- Nektar-users - imperial.ac.uk

Re: [Nektar-users] Restart using VCSMapping solver
by Wang, Zhicheng 10 Mar '20

10 Mar '20

Hi Robin, thank you. yes, it works fine without restart the *.map files. On Tue, Mar 10, 2020, 2:47 AM Basso, Robin G <r.basso17(a)imperial.ac.uk> wrote: > Hi Wang, > > I would suggest to try the restart first in 2D, from a 2D simulation. > Once you are confident with that you can try with your homogeneous > direction. > Does your session file running fine without restart from file? > > Best, > Robin. > > On 9 Mar 2020, at 20:37, Wang, Zhicheng <zhicheng_wang(a)brown.edu> wrote: > > Hi Robin, Thank you very much for your kind reply. > I have tried the approach you mentioned, but it complained that something > was wrong for the 3DH1D simulation, please see the errors below, > > ************************************begin > error***************************************************************** > Field z not found. > Field z not found. > Field z not found. > Field z not found. > Fatal : Level 0 assertion violation > 3DH1D does not support mapping in the z-direction. > Fatal : Level 0 assertion violation > 3DH1D does not support mapping in the z-direction. > ****************************************end error > **************************************************************** > > > > > *Also, I copy all the condition parameters here, The case I'm running is > 2D VIV of a rigid cylinder. Maybe I have misused some parameters ?* > > <CONDITIONS> > <SOLVERINFO> > > > > > > > > > > > > > > > > </SOLVERINFO> > > <PARAMETERS> > TimeStep = 0.0025 > FinalTime = 1000 > NumSteps = FinalTime/TimeStep > IO_CheckSteps = 500 > IO_InfoSteps = 25 > IO_CFLSteps = 25 > Re = 500 > Kinvis = 1/Re > HomModesZ = 2 > LZ = 0.01 > evm_alpha = 0.1 > evm_beta = 0.1 > evm_start_step = 2 > evm_reduced_order = 1 > StructFreqY = 0.17 > StructFreqX = 0.34 > StructStiff = 0.0 > StructRho = 1.5708 > CableTension = 0.0 > BendingStiff = 0.0 > FictDamp = 0.0 > FictMass = 1.5 > </PARAMETERS> > > <VARIABLES> > <V ID="0"> u </V> > <V ID="1"> v </V> > <V ID="2"> w </V> > <V ID="3"> p </V> > </VARIABLES> > > <BOUNDARYREGIONS> > C[5]  > C[3]  > C[4]  > C[2]  > C[1]  > </BOUNDARYREGIONS> > > <BOUNDARYCONDITIONS> > <REGION REF="0"> > <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <D VAR="w" VALUE="0" /> > <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > </REGION> > <REGION REF="1"> > > > > > </REGION> > <REGION REF="2"> > > > > > </REGION> > <REGION REF="3"> > <N VAR="u" VALUE="0" /> > <N VAR="v" VALUE="0" /> > <N VAR="w" VALUE="0" /> > <D VAR="p" VALUE="0" /> > </REGION> > <REGION REF="4"> > <D VAR="u" VALUE="1" /> > <D VAR="v" VALUE="0" /> > <D VAR="w" VALUE="0" /> > <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > </REGION> > </BOUNDARYCONDITIONS> > > <FUNCTION NAME="InitialConditions"> > <F FILE="cyl.rst" /> > </FUNCTION> > > <FUNCTION NAME="ExactSolution"> > <E VAR="u" VALUE="1" /> > <E VAR="v" VALUE="0" /> > <E VAR="w" VALUE="0" /> > <E VAR="p" VALUE="0" /> > </FUNCTION> > > <FUNCTION NAME="Mapping"> > <F FILE="cyl.map.rst" /> > </FUNCTION> > > <FUNCTION NAME="MappingVel"> > <F FILE="cyl.map.rst" /> > </FUNCTION> > > <FUNCTION NAME="displacements"> > <E VAR="x" VALUE="0.0" /> > <E VAR="y" VALUE="A*cos(omega*t)*cos(2*PI*z/LZ)" /> > </FUNCTION> > <FUNCTION NAME="velocities"> > <E VAR="x" VALUE="0.0" /> > <E VAR="y" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" /> > </FUNCTION> > <FUNCTION NAME="accelerations"> > <E VAR="x" VALUE="0.0" /> > <E VAR="y" > VALUE="-1.0*omega*omega*A*cos(omega*t)*cos(2*PI*z/LZ)" /> > </FUNCTION> > > <FUNCTION NAME="MappingFile"> > <F FILE="cyl.map.rst" /> > </FUNCTION> > > </CONDITIONS> > > <MAPPING TYPE="XYofZ"> > <COORDS>Mapping</COORDS> > <VEL>MappingVel</VEL> > <TIMEDEPENDENT>True</TIMEDEPENDENT> > </MAPPING> > > <FORCING> > <FORCE TYPE="MovingBody"> > <DISPLACEMENTS> displacements </DISPLACEMENTS> > <VELOCITIES> velocities </VELOCITIES> > <ACCELERATIONS> accelerations </ACCELERATIONS> > <PARAM NAME="OutputFile">TensionedCable</PARAM> > <PARAM NAME="OutputFrequency">25</PARAM> > <PARAM NAME="Boundary"> B[0] </PARAM> > </FORCE> > </FORCING> > > <FILTER TYPE="HistoryPoints"> > <PARAM NAME="OutputFile">TimeValues</PARAM> > <PARAM NAME="OutputFrequency">10</PARAM> > <PARAM NAME="Points"> > 3.0 0.0 0.0 > 5.0 0.0 0.0 > 7.0 0.0 0.0 > </PARAM> > </FILTER> > </FILTERS> > > > Best, > Zhicheng > > On Mon, Mar 9, 2020 at 4:18 PM Basso, Robin G <r.basso17(a)imperial.ac.uk> > wrote: > >> Hi, >> >> I attached an example of a simulation of two cylinders restarted from >> file. >> >> You need to create two functions, namely mapping and mappingVel for >> instance, where you call your .map file that contains the mesh deformation >> and velocity. >> Then you need to specify in your mapping tag that you restart your >> simulation from this file, calling these two function (defining coords and >> velocity). >> >> I hope this helps, tell me if you can’t make it work. >> >> Best, >> Robin. >> >> >> >> <?xml version="1.0" encoding="utf-8" ?> >> <NEKTAR> >> <EXPANSIONS> >> <E COMPOSITE="C[119]" NUMMODES="5" TYPE="MODIFIED" FIELDS="u,v,p" >> /> >> </EXPANSIONS> >> <CONDITIONS> >> <SOLVERINFO> >> >> > "UnsteadyNavierStokes" /> >> >> >> > "XxtMultiLevelStaticCond"/> >> >> >> >> </SOLVERINFO> >> >> <PARAMETERS> >> TimeStep = 0.004 >> T = 40 >> NumSteps = T/TimeStep >> IO_CheckSteps = NumSteps/200 >> IO_InfoSteps = 10 >> IO_CFLSteps = 10 >> Re = 150 >> Kinvis = 1/Re >> >> forcedAmplitudeY = 0.5 >> forcedAmplitudeX = 0.2*forcedAmplitudeY >> forcedFreqY = 1.5*0.2 >> forcedFreqX = 2*forcedFreqY >> >> MappingPressureTolerance = 1e-6 >> MappingViscousTolerance = 1e-8 >> MappingPressureRelaxation = 0.4 >> MappingViscousRelaxation = 0.4 >> >>  >> Mr = 4.0 >> Cr = 0.007 >> Vr = 10.0 >> >> fn = 1.0/Vr >> M = Mr * PI / 4.0 >> K = M* ( 2*PI *fn ) * ( 2*PI *fn ) >> C = Cr * 2 * sqrt(K*M) >> </PARAMETERS> >> >> <VARIABLES> >> <V ID="0"> u </V> >> <V ID="1"> v </V> >> <V ID="2"> p </V> >> </VARIABLES> >> >> <BOUNDARYREGIONS> >> C[125-126]  >> C[120-121]  >> C[122]  >> C[123-124]  >> </BOUNDARYREGIONS> >> >> <BOUNDARYCONDITIONS> >> <REGION REF="0"> >> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> >> <D VAR="x" VALUE="0" /> >> <D VAR="y" VALUE="0" /> >> </REGION> >> <REGION REF="1"> >> <D VAR="u" VALUE="1" /> >> <D VAR="v" VALUE="0" /> >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> >> <D VAR="x" VALUE="0" /> >> <D VAR="y" VALUE="0" /> >> </REGION> >> <REGION REF="2"> >> <N VAR="u" VALUE="0" /> >> <N VAR="v" VALUE="0" /> >> <D VAR="p" VALUE="0" /> >> <D VAR="x" VALUE="0" /> >> <D VAR="y" VALUE="0" /> >> </REGION> >> <REGION REF="3"> >> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> >> <D VAR="x" VALUE="0" /> >> <D VAR="y" VALUE="0" /> >> </REGION> >> </BOUNDARYCONDITIONS> >> >> <FUNCTION NAME="Displacement"> >> <E VAR="x" VALUE="forcedAmplitudeX*sin(2*PI*forcedFreqX*t)" >> /> >> <E VAR="y" VALUE="forcedAmplitudeY*sin(2*PI*forcedFreqY*t)" >> /> >> </FUNCTION> >> >> <FUNCTION NAME="InitialConditions"> >> <F FILE="2cyl.fld" /> >> </FUNCTION> >> >> <FUNCTION NAME="Mapping"> >> <F FILE="2cyl.map" /> >> </FUNCTION> >> >> <FUNCTION NAME="MappingVel"> >> <F FILE="2cyl.map" /> >> </FUNCTION> >> >> </CONDITIONS> >> >> <MAPPING TYPE="XYofXY"> >> <COORDS> Mapping </COORDS> >> <VEL> MappingVel </VEL> >> </MAPPING> >> >> <FSI TYPE="General" > >> <BODY TYPE="Rigid" > >> <PARAM NAME="Boundary"> B[0] </PARAM> >> <PARAM NAME="OutputFile"> downCyl </PARAM> >> <PARAM NAME="OutputFrequency"> 10 </PARAM> >> <PARAM NAME="TranslationDOFs"> 1 </PARAM> >> <PARAM NAME="Direction1"> 0.0 1.0 0.0</PARAM> >> <PARAM NAME="StartTime"> 0.0 </PARAM> >> <PARAM NAME="M"> M </PARAM> >> <PARAM NAME="C"> C </PARAM> >> <PARAM NAME="K"> K </PARAM> >> </BODY> >> <BODY TYPE="Forced" > >> <PARAM NAME="Boundary"> B[3] </PARAM> >> <PARAM NAME="DisplacementFCN"> Displacement </PARAM> >> </BODY> >> </FSI> >> >> <FILTERS> >> <FILTER TYPE="AeroForces"> >> <PARAM NAME="OutputFile"> forcesDownCyl </PARAM> >> <PARAM NAME="OutputFrequency"> 10 </PARAM> >> <PARAM NAME="Boundary"> B[0] </PARAM> >> </FILTER> >> <FILTER TYPE="AeroForces"> >> <PARAM NAME="OutputFile"> forcesUpCyl </PARAM> >> <PARAM NAME="OutputFrequency"> 10 </PARAM> >> <PARAM NAME="Boundary"> B[3] </PARAM> >> </FILTER> >> </FILTERS> >> >> <GEOMETRY DIM="2" SPACE="2"> >> <VERTEX COMPRESSED="B64Z-LittleEndian" BITSIZE="64"> >> eJxtm3dgT9cbxr8SRCLIED+1d+0Zm9yrlBqNaM2qUZuiiqhSI2IlSI1WSKVUiYpYIcS8MWpTu2YJsXcUIcavbd73vfc+99x/XsnHOd/zfe5z3vPec09yurKutg2DPqmUVChFy3Xu29S1vjr92pXNZbtSNp0OH2Pl2SnuzxwYGXvO18HdKUYWeuI5/qpHCv0oHC4HzwH9I3eD/vHzPeD7Yftcto8v4/j+nsCxvReMv+oknwvb2xYVnhvGh9wbvh/yPDD+zUl9zlt5Xhgf8nw >> >> >> On 9 Mar 2020, at 19:41, Sherwin, Spencer J <s.sherwin(a)imperial.ac.uk> >> wrote: >> >> Hi Robin, >> >> Could you help Zhicheng with this request. >> >> Thanks, >> Spencer. >> >> >> On 5 Mar 2020, at 22:59, Wang, Zhicheng <zhicheng_wang(a)brown.edu> wrote: >> >> This email from zhicheng_wang(a)brown.edu originates from outside >> Imperial. Do not click on links and attachments unless you recognise the >> sender. If you trust the sender, add them to your safe senders list >> <https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email >> stamping for this address. >> >> Hi nektar++ users, >> Is there anyone can give me a hint how to restart a simulation using the >> VCSMapping solver ? >> I see folders named *.chk and *.map, but how to use the *.map file to >> restart a new simulation ? >> >> Best, >> Zhicheng >> _______________________________________________ >> Nektar-users mailing list >> Nektar-users(a)imperial.ac.uk >> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users >> >> >> Spencer Sherwin FREng, FRAeS >> Head of Aerodynamics Section, >> Director of Research Computing Service, >> Professor of Computational Fluid Mechanics, >> Department of Aeronautics, >> s.sherwin(a)imperial.ac.uk South >> Kensington Campus, >> Phone: +44 (0)20 7594 5052 Imperial College >> London, >> Fax: +44 (0)20 7594 1974 London, SW7 2AZ, >> UK >> http://www.imperial.ac.uk/people/s.sherwin/ >> >> >> >

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Re: [Nektar-users] Restart using VCSMapping solver
by Wang, Zhicheng 09 Mar '20

09 Mar '20

Hi Robin, Thank you very much for your kind reply. I have tried the approach you mentioned, but it complained that something was wrong for the 3DH1D simulation, please see the errors below, ************************************begin error***************************************************************** Field z not found. Field z not found. Field z not found. Field z not found. Fatal : Level 0 assertion violation 3DH1D does not support mapping in the z-direction. Fatal : Level 0 assertion violation 3DH1D does not support mapping in the z-direction. ****************************************end error **************************************************************** *Also, I copy all the condition parameters here, The case I'm running is 2D VIV of a rigid cylinder. Maybe I have misused some parameters ?* <CONDITIONS> <SOLVERINFO> </SOLVERINFO> <PARAMETERS> TimeStep = 0.0025 FinalTime = 1000 NumSteps = FinalTime/TimeStep IO_CheckSteps = 500 IO_InfoSteps = 25 IO_CFLSteps = 25 Re = 500 Kinvis = 1/Re HomModesZ = 2 LZ = 0.01 evm_alpha = 0.1 evm_beta = 0.1 evm_start_step = 2 evm_reduced_order = 1 StructFreqY = 0.17 StructFreqX = 0.34 StructStiff = 0.0 StructRho = 1.5708 CableTension = 0.0 BendingStiff = 0.0 FictDamp = 0.0 FictMass = 1.5 </PARAMETERS> <VARIABLES> <V ID="0"> u </V> <V ID="1"> v </V> <V ID="2"> w </V> <V ID="3"> p </V> </VARIABLES> <BOUNDARYREGIONS> C[5]  C[3]  C[4]  C[2]  C[1]  </BOUNDARYREGIONS> <BOUNDARYCONDITIONS> <REGION REF="0"> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> <D VAR="w" VALUE="0" /> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> </REGION> <REGION REF="1"> </REGION> <REGION REF="2"> </REGION> <REGION REF="3"> <N VAR="u" VALUE="0" /> <N VAR="v" VALUE="0" /> <N VAR="w" VALUE="0" /> <D VAR="p" VALUE="0" /> </REGION> <REGION REF="4"> <D VAR="u" VALUE="1" /> <D VAR="v" VALUE="0" /> <D VAR="w" VALUE="0" /> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> </REGION> </BOUNDARYCONDITIONS> <FUNCTION NAME="InitialConditions"> <F FILE="cyl.rst" /> </FUNCTION> <FUNCTION NAME="ExactSolution"> <E VAR="u" VALUE="1" /> <E VAR="v" VALUE="0" /> <E VAR="w" VALUE="0" /> <E VAR="p" VALUE="0" /> </FUNCTION> <FUNCTION NAME="Mapping"> <F FILE="cyl.map.rst" /> </FUNCTION> <FUNCTION NAME="MappingVel"> <F FILE="cyl.map.rst" /> </FUNCTION> <FUNCTION NAME="displacements"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="A*cos(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="velocities"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="accelerations"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="-1.0*omega*omega*A*cos(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="MappingFile"> <F FILE="cyl.map.rst" /> </FUNCTION> </CONDITIONS> <MAPPING TYPE="XYofZ"> <COORDS>Mapping</COORDS> <VEL>MappingVel</VEL> <TIMEDEPENDENT>True</TIMEDEPENDENT> </MAPPING> <FORCING> <FORCE TYPE="MovingBody"> <DISPLACEMENTS> displacements </DISPLACEMENTS> <VELOCITIES> velocities </VELOCITIES> <ACCELERATIONS> accelerations </ACCELERATIONS> <PARAM NAME="OutputFile">TensionedCable</PARAM> <PARAM NAME="OutputFrequency">25</PARAM> <PARAM NAME="Boundary"> B[0] </PARAM> </FORCE> </FORCING> <FILTER TYPE="HistoryPoints"> <PARAM NAME="OutputFile">TimeValues</PARAM> <PARAM NAME="OutputFrequency">10</PARAM> <PARAM NAME="Points"> 3.0 0.0 0.0 5.0 0.0 0.0 7.0 0.0 0.0 </PARAM> </FILTER> </FILTERS> Best, Zhicheng On Mon, Mar 9, 2020 at 4:18 PM Basso, Robin G <r.basso17(a)imperial.ac.uk> wrote: > Hi, > > I attached an example of a simulation of two cylinders restarted from file. > > You need to create two functions, namely mapping and mappingVel for > instance, where you call your .map file that contains the mesh deformation > and velocity. > Then you need to specify in your mapping tag that you restart your > simulation from this file, calling these two function (defining coords and > velocity). > > I hope this helps, tell me if you can’t make it work. > > Best, > Robin. > > > > <?xml version="1.0" encoding="utf-8" ?> > <NEKTAR> > <EXPANSIONS> > <E COMPOSITE="C[119]" NUMMODES="5" TYPE="MODIFIED" FIELDS="u,v,p" > /> > </EXPANSIONS> > <CONDITIONS> > <SOLVERINFO> > > "UnsteadyNavierStokes" /> > > > "XxtMultiLevelStaticCond"/> > > > > </SOLVERINFO> > > <PARAMETERS> > TimeStep = 0.004 > T = 40 > NumSteps = T/TimeStep > IO_CheckSteps = NumSteps/200 > IO_InfoSteps = 10 > IO_CFLSteps = 10 > Re = 150 > Kinvis = 1/Re > > forcedAmplitudeY = 0.5 > forcedAmplitudeX = 0.2*forcedAmplitudeY > forcedFreqY = 1.5*0.2 > forcedFreqX = 2*forcedFreqY > > MappingPressureTolerance = 1e-6 > MappingViscousTolerance = 1e-8 > MappingPressureRelaxation = 0.4 > MappingViscousRelaxation = 0.4 > >  > Mr = 4.0 > Cr = 0.007 > Vr = 10.0 > > fn = 1.0/Vr > M = Mr * PI / 4.0 > K = M* ( 2*PI *fn ) * ( 2*PI *fn ) > C = Cr * 2 * sqrt(K*M) > </PARAMETERS> > > <VARIABLES> > <V ID="0"> u </V> > <V ID="1"> v </V> > <V ID="2"> p </V> > </VARIABLES> > > <BOUNDARYREGIONS> > C[125-126]  > C[120-121]  > C[122]  > C[123-124]  > </BOUNDARYREGIONS> > > <BOUNDARYCONDITIONS> > <REGION REF="0"> > <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > <D VAR="x" VALUE="0" /> > <D VAR="y" VALUE="0" /> > </REGION> > <REGION REF="1"> > <D VAR="u" VALUE="1" /> > <D VAR="v" VALUE="0" /> > <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > <D VAR="x" VALUE="0" /> > <D VAR="y" VALUE="0" /> > </REGION> > <REGION REF="2"> > <N VAR="u" VALUE="0" /> > <N VAR="v" VALUE="0" /> > <D VAR="p" VALUE="0" /> > <D VAR="x" VALUE="0" /> > <D VAR="y" VALUE="0" /> > </REGION> > <REGION REF="3"> > <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > <D VAR="x" VALUE="0" /> > <D VAR="y" VALUE="0" /> > </REGION> > </BOUNDARYCONDITIONS> > > <FUNCTION NAME="Displacement"> > <E VAR="x" VALUE="forcedAmplitudeX*sin(2*PI*forcedFreqX*t)" /> > <E VAR="y" VALUE="forcedAmplitudeY*sin(2*PI*forcedFreqY*t)" /> > </FUNCTION> > > <FUNCTION NAME="InitialConditions"> > <F FILE="2cyl.fld" /> > </FUNCTION> > > <FUNCTION NAME="Mapping"> > <F FILE="2cyl.map" /> > </FUNCTION> > > <FUNCTION NAME="MappingVel"> > <F FILE="2cyl.map" /> > </FUNCTION> > > </CONDITIONS> > > <MAPPING TYPE="XYofXY"> > <COORDS> Mapping </COORDS> > <VEL> MappingVel </VEL> > </MAPPING> > > <FSI TYPE="General" > > <BODY TYPE="Rigid" > > <PARAM NAME="Boundary"> B[0] </PARAM> > <PARAM NAME="OutputFile"> downCyl </PARAM> > <PARAM NAME="OutputFrequency"> 10 </PARAM> > <PARAM NAME="TranslationDOFs"> 1 </PARAM> > <PARAM NAME="Direction1"> 0.0 1.0 0.0</PARAM> > <PARAM NAME="StartTime"> 0.0 </PARAM> > <PARAM NAME="M"> M </PARAM> > <PARAM NAME="C"> C </PARAM> > <PARAM NAME="K"> K </PARAM> > </BODY> > <BODY TYPE="Forced" > > <PARAM NAME="Boundary"> B[3] </PARAM> > <PARAM NAME="DisplacementFCN"> Displacement </PARAM> > </BODY> > </FSI> > > <FILTERS> > <FILTER TYPE="AeroForces"> > <PARAM NAME="OutputFile"> forcesDownCyl </PARAM> > <PARAM NAME="OutputFrequency"> 10 </PARAM> > <PARAM NAME="Boundary"> B[0] </PARAM> > </FILTER> > <FILTER TYPE="AeroForces"> > <PARAM NAME="OutputFile"> forcesUpCyl </PARAM> > <PARAM NAME="OutputFrequency"> 10 </PARAM> > <PARAM NAME="Boundary"> B[3] </PARAM> > </FILTER> > </FILTERS> > > <GEOMETRY DIM="2" SPACE="2"> > <VERTEX COMPRESSED="B64Z-LittleEndian" BITSIZE="64"> > eJxtm3dgT9cbxr8SRCLIED+1d+0Zm9yrlBqNaM2qUZuiiqhSI2IlSI1WSKVUiYpYIcS8MWpTu2YJsXcUIcavbd73vfc+99x/XsnHOd/zfe5z3vPec09yurKutg2DPqmUVChFy3Xu29S1vjr92pXNZbtSNp0OH2Pl2SnuzxwYGXvO18HdKUYWeuI5/qpHCv0oHC4HzwH9I3eD/vHzPeD7Yftcto8v4/j+nsCxvReMv+oknwvb2xYVnhvGh9wbvh/yPDD+zUl9zlt5Xhgf8nw > > > On 9 Mar 2020, at 19:41, Sherwin, Spencer J <s.sherwin(a)imperial.ac.uk> > wrote: > > Hi Robin, > > Could you help Zhicheng with this request. > > Thanks, > Spencer. > > > On 5 Mar 2020, at 22:59, Wang, Zhicheng <zhicheng_wang(a)brown.edu> wrote: > > This email from zhicheng_wang(a)brown.edu originates from outside Imperial. > Do not click on links and attachments unless you recognise the sender. If > you trust the sender, add them to your safe senders list > <https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email > stamping for this address. > > Hi nektar++ users, > Is there anyone can give me a hint how to restart a simulation using the > VCSMapping solver ? > I see folders named *.chk and *.map, but how to use the *.map file to > restart a new simulation ? > > Best, > Zhicheng > _______________________________________________ > Nektar-users mailing list > Nektar-users(a)imperial.ac.uk > https://mailman.ic.ac.uk/mailman/listinfo/nektar-users > > > Spencer Sherwin FREng, FRAeS > Head of Aerodynamics Section, > Director of Research Computing Service, > Professor of Computational Fluid Mechanics, > Department of Aeronautics, > s.sherwin(a)imperial.ac.uk South > Kensington Campus, > Phone: +44 (0)20 7594 5052 Imperial College > London, > Fax: +44 (0)20 7594 1974 London, SW7 2AZ, > UK > http://www.imperial.ac.uk/people/s.sherwin/ > > >

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Restart using VCSMapping solver
by Wang, Zhicheng 09 Mar '20

09 Mar '20

******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hi nektar++ users, Is there anyone can give me a hint how to restart a simulation using the VCSMapping solver ? I see folders named *.chk and *.map, but how to use the *.map file to restart a new simulation ? Best, Zhicheng

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more on Building Nektar++ on Windows 10
by CARLOS LOZANO RODRIGUEZ 04 Mar '20

04 Mar '20

******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Dear all, I am trying to build Nektar 5.0.0 on windows 10. I am using vs 2019 and I have installed boost from boost_1_72_0-msvc-14.2-64.exe following advice from Jeremy Cohen https://mailman.ic.ac.uk/mailman/htdig/nektar-users/2020-March/001320.html I build scripts for Visual Studio 16 2019 and x64. cmake seems to correctly locate boost, the c++ compilers and everything else (configuration and generation run smoothly). I then issue msbuild INSTALL.vcxproj /p:Configuration=Release After a lenghty process, I get 7910 warnings and the following 6 errors (I apologize for it being in Spanish): "C:\nektar++-5.0.0\builds\INSTALL.vcxproj" (destino predeterminado) (1) -> "C:\nektar++-5.0.0\builds\ALL_BUILD.vcxproj" (destino predeterminado) (3) -> "C:\nektar++-5.0.0\builds\solvers\CardiacEPSolver\CardiacEPSolver-obj.vcxproj" (destino predeterminado) (4) -> "C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj" (destino predeterminado) (5) -> (ClCompile destino) -> C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(108,46): error C2065: '_TWO_DIGIT_EXPONENT': identificado r no declarado [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(108,27): error C3861: '_set_output_format': no se encontr ó el identificador [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(111,5): error C3861: '_set_output_format': no se encontró el identificador [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(169,46): error C2065: '_TWO_DIGIT_EXPONENT': identificado r no declarado [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(169,27): error C3861: '_set_output_format': no se encontr ó el identificador [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] C:\nektar++-5.0.0\library\SolverUtils\Core\CouplingFile.cpp(171,5): error C3861: '_set_output_format': no se encontró el identificador [C:\nektar++-5.0.0\builds\library\SolverUtils\SolverUtils.vcxproj] If I issue msbuild INSTALL.vcxproj /p:Configuration=Release again, I get just 10 warnings and still the same 6 errors any advice? Thanks a lot \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Carlos Lozano Rodríguez Área de Aerodinámica Teórica y Computacional / CFD Branch Instituto Nacional de Técnica Aeroespacial / National Institute for Aerospace Technology (INTA) Carretera Ajalvir km. 4 28850 Torrejón de Ardoz, Spain tel: +34 91 520 1908 e-mail: lozanorc(a)inta.es web: http://scholar.google.co.uk/citations?user=mrl2XhQAAAAJ

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Building Nektar++ on Windows 10
by Jeremy Cohen 02 Mar '20

02 Mar '20

Dear all, We're aware that there have been a few messages to the nektar-users list list recently regarding building on Windows 10. We've been investigating the issues and apologise where we've not been able to respond individually to these queries. Some updated instructions will appear in the Nektar++ user guide shortly for building on Windows 10 with recent versions of Visual Studio. In the meantime, we'd like to highlight that building Boost as a third party dependency as part of the Nektar++ build is not currently supported on Windows 10 with recent versions of Visual Studio. Instead you'll need to install the boost binaries from SourceForge and ensure that CMake correctly finds Boost during the configuration process. Instead of installing Boost 1.61 (as currently detailed in the user guide), if you're using Visual Studio 2017, we recommend that you install Boost 1.68 from https://sourceforge.net/projects/boost/files/boost-binaries/1.68.0/. For VS2017 on 64-bit Windows you should use the 14.1-64 installer - boost_1_68_0-msvc-14.1-64.exe. If you're using Visual Studio 2019, we recommend that you install Boost 1.72 from https://sourceforge.net/projects/boost/files/boost-binaries/1.72.0/. For VS2019 on 64-bit Windows you should use the 14.2-64 installer - boost_1_72_0-msvc-14.2-64.exe. Assuming that BOOST_HOME is set (as detailed in the current user guide) to the correct path for the location of the version of Boost that you have installed, configuring with CMake should find Boost successfully. Also note that you should run the cmake and msbuild commands within a Visual Studio command prompt. Assuming you're using a 64-bit version of Windows 10, this is the "x64 Native Tools Command Prompt for VS 2017" or "x64 Native Tools Command Prompt for VS 2019" for which there should be a shortcut in your Start menu. Rather than running the cmake-gui as detailed in the user guide, you should be able to use the command line cmake command to generate a standard Windows build configuration. You will need to specify the "Generator" to use when running cmake on the command line, e.g. 'cmake -G "Visual Studio 15 2017 Win64" ..' or 'cmake -G "Visual Studio 16 2019" ..' If you are still experiencing issues building Nektar++ under Windows 10, please continue to post any issues to the nektar-users list and we will try to assist in resolving build issues. Cheers, Jeremy

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Re: [Nektar-users] VIV flow past a cylinder
by Wang, Zhicheng 27 Feb '20

27 Feb '20

Vijay, thanks a lot. I have figured it out. I solve the oscillator equation in physical space and replace the newmark-beta scheme with the one we have in the old Nektar. now the displacement looks correct, please see the attached. On Thu, Feb 27, 2020 at 12:04 AM VIJAY KUSHWAHA <bijay8833(a)sjtu.edu.cn> wrote: > Hi Zhicheng, > 1. The structural stiffness parameter(StructStiff) is not defined in your > .xml file. Instead you have defined that term in cable tension. > 2. StructRho(m/rho*D^2) is the non-dimensional mass. For mass ratio to be > defined as 2.0, you need to define it accordingly. > Try with these parameters. > Cheers, > Vijay Kushwaha > > ----- Original Message ----- > From: "Wang, Zhicheng" <zhicheng_wang(a)brown.edu> > To: "ybao" <ybao(a)sjtu.edu.cn> > Cc: "Sherwin, Spencer J" <s.sherwin(a)imperial.ac.uk>, "nektar-users" < > nektar-users(a)imperial.ac.uk>, "Lahooti, Mohsen" <m.lahooti(a)imperial.ac.uk>, > "VIJAY KUSHWAHA" <bijay8833(a)sjtu.edu.cn> > Sent: Wednesday, February 26, 2020 11:16:52 PM > Subject: Re: [Nektar-users] VIV flow past a cylinder > > Hi Mohsen and Yan, thanks for your reply. Please find the amplitude and > lift coefficient are attached below. The lift coef looks reasonable. > Personally, I have done tons of similar simulations using the predecessor > SEM code Nektar, usually, VIV simulation is not sensitive to quadrature > points, aliasing error.... I will look at the code. Please let me know if > you get a chance to find out the mistakes in my parameter file. > > > On Wed, Feb 26, 2020 at 7:31 AM ybao <ybao(a)sjtu.edu.cn> wrote: > > > Hi Zhicheng, > > > > May you show me the time history of the cylinder vibration and lift > > coefficient for us? in NEKTAR++, the Euler beam model was employed to > > describe the vibration of the structure, so you need to check whether or > > not the values of tension, structure stiffness and bending stiffness are > > correct. recently Vijay, a graduate student in my group, have run 2D > > simulations and got correct results. > > > > Hi Vijay, can you have a look on the xml from Zhicheng? many thanks! > > > > Cheers, > > Yan > > > > On 26 Feb 2020, at 05:09, Wang, Zhicheng <zhicheng_wang(a)brown.edu> > wrote: > > > > Thank you Spencer. I will wait for Yan Bao or Mohsen's response. There > is > > no numerical instability issue for now, but thank you for the suggestion. > > > > On Tue, Feb 25, 2020 at 3:47 PM Sherwin, Spencer J < > > s.sherwin(a)imperial.ac.uk> wrote: > > > >> HI Zhicheng, > >> > >> I am forwarding your request to Yan Bao who is probably the most > >> experienced in this setup. Not sure if Yan is using the Nektar++ users > list > >> however. > >> > >> I would be inclined to use the SpectralVanishingViscosity with DGKernel > >> and Dealisasing if you get any flow instability issues. > >> > >> Cheers, > >> Spencer > >> > >> PS Mohsen might be able to help too. > >> > >> On 25 Feb 2020, at 15:05, Wang, Zhicheng <zhicheng_wang(a)brown.edu> > wrote: > >> > >> This email from zhicheng_wang(a)brown.edu originates from outside > >> Imperial. Do not click on links and attachments unless you recognise the > >> sender. If you trust the sender, add them to your safe senders list > >> <https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email > >> stamping for this address. > >> > >> Hi nektar++ users, > >> I wonder if there is anyone could check my simulation parameters for the > >> simulation of 2D vortex induced vibration (VIV) of flow past a cylinder > >> that is allowed to move in crossflow direction ? Here the cylinder is > >> rigidly mounted with a natural frequency f=0.17, mass per unit length > =2.0, > >> Re=100. For this particular case, the vibration amplitude is expected > to > >> be around 0.5D, but the simulation gave me 0.05D. So I think I must have > >> made some mistakes somewhere in the parameter file. The parameter file I > >> used is posted below. > >> > >> ****************************************************************** > >> <EXPANSIONS> > >> <E COMPOSITE="C[0]" BASISTYPE="Modified_A, Modified_A" > >> NUMMODES="3,3" POINTSTYPE="GaussLobattoLegendre, > >> GaussLobattoLegendre" > >> NUMPOINTS="5,5" FIELDS="u,v,w,p" /> > >> </EXPANSIONS> > >> > >> <CONDITIONS> > >> <SOLVERINFO> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> </SOLVERINFO> > >> > >> <PARAMETERS> > >> TimeStep = 0.005 > >> FinalTime = 1000 > >> NumSteps = FinalTime/TimeStep > >> IO_CheckSteps = 2000 > >> IO_InfoSteps = 25 > >> IO_CFLSteps = 25 > >> Re = 100 > >> > >> Kinvis = 1/Re > >> > >> HomModesZ = 2 > >> LZ = 0.01 > >> > >> FreqY = 0.17 > >> > >> OmegaY = 2.0*PI*FreqY > >> > >> StructStiff = 0.0 > >> > >> StructRho = 2.0 > > >> CableTension = OmegaY*OmegaY*StructRho > >> BendingStiff = 0.0 > > >> FictDamp = 1.0 > > >> FictMass = 1.5 > >> > >> </PARAMETERS> > >> > >> <VARIABLES> > >> <V ID="0"> u </V> > >> <V ID="1"> v </V> > >> <V ID="2"> w </V> > >> <V ID="3"> p </V> > >> </VARIABLES> > >> > >> <BOUNDARYREGIONS> > >> C[5]  > >> C[3]  > >> C[4]  > >> C[2]  > >> C[1]  > >> </BOUNDARYREGIONS> > >> > >> <BOUNDARYCONDITIONS> > >> <REGION REF="0"> > >> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > >> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> > >> <D VAR="w" VALUE="0" /> > >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > >> </REGION> > >> <REGION REF="1"> > >> > >> > >> > >> > >> </REGION> > >> <REGION REF="2"> > >> > >> > >> > >> > >> </REGION> > >> <REGION REF="3"> > >> <N VAR="u" VALUE="0" /> > >> <N VAR="v" VALUE="0" /> > >> <N VAR="w" VALUE="0" /> > >> <D VAR="p" VALUE="0" /> > >> </REGION> > >> <REGION REF="4"> > >> <D VAR="u" VALUE="1" /> > >> <D VAR="v" VALUE="0" /> > >> <D VAR="w" VALUE="0" /> > >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> > >> </REGION> > >> </BOUNDARYCONDITIONS> > >> > >> <FUNCTION NAME="InitialConditions"> > >> <E VAR="u" VALUE="0" /> > >> <E VAR="v" VALUE="0" /> > >> <E VAR="w" VALUE="0" /> > >> <E VAR="p" VALUE="0" /> > >> </FUNCTION> > >> > >> > >> <FUNCTION NAME="displacements"> > >> <E VAR="x" VALUE="0.0" /> > >> <E VAR="y" VALUE="A*cos(omega*t)*cos(2*PI*z/LZ)" /> > >> </FUNCTION> > >> <FUNCTION NAME="velocities"> > >> <E VAR="x" VALUE="0.0" /> > >> <E VAR="y" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" > /> > >> </FUNCTION> > >> <FUNCTION NAME="Mapping"> > >> <E VAR="x" VALUE="x" /> > >> <E VAR="y" VALUE="y+A*cos(omega*t)*cos(2*PI*z/LZ)" /> > >> </FUNCTION> > >> <FUNCTION NAME="MappingVel"> > >> <E VAR="vx" VALUE="0.0" /> > >> <E VAR="vy" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" > >> /> > >> </FUNCTION> > >> <FUNCTION NAME="accelerations"> > >> <E VAR="x" VALUE="0.0" /> > >> <E VAR="y" > >> VALUE="-1.0*omega*omega*A*cos(omega*t)*cos(2*PI*z/LZ)" /> > >> </FUNCTION> > >> > >> </CONDITIONS> > >> > >> <MAPPING TYPE="XYofZ"> > >> <COORDS>Mapping</COORDS> > >> <VEL>MappingVel</VEL> > >> <TIMEDEPENDENT>True</TIMEDEPENDENT> > >> </MAPPING> > >> > >> <FORCING> > >> <FORCE TYPE="MovingBody"> > >> <DISPLACEMENTS> displacements </DISPLACEMENTS> > >> <VELOCITIES> velocities </VELOCITIES> > >> <ACCELERATIONS> accelerations </ACCELERATIONS> > >> <PARAM NAME="OutputFile">TensionedCable</PARAM> > >> <PARAM NAME="OutputFrequency">25</PARAM> > >> <PARAM NAME="Boundary"> B[0] </PARAM> > >> </FORCE> > >> </FORCING> > >> > >> > **************************************************************************************** > >> Best Wishes, > >> Zhicheng Wang > >> _______________________________________________ > >> Nektar-users mailing list > >> Nektar-users(a)imperial.ac.uk > >> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users > >> > >> > >> Spencer Sherwin FREng, FRAeS > >> Head of Aerodynamics Section, > >> Director of Research Computing Service, > >> Professor of Computational Fluid Mechanics, > >> Department of Aeronautics, > >> s.sherwin(a)imperial.ac.uk South > >> Kensington Campus, > >> Phone: +44 (0)20 7594 5052 Imperial College > >> London, > >> Fax: +44 (0)20 7594 1974 London, SW7 > 2AZ, > >> UK > >> http://www.imperial.ac.uk/people/s.sherwin/ > >> > >> > >

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Re: [Nektar-users] VIV flow past a cylinder
by Wang, Zhicheng 26 Feb '20

26 Feb '20

Hi Mohsen and Yan, thanks for your reply. Please find the amplitude and lift coefficient are attached below. The lift coef looks reasonable. Personally, I have done tons of similar simulations using the predecessor SEM code Nektar, usually, VIV simulation is not sensitive to quadrature points, aliasing error.... I will look at the code. Please let me know if you get a chance to find out the mistakes in my parameter file. On Wed, Feb 26, 2020 at 7:31 AM ybao <ybao(a)sjtu.edu.cn> wrote: > Hi Zhicheng, > > May you show me the time history of the cylinder vibration and lift > coefficient for us? in NEKTAR++, the Euler beam model was employed to > describe the vibration of the structure, so you need to check whether or > not the values of tension, structure stiffness and bending stiffness are > correct. recently Vijay, a graduate student in my group, have run 2D > simulations and got correct results. > > Hi Vijay, can you have a look on the xml from Zhicheng? many thanks! > > Cheers, > Yan > > On 26 Feb 2020, at 05:09, Wang, Zhicheng <zhicheng_wang(a)brown.edu> wrote: > > Thank you Spencer. I will wait for Yan Bao or Mohsen's response. There is > no numerical instability issue for now, but thank you for the suggestion. > > On Tue, Feb 25, 2020 at 3:47 PM Sherwin, Spencer J < > s.sherwin(a)imperial.ac.uk> wrote: > >> HI Zhicheng, >> >> I am forwarding your request to Yan Bao who is probably the most >> experienced in this setup. Not sure if Yan is using the Nektar++ users list >> however. >> >> I would be inclined to use the SpectralVanishingViscosity with DGKernel >> and Dealisasing if you get any flow instability issues. >> >> Cheers, >> Spencer >> >> PS Mohsen might be able to help too. >> >> On 25 Feb 2020, at 15:05, Wang, Zhicheng <zhicheng_wang(a)brown.edu> wrote: >> >> This email from zhicheng_wang(a)brown.edu originates from outside >> Imperial. Do not click on links and attachments unless you recognise the >> sender. If you trust the sender, add them to your safe senders list >> <https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email >> stamping for this address. >> >> Hi nektar++ users, >> I wonder if there is anyone could check my simulation parameters for the >> simulation of 2D vortex induced vibration (VIV) of flow past a cylinder >> that is allowed to move in crossflow direction ? Here the cylinder is >> rigidly mounted with a natural frequency f=0.17, mass per unit length =2.0, >> Re=100. For this particular case, the vibration amplitude is expected to >> be around 0.5D, but the simulation gave me 0.05D. So I think I must have >> made some mistakes somewhere in the parameter file. The parameter file I >> used is posted below. >> >> ****************************************************************** >> <EXPANSIONS> >> <E COMPOSITE="C[0]" BASISTYPE="Modified_A, Modified_A" >> NUMMODES="3,3" POINTSTYPE="GaussLobattoLegendre, >> GaussLobattoLegendre" >> NUMPOINTS="5,5" FIELDS="u,v,w,p" /> >> </EXPANSIONS> >> >> <CONDITIONS> >> <SOLVERINFO> >> >> >> >> >> >> >> >> >> >> >> >> >> </SOLVERINFO> >> >> <PARAMETERS> >> TimeStep = 0.005 >> FinalTime = 1000 >> NumSteps = FinalTime/TimeStep >> IO_CheckSteps = 2000 >> IO_InfoSteps = 25 >> IO_CFLSteps = 25 >> Re = 100 >> >> Kinvis = 1/Re >> >> HomModesZ = 2 >> LZ = 0.01 >> >> FreqY = 0.17 >> >> OmegaY = 2.0*PI*FreqY >> >> StructStiff = 0.0 >> >> StructRho = 2.0 >> CableTension = OmegaY*OmegaY*StructRho >> BendingStiff = 0.0 >> FictDamp = 1.0 >> FictMass = 1.5 >> >> </PARAMETERS> >> >> <VARIABLES> >> <V ID="0"> u </V> >> <V ID="1"> v </V> >> <V ID="2"> w </V> >> <V ID="3"> p </V> >> </VARIABLES> >> >> <BOUNDARYREGIONS> >> C[5]  >> C[3]  >> C[4]  >> C[2]  >> C[1]  >> </BOUNDARYREGIONS> >> >> <BOUNDARYCONDITIONS> >> <REGION REF="0"> >> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> >> <D VAR="w" VALUE="0" /> >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> >> </REGION> >> <REGION REF="1"> >> >> >> >> >> </REGION> >> <REGION REF="2"> >> >> >> >> >> </REGION> >> <REGION REF="3"> >> <N VAR="u" VALUE="0" /> >> <N VAR="v" VALUE="0" /> >> <N VAR="w" VALUE="0" /> >> <D VAR="p" VALUE="0" /> >> </REGION> >> <REGION REF="4"> >> <D VAR="u" VALUE="1" /> >> <D VAR="v" VALUE="0" /> >> <D VAR="w" VALUE="0" /> >> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> >> </REGION> >> </BOUNDARYCONDITIONS> >> >> <FUNCTION NAME="InitialConditions"> >> <E VAR="u" VALUE="0" /> >> <E VAR="v" VALUE="0" /> >> <E VAR="w" VALUE="0" /> >> <E VAR="p" VALUE="0" /> >> </FUNCTION> >> >> >> <FUNCTION NAME="displacements"> >> <E VAR="x" VALUE="0.0" /> >> <E VAR="y" VALUE="A*cos(omega*t)*cos(2*PI*z/LZ)" /> >> </FUNCTION> >> <FUNCTION NAME="velocities"> >> <E VAR="x" VALUE="0.0" /> >> <E VAR="y" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" /> >> </FUNCTION> >> <FUNCTION NAME="Mapping"> >> <E VAR="x" VALUE="x" /> >> <E VAR="y" VALUE="y+A*cos(omega*t)*cos(2*PI*z/LZ)" /> >> </FUNCTION> >> <FUNCTION NAME="MappingVel"> >> <E VAR="vx" VALUE="0.0" /> >> <E VAR="vy" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" >> /> >> </FUNCTION> >> <FUNCTION NAME="accelerations"> >> <E VAR="x" VALUE="0.0" /> >> <E VAR="y" >> VALUE="-1.0*omega*omega*A*cos(omega*t)*cos(2*PI*z/LZ)" /> >> </FUNCTION> >> >> </CONDITIONS> >> >> <MAPPING TYPE="XYofZ"> >> <COORDS>Mapping</COORDS> >> <VEL>MappingVel</VEL> >> <TIMEDEPENDENT>True</TIMEDEPENDENT> >> </MAPPING> >> >> <FORCING> >> <FORCE TYPE="MovingBody"> >> <DISPLACEMENTS> displacements </DISPLACEMENTS> >> <VELOCITIES> velocities </VELOCITIES> >> <ACCELERATIONS> accelerations </ACCELERATIONS> >> <PARAM NAME="OutputFile">TensionedCable</PARAM> >> <PARAM NAME="OutputFrequency">25</PARAM> >> <PARAM NAME="Boundary"> B[0] </PARAM> >> </FORCE> >> </FORCING> >> >> **************************************************************************************** >> Best Wishes, >> Zhicheng Wang >> _______________________________________________ >> Nektar-users mailing list >> Nektar-users(a)imperial.ac.uk >> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users >> >> >> Spencer Sherwin FREng, FRAeS >> Head of Aerodynamics Section, >> Director of Research Computing Service, >> Professor of Computational Fluid Mechanics, >> Department of Aeronautics, >> s.sherwin(a)imperial.ac.uk South >> Kensington Campus, >> Phone: +44 (0)20 7594 5052 Imperial College >> London, >> Fax: +44 (0)20 7594 1974 London, SW7 2AZ, >> UK >> http://www.imperial.ac.uk/people/s.sherwin/ >> >> >

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Re: [Nektar-users] NekMesh Error in Converting the MSH in Nektar++ format
by Silvia Ceccacci (HDR) 26 Feb '20

26 Feb '20

Hi Dave, Thank you for your reply. I’m using the latest one (v5.0.0). Many thanks, Silvia Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: Moxey, David <D.Moxey(a)exeter.ac.uk> Sent: Wednesday, February 26, 2020 8:55:46 PM To: Silvia Ceccacci (HDR) <silvia.ceccacci(a)hdr.mq.edu.au> Cc: nektar-users(a)imperial.ac.uk <nektar-users(a)imperial.ac.uk> Subject: Re: [Nektar-users] NekMesh Error in Converting the MSH in Nektar++ format Hi Silvia, Could I ask what version of Nektar++ you're using? The MSH format changed somewhat recently, so the reader for this is in our latest release (v5.0.0). Many thanks, Dave > On 26 Feb 2020, at 04:34, Silvia Ceccacci (HDR) <silvia.ceccacci(a)hdr.mq.edu.au> wrote: > > This email from silvia.ceccacci(a)hdr.mq.edu.au originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list to disable email stamping for this address. > > Dear all, > > This is Silvia Ceccacci from Macquarie University, Sydney. I am a new PhD student in Mathematics and I have just started to use Nektar++ to perform 3D incompressible N-S simulations. > > I am exporting a mesh from gmsh and I am trying to simulate a flow around a sphere. So I would like to generate the 3D mesh within the main domain with the sphere taken out (see sphere_2.geo). I managed to generate the .msh file (see sphere_2.msh), using the command line > > gmsh -3 -order 3 sphere_2.geo > > but now I get an error (see error.png) when I issue > > NekMesh sphere_2.msh sphere_2.xml > > I am not sure what the error means and/or what am I doing wrong? Could you help me with this, please? > > Any little help or suggestion would be greatly appreciated. > > Thank you in advance. > > Kind regards, > Silvia > > > <sphere.zip>_______________________________________________ > Nektar-users mailing list > Nektar-users(a)imperial.ac.uk > https://mailman.ic.ac.uk/mailman/listinfo/nektar-users<https://mailman.ic.ac.uk/mailman/listinfo/nektar-users> -- Dr David Moxey, PhD MMath MIMA FHEA Senior Lecturer in Engineering d.moxey(a)exeter.ac.uk | tel: 01392 724764 | web: davidmoxey.uk Room 1.24, Hope Hall, University of Exeter, Exeter, EX4 4PL, UK.

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NekMesh Error in Converting the MSH in Nektar++ format
by Silvia Ceccacci (HDR) 26 Feb '20

26 Feb '20

******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Dear all, This is Silvia Ceccacci from Macquarie University, Sydney. I am a new PhD student in Mathematics and I have just started to use Nektar++ to perform 3D incompressible N-S simulations. I am exporting a mesh from gmsh and I am trying to simulate a flow around a sphere. So I would like to generate the 3D mesh within the main domain with the sphere taken out (see sphere_2.geo). I managed to generate the .msh file (see sphere_2.msh), using the command line gmsh -3 -order 3 sphere_2.geo but now I get an error (see error.png) when I issue NekMesh sphere_2.msh sphere_2.xml I am not sure what the error means and/or what am I doing wrong? Could you help me with this, please? Any little help or suggestion would be greatly appreciated. Thank you in advance. Kind regards, Silvia

1 0

VIV flow past a cylinder
by Wang, Zhicheng 25 Feb '20

25 Feb '20

******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hi nektar++ users, I wonder if there is anyone could check my simulation parameters for the simulation of 2D vortex induced vibration (VIV) of flow past a cylinder that is allowed to move in crossflow direction ? Here the cylinder is rigidly mounted with a natural frequency f=0.17, mass per unit length =2.0, Re=100. For this particular case, the vibration amplitude is expected to be around 0.5D, but the simulation gave me 0.05D. So I think I must have made some mistakes somewhere in the parameter file. The parameter file I used is posted below. ****************************************************************** <EXPANSIONS> <E COMPOSITE="C[0]" BASISTYPE="Modified_A, Modified_A" NUMMODES="3,3" POINTSTYPE="GaussLobattoLegendre, GaussLobattoLegendre" NUMPOINTS="5,5" FIELDS="u,v,w,p" /> </EXPANSIONS> <CONDITIONS> <SOLVERINFO> </SOLVERINFO> <PARAMETERS> TimeStep = 0.005 FinalTime = 1000 NumSteps = FinalTime/TimeStep IO_CheckSteps = 2000 IO_InfoSteps = 25 IO_CFLSteps = 25 Re = 100 Kinvis = 1/Re HomModesZ = 2 LZ = 0.01 FreqY = 0.17 OmegaY = 2.0*PI*FreqY StructStiff = 0.0 StructRho = 2.0 CableTension = OmegaY*OmegaY*StructRho BendingStiff = 0.0 FictDamp = 1.0 FictMass = 1.5 </PARAMETERS> <VARIABLES> <V ID="0"> u </V> <V ID="1"> v </V> <V ID="2"> w </V> <V ID="3"> p </V> </VARIABLES> <BOUNDARYREGIONS> C[5]  C[3]  C[4]  C[2]  C[1]  </BOUNDARYREGIONS> <BOUNDARYCONDITIONS> <REGION REF="0"> <D VAR="u" USERDEFINEDTYPE="MovingBody" VALUE="0" /> <D VAR="v" USERDEFINEDTYPE="MovingBody" VALUE="0" /> <D VAR="w" VALUE="0" /> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> </REGION> <REGION REF="1"> </REGION> <REGION REF="2"> </REGION> <REGION REF="3"> <N VAR="u" VALUE="0" /> <N VAR="v" VALUE="0" /> <N VAR="w" VALUE="0" /> <D VAR="p" VALUE="0" /> </REGION> <REGION REF="4"> <D VAR="u" VALUE="1" /> <D VAR="v" VALUE="0" /> <D VAR="w" VALUE="0" /> <N VAR="p" USERDEFINEDTYPE="H" VALUE="0" /> </REGION> </BOUNDARYCONDITIONS> <FUNCTION NAME="InitialConditions"> <E VAR="u" VALUE="0" /> <E VAR="v" VALUE="0" /> <E VAR="w" VALUE="0" /> <E VAR="p" VALUE="0" /> </FUNCTION> <FUNCTION NAME="displacements"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="A*cos(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="velocities"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="Mapping"> <E VAR="x" VALUE="x" /> <E VAR="y" VALUE="y+A*cos(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="MappingVel"> <E VAR="vx" VALUE="0.0" /> <E VAR="vy" VALUE="-1.0*omega*A*sin(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> <FUNCTION NAME="accelerations"> <E VAR="x" VALUE="0.0" /> <E VAR="y" VALUE="-1.0*omega*omega*A*cos(omega*t)*cos(2*PI*z/LZ)" /> </FUNCTION> </CONDITIONS> <MAPPING TYPE="XYofZ"> <COORDS>Mapping</COORDS> <VEL>MappingVel</VEL> <TIMEDEPENDENT>True</TIMEDEPENDENT> </MAPPING> <FORCING> <FORCE TYPE="MovingBody"> <DISPLACEMENTS> displacements </DISPLACEMENTS> <VELOCITIES> velocities </VELOCITIES> <ACCELERATIONS> accelerations </ACCELERATIONS> <PARAM NAME="OutputFile">TensionedCable</PARAM> <PARAM NAME="OutputFrequency">25</PARAM> <PARAM NAME="Boundary"> B[0] </PARAM> </FORCE> </FORCING> **************************************************************************************** Best Wishes, Zhicheng Wang

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