dear all, i've try to simulate a local scour around a pier with sediment model build in FLUIDITY. subgridscale parameterisations/kepsilon is be used and kepsilon boundary is be applied to bottom and pier sides.but the "TurbulentDissipation" around the pier surface would increase greatly with time. I've try to turn off sediment model, or modify the grid resolution and background viscosity but still can't let "TurbulentDissipation" stable. any comment is appreciated. thanks. # box set Length:0.36 m Width:0.36 m Height:0.07 m radius(pier):0.03 m # velocity boundary west : a constant velocity 0.2 m/s (inlet) east : zero-gradient boundary conditions (outlet) south and north : free slide wall top : free surface bottom : no normal flow and drag pier : no normal flow the geo and flml content is attached below. # --- pier_scour.geo --- rad = 0.03; //0.03 d1=0.03; //0.03 d3=0.01; //0.01 len=0.36; //0.36 wid=0.36; //0.36 Point(1) = {-0.5*len, -0.5*wid, 0, d1}; Point(2) = { 0.5*len, -0.5*wid, 0, d1}; Point(3) = { 0.5*len, 0.5*wid, 0, d1}; Point(4) = {-0.5*len, 0.5*wid, 0, d1}; Line(1) = {1, 2}; Line(2) = {2, 3}; Line(3) = {3, 4}; Line(4) = {4, 1}; Point(5) = {0, 0, 0, d3}; Point(6) = {0, 0+rad, 0, d3}; Point(7) = {0+rad, 0, 0, d3}; Point(8) = {0, 0-rad, 0, d3}; Point(9) = {0-rad, 0, 0, d3}; Circle(5) = {6, 5, 7}; Circle(6) = {7, 5, 8}; Circle(7) = {8, 5, 9}; Circle(8) = {9, 5, 6}; Line Loop(13) = {1,2,3,4}; Line Loop(14) = {5,6,7,8}; Plane Surface(15) = {13,14}; //Plane Surface(8) = {13}; Physical Line(7) = {1}; //S Physical Line(8) = {2}; //E Physical Line(9) = {3}; //N Physical Line(10) = {4}; //W Physical Line(11) = {5,6,7,8}; //pier Physical Surface(12) = {15}; # --- pier_scour.flml --- pier_scour fluids 3 1 1 discontinuous 2 0.07 0.07 0.01 307 308 4 4 307 308 vtk def val(t): if t<2.5: return 0.25 elif t<20: return 1.0 else: return 5.0 100 0 0.005 7200 2 9.81 0 0 -1 1

0 0.5 3 30 1e-07 6001 0 11 308 low_Re 0 0.5 3 30 1e-07 6002 0 11 308 low_Re 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 10 def val(X,t): xc=0.0 # x at circile center yc=0.0 # y at circile center rad=0.03 # radius 0.03 dep=0.07 # depth 0.07 val=((X[0]-xc)**2+(X[1]-yc)**2)**0.5 - rad # if more close to bottom if val>(dep+X[2]): val=dep+X[2] if val<0: val=0 return val 0.09 1.44 1.92 1 1.3 1 0.5 source absorbtion source

never 1e-07 3000 0 1 1 0.1 30 1e-07 10000 0 0 0 308 0.0025 0.0025 307 11 308 10 0.2 def val(X,t): amp=0.5 if (t<10): val=amp*t/10 else: val=amp return val 7 9 0 1000 0.0025 2.5e-3 0 0.5 3 30 1e-07 2000 0 308 Garcia_1991 7 9 10 11 307 8 0 1e-10 308 0 0.5 3 30 1e-07 1000 0.04 0.0133 0.014 1.69 1.65 0.00107 0.000125 0.3 1 308 308 0.001

When	Who	Action	New State
2014-01-02	Jon Hill	Answer	Answered
2014-01-03	Samuel Parkinson	Answer	Answered
2014-01-06	liu chin chi	Reopen	Open
2014-01-06	Samuel Parkinson	Answer	Answered
2014-01-08	liu chin chi	Comment	Answered
2014-01-14	liu chin chi	Confirm	Solved
2014-01-14	liu chin chi	Confirm	Solved

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