2)**4) 4 Average temperatures (T(1) + T(2))/2.0 Keyword (Start in Column 1) MICROFUNCTION ID l OPTION: Identifies function library option. If the function library option is input as negative, the reciprocal of the function will be used. (e.g. Sin(R) would be evaluated as (1/Sin(R))) l Keyword (MICDAT) followed by appropriate data for the option selected.

7 PAT312, Section 39, December 2006 S39-7 Copyright 2007 MSC.Software Corporation MICRO.DAT FILE (Cont.) l Microfunction definition is completed with a / in column 1 l Multiple MACROs applied to a node are summed l A MACRO result is the product of all microfunctions Q macro or T macro = F 1 * F 2 * F n *FACTOR Q NODE or T NODE = Q MACRO or T MACRO

8 PAT312, Section 39, December 2006 S39-8 Copyright 2007 MSC.Software Corporation MICROFUNCTIONS FROM MSC.PATRAN l Microfunctions are created from MSC.Patran under the Fields/Non Spatial/General selection l The Microfunctions are created in MSC.Patran are translated into the micro.dat file in the jobname directory l The translation is performed when the Apply button is clicked on the Analysis form

9 PAT312, Section 39, December 2006 S39-9 Copyright 2007 MSC.Software Corporation MICROFUNCTIONS IN MSC.PATRAN l On the Fields form select: l Object: Non Spatial l Method: General l Select the appropriate microfunction option

10 PAT312, Section 39, December 2006 S39-10 Copyright 2007 MSC.Software Corporation MICROFUNCTIONS FROM MSC.PATRAN l Enter data on the microfunction form l Enter a microfunction ID (MFID) or use the default l Select the Independent variable type: l Time l Temperature l Temperature Difference l Radiosity Difference l Average temperature l The micro.dat file is written to the jobname subdirectory when you click Apply on the Analysis form

11 PAT312, Section 39, December 2006 S39-11 Copyright 2007 MSC.Software Corporation

12 PAT312, Section 39, December 2006 S39-12 Copyright 2007 MSC.Software Corporation