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docs:utils:continuefields [2010/03/04 07:12]
gibson
docs:utils:continuefields [2010/03/04 17:35]
gibson
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 ====== continuefields ====== ====== continuefields ======
  
-Quadratic extrapolation of FlowField u(mu) as function of parameter mu+Quadratic extrapolation of FlowField u(mu) as function of parameter mu, where mu is one of Reynolds number, //dP/dx, Lx, Lz, Lx/Lz, sqrt(Lx^2 + Lz^2),// or the length between the starting //(Lx,Lz)// and a target value of //​(Lx,​Lz)//​. 
 ====== options ====== ====== options ======
  
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 </​code>​ </​code>​
 ====== Usage ====== ====== Usage ======
- 
 ===== start-up mode ===== ===== start-up mode =====
  
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 The trailing three arguments are directories containing results from a previous run of ''​continuesoln''​. The direction of continuation is determined by the order of the three previous solutions. ​ The trailing three arguments are directories containing results from a previous run of ''​continuesoln''​. The direction of continuation is determined by the order of the three previous solutions. ​
 +===== continuation parameter =====
  
 +''​continuesoln''​ will continue solutions in one of seven parameters:
 +   
 +   ​-contRe ​   --continueRe ​                  ​continue solution in Reynolds number ​                
 +   ​-contdPdx ​ --continuedPdx ​                ​continue solution in imposed pressure gradient ​     ​
 +   ​-contLx ​   --continueLx ​                  ​continue solution in streamwise width Lx             
 +   ​-contLz ​   --continueLz ​                  ​continue solution in spanwise width Lz               
 +   ​-contAsp ​  ​--continueAspect ​              ​continue solution in aspect ratio Lx/Lz              ​
 +   ​-contDiag ​ --continueDiagonal ​            ​continue solution along diagonal in Lx,Lz with const aspect ratio Lx/Lz                                                                                                              ​
 +   ​-contLtarg --continueLtarget ​             continue solution towards a specified Lx,Lz pair 
  
 +The target //Lx,Lz// for ''​-contLtarg''​ is specified by these options
 +
 +   ​-Lxtarg ​  ​--LxTarget ​         <​real> ​     default == 6.28319 ​    aim for this value of Lx                             
 +   ​-Lztarg ​  ​--LzTarget ​         <​real> ​     default == 3.14159 ​    aim for this value of Lz 
 +
 +Two other options related to the continuation type are 
 +
 +   ​-up ​      ​--upwards ​                      ​continue upwards in parameter (default is downwards)
 +   ​-adt ​     --adjustDt ​                     adjust dt between continuation steps to keep CFL in bounds ​
 +  ​
 +The ''​-up''​ option is self-explanatory. The ''​-adt''​ option is most important when the continuation changes //Lx//, since this will change the //x// gridspacing and consequently the CFL number. It should be safe to use ''​-adt''​ in other cases, too.
docs/utils/continuefields.txt · Last modified: 2010/03/04 17:35 by gibson