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>

            <I PROPERTY="SolverType"            VALUE="VCSMapping" />

            <I PROPERTY="EQTYPE"                VALUE="UnsteadyNavierStokes" />

            <I PROPERTY="EvolutionOperator"     VALUE="Nonlinear" />

            <I PROPERTY="Projection"            VALUE="Galerkin" />

            <I PROPERTY="GlobalSysSoln"         VALUE="XxtMultiLevelStaticCond"/>

            <I PROPERTY="TimeIntegrationMethod" VALUE="IMEXOrder1" />

            <I PROPERTY="MappingImplicitPressure" VALUE="True" />

            <I PROPERTY="MappingImplicitViscous"  VALUE="True" />

        </SOLVERINFO>

        <PARAMETERS>

            <P> TimeStep      = 0.004           </P>

            <P> T             = 40              </P>

            <P> NumSteps      = T/TimeStep     </P>

            <P> IO_CheckSteps = NumSteps/200    </P>

            <P> IO_InfoSteps  = 10              </P>

            <P> IO_CFLSteps   = 10              </P>

            <P> Re            = 150             </P>

            <P> Kinvis        = 1/Re            </P>

            <P> forcedAmplitudeY      = 0.5             </P>

            <P> forcedAmplitudeX      = 0.2*forcedAmplitudeY </P>

            <P> forcedFreqY           = 1.5*0.2         </P>

            <P> forcedFreqX           = 2*forcedFreqY   </P>

            <P> MappingPressureTolerance  = 1e-6  </P>

            <P> MappingViscousTolerance   = 1e-8  </P>

            <P> MappingPressureRelaxation = 0.4  </P>

            <P> MappingViscousRelaxation  = 0.4  </P>

            <!-- Structural parameters -->

            <P> Mr     = 4.0  </P>

            <P> Cr     = 0.007  </P>

            <P> Vr     = 10.0  </P>

            <P> fn     = 1.0/Vr </P>

            <P> M      = Mr * PI / 4.0   </P>

            <P> K      = M* ( 2*PI *fn ) * ( 2*PI *fn )  </P>

            <P> C      = Cr * 2 * sqrt(K*M)   </P>

        </PARAMETERS>

        <VARIABLES>

            <V ID="0"> u </V>

            <V ID="1"> v </V>

            <V ID="2"> p </V>

        </VARIABLES>

        <BOUNDARYREGIONS>

            <B ID="0"> C[125-126] </B>    <!-- Downstream cylinder -->

            <B ID="1"> C[120-121] </B>    <!-- Far Field -->

            <B ID="2"> C[122] </B>        <!-- Outlet -->

            <B ID="3"> C[123-124] </B>    <!-- Upstream cylinder -->

        </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@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@brown.edu> wrote:

This email from zhicheng_wang@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 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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Spencer Sherwin FREng, FRAeS
Head of Aerodynamics Section,
Director of Research Computing Service,
Professor of Computational Fluid Mechanics,
Department of Aeronautics,
s.sherwin@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/