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20.6.1ʹÓÃÒ»°ã¶àÏàÁ÷Ä£Ð͵IJ½Ö裨Steps for Using the General Multiphase Models£© ÉèÖúÍÇó½âÒ»°ã¶àÏàÁ÷ÎÊÌâµÄ²½ÖèµÄÒªµãÈçÏ£¬¸÷¸ö×Ó²¿·ÖÏêϸµÄ½²ÊöÔÚËæºóµÄÕ½ÚÖС£¼ÇסÕâÀï¸ø³öµÄ½öÊÇÓëÒ»°ã¶àÏàÁ÷¼ÆËãÏà¹ØµÄ²½Öè¡£ÓйØÄãʹÓÃµÄÆäËüÄ£ÐͺÍÏà¹ØµÄ¶àÏàÁ÷Ä£Ð͵ÄÊäÈëµÄÏêϸÐÅÏ¢£¬½«ÔÚÕâЩģÐÍÖкÏÊʵIJ¿·Ö¸ø³ö¡£ ¼ûSection 20.6.2Óмò»¯Å·À­¶àÏàÁ÷Ä£ÄâµÄÖ¸ÄÏ¡£

1£®Ñ¡ÖÐÄãÏëҪʹÓõĶàÏàÁ÷Ä£ÐÍ£¨VOF, mixture, or Eulerian£©²¢Ö¸¶¨ÏàÊý¡£¶ÔVOFÄ£ÐÍ£¬Ò²Ö¸¶¨VOF¹«Ê½¡£ Define

Models Multiphase...

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See Sections 20.6.3 and 20.6.4 for details. 2.´Ó²ÄÁÏ¿âÖи´ÖÆÃèÊöÿÏàµÄ²ÄÁÏ¡£

Define Materials...

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!!Èç¹ûÄãµÄÄ£ÐÍÖк¬ÓÐ΢Á££¨granular£©Ï࣬Äã±ØÐëÔÚfluid materials categoryÖÐΪËü´´½¨Ð²ÄÁÏ£¨not the solid materials category£©

3£®¶¨ÒåÏָ࣬¶¨Ïà¼äµÄÏ໥×÷Óã¨interaction£©(ÀýÈ磬ʹÓÃOVFÄ£ÐÍʱµÄ±íÃæÕÅÁ¦£¨surface tension£©£¬Ê¹ÓûìºÏÄ£ÐÍʱµÄ»¬Á÷ËÙ¶È£¬Ê¹ÓÃÅ·À­Ä£ÐÍʱµÄdrag functions) Define Phases...

See Sections 20.6.7- 20.6.10 for details.

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Define Models Viscous... See Section 20.6.13 for details.

5£®Èç¹ûÌå»ýÁ¦´æÔÚ£¬turn on gravity and specify the gravitational acceleration.

Define Operating Conditions... See Section 20.6.11 for details. 6£®Ö¸¶¨±ß½çÌõ¼þ£¬°üÀ¨µÚ¶þÏàÌå»ý·Ý¶îÔÚÁ÷¶¯±ß½çºÍ£¨Èç¹ûÔÚVOFÄ£ÄâÖÐÄãÄ£Äâ±ÚÃæ¸½½ü£©±ÚÃæÉϵĽӴ¥½Ç¡£

Define Boundary Conditions... See Section 20.6.14 for details. 7£®ÉèÖÃÄ£Äâ¾ßÌåµÄ½â²ÎÊý

Solve Controls Solution...

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Solve Initialize Patch... See Section 20.6.15 for details. 9£®¼ÆËãÇó½âºÍ¼ì²é½á¹û

See Sections 20.7 and 20.8 for details.

20.6.2Å·À­¶àÏàÁ÷Ä£ÄâµÄ¸½¼ÓÖ¸ÄÏ£¨Additional Guidelines for Eulerian Multiphase Simulations£©

Ò»µ©Äã¾ö¶¨ÁËÅ·À­¶àÏàÁ÷Ä£ÐÍÊʺÏÄãµÄÎÊÌ⣨as described in Sections 18.4 and 20.1£©£¬ÄãÓ¦µ±¿¼ÂÇÇó½âÄãµÄ¶àÏàÁ÷ÎÊÌâµÄÐèÇó¼ÆËãÄÜÁ¦¡£ÒªÇóµÄ¼ÆËãÄÜÁ¦ºÜÇ¿µÄÒÀÀµÓÚËùÇó½âµÄÊäÔË·½³ÌµÄ¸öÊýºÍñîºÏ³Ì¶È¡£¶ÔÅ·À­¶àÏàÁ÷Ä£ÐÍ£¬ÓдóÊýÁ¿µÄ¸ß¶ÈñîºÏµÄÊäÔË·½³Ì£¬¼ÆËãµÄºÄ·Ñ½«ºÜ¸ß£¬ÔÚÉèÖÃÄãµÄÎÊÌâǰ£¬¾¡¿ÉÄܼõÉÙÎÊÌâµÄstatementµ½×î¼ò»¯µÄ¿ÉÄÜÐÎʽ¡£ ÔÚÄ㿪ʼµÚÒ»´ÎÇó½â³¢ÊÔ£¬È¡¶ø´úÖ®¾¡Á¦È¥Çó½â¶àÏàÁ÷¶¯µÄËùÓеĸ´ÔÓ·½Ã棬Äã¿ÉÒÔÒÔ¼òµ¥½üËÆµØ¿ªÊ¼²¢ÇÒÖªµÀÎÊÌⶨÒåµÄ×îÖÕÐÎʽ¡£¼ò»¯¶àÏàÁ÷ÎÊÌâµÄһЩ½¨ÒéÁоÙÈçÏ£º

1£® ʹÓÃÁùÃæÌå»òËıßÐÎÍø¸ñ£¨¶ø²»ÓÃËÄÃæÌå»òÈý½ÇÐÎÍø¸ñ£©¡£ 2£® ¼õÉÙÏàµÄÊýÄ¿¡£

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See Section 20.7.3 for more solution strategies for Eulerian multiphase calculations.

20.6.3Ñ¡ÓöàÏàÁ÷Ä£ÐͲ¢Ö¸¶¨ÏàÊý£¨Enabling the Multiphase Model and Specifying the

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Number of Phases£©

ΪÁËÑ¡VOF, mixture, Eulerian¶àÏàÁ÷Ä£ÐÍ£¬ÔÚMultiphase Model panel (Figure 20.6.1)ÏÂÑ¡Volume of Fluid, Mixture, or Eulerian as the Model¡£ Define

Models

Multiphase...

Figure 20.6.1: The Multiphase Model Panel

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number of phases

VOF formulation (see Section 20.6.4)

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number of phases

whether or not to compute the slip velocities (see Section 20.6.5) (optional) implicit body force formulation (see Section 20.6.11) (optional) cavitation effects (see Section 20.6.6)

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