[MITgcm-support] Modeling of the surface waves

[王刚]

Dear all,

     I try to simulate the surface gravity waves in a small  water tank using non-hydrostatic model. The eastern boundary is sponge layers, and western boundary is prescribed periodical changing U and W. They are sinusoidal or cosinusoidal waves exponentially decayed with depth  [U=a*c*k*exp(k*z)*cos(k*x-sigma*t   and  w=-a*c*k*exp(k*z)*sin(k*x-sigma*t),   where  a=0.2m is the amplitude of sea lever，c=2m/s  is the phase velocity，k=2*pi/10m wavenumber，z=12.6m depth，sigma frequency]. However, the eta (sea surface lever) is very small (almost zero) in my result, and I can not find any clue of surface waves. Did I set wrong perameters?

. The following are my data 

# Continuous equation parameters
 &PARM01
 tRef =100*20,  
 sRef = 100*10,
 f0=0,           
 viscAz=1.0E-6,
 viscAh=1.0E-6,
 no_slip_sides=.FALSE.,
 no_slip_bottom=.FALSE.,
 viscA4=0.E12,
 diffKhT=1.44E-7,
 diffKzT=1.44E-7,
#diffK4T=5.E3,
 diffKhS=1.44E-7,
 diffKzS=1.44E-7,
 beta=0.E-11,
 tAlpha=2.E-4,    
 sBeta =7.4E-4,
 gravity=9.81,
 gBaro=9.81,
 rigidLid=.FALSE.,
 nonHydrostatic=.TRUE.,
 implicitFreeSurface=.TRUE.,
 eosType='LINEAR',
 readBinaryPrec=64,
#- not safe to use globalFiles in multi-processors runs
#globalFiles=.TRUE.,
 writeBinaryPrec=64,
 writeStatePrec=64,
#saltStepping=.FALSE.,
 hFacMin=0.1,
 implicSurfPress=0.5,
 implicDiv2DFlow=0.5,
#nonlinFreeSurf=3,
#hFacInf=0.2,
#hFacSup=2.0,
 exactConserv=.TRUE.
 &

# Elliptic solver parameters
 &PARM02
 cg2dMaxIters=1000,
 cg2dTargetResidual=1.E-10,
 cg3dMaxIters=100,
 cg3dTargetResidual=1.E-10,
 &

# Time stepping parameters
 &PARM03
 niter0=0,
 nTimeSteps=250000,
 deltaT=0.02,
 deltaTtracer=0.02,
 abEps=0.0001,
 pChkptFreq=500,
 chkptFreq=500,
 dumpFreq=1,
 monitorFreq=0.1,
 periodicExternalForcing=.TRUE.,
 externForcingPeriod=0.02,
 externForcingCycle=5,
 &

# Gridding parameters
 &PARM04
 usingCartesianGrid=.TRUE.,
 usingSphericalPolarGrid=.FALSE.,
 delX=1000*0.5,
 delY=5,
 delZ=10*0.05,10*0.06,10*0.07,10*0.08,10*0.1,10*0.12,10*0.15,10*0.18,10*0.2,10*0.25,
&

# Input datasets
 &PARM05
 hydrogThetaFile='T.init',
#hydrogSaltFile='S.init',
 bathyFile='topog',
 &


  , and data.obcs  

        
# Open-boundaries
 &OBCS_PARM01
 OB_Ieast=-1,
 OB_Iwest=1,
 useOrlanskiEast =.TRUE.,
 useOrlanskiWest =.FALSE.,
 useOBCSbalance=.TRUE.,
 useOBCSprescribe=.TRUE.,
#useOBCSsponge=.TRUE.,
#OBEuFile='uEast.bin',
 OBWuFile='uWest.bin',
#OBWwFile='wWest.bin',
#OBWetaFile='etaWest.bin',
&

&OBCS_PARM02
 cmax=0.45D0,
 cvelTimeScale=5.D0,
&
 
# *****************************************
# Sponge Layer Parameters.
# *****************************************
 &OBCS_PARM03
# Urelaxobcsinner  = 0,
#Urelaxobcsbound  = 5,
#spongeThickness  = 20,
 &
# end of the parameters.
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