id summary reporter owner description type status priority milestone component version resolution keywords cc 5800 OMEdit fails to simulate example model from OpenHPL Dietmar Winkler Per Östlund "When testing some of the examples of https://github.com/simulatino/OpenHPL I got the following error message which I don't really know how to tackle. This happens when running `OpenHPL.Examples.HPSimple`: : {{{ [3] 14:08:06 Translation Error Internal error IndexReduction.pantelidesIndexReduction failed! System is structurally singulare and cannot handled because number of unassigned equations is larger than number of states. Use -d=bltdump to get more information. }}} So I did set the flag and got: {{{ [2] 14:08:06 Symbolic Error [OpenHPL.Waterway.SurgeTank: 119:3-119:16]: Model is structurally singular, error found sorting equations 36: surgeTank.Mdot = surgeTank.mdot * surgeTank.v 34: surgeTank.M = surgeTank.m * surgeTank.v 39: surgeTank.F_g = surgeTank.m * data.g * surgeTank.cos_theta 38: surgeTank.F_p = (surgeTank.p_n - data.p_a) * surgeTank.A 30: der(surgeTank.M) = surgeTank.Mdot + surgeTank.F 22: der(tail.m) = 0.0 18: tail.A = tail.H * (tail.w + 2.0 * tail.H * tan(0.0174532925199433 * tail.alpha)) 20: tail.F_f = 0.0 19: tail.m = data.rho * tail.A * tail.L 14: discharge.v = discharge.Vdot / discharge.A_ 13: discharge.Vdot = turbine.mdot / data.rho 21: 0.0 = tail.A * (data.p_a - discharge.p_o) + data.g * data.rho * tail.A * tail.H - tail.F_f 15: discharge.M = data.rho * discharge.L * discharge.Vdot 16: discharge.F_f = OpenHPL.Functions.DarcyFriction.Friction(discharge.v, discharge.D_, discharge.L, data.rho, data.mu, discharge.p_eps) 7: turbine.look_up_table.u[1] = control.offset + (if time < control.startTime then 0.0 else if time < control.startTime + control.duration then (time - control.startTime) * control.height / control.duration else control.height) 42: turbine.Vdot = if turbine.WaterCompress then turbine.mdot / (data.rho * (1.0 + data.beta * (turbine.p_i_tr - data.p_a))) else turbine.mdot / data.rho 17: der(discharge.M) = data.rho * discharge.Vdot ^ 2.0 * (1.0 / discharge.A_i + (-1.0) / discharge.A_o) + turbine.p_o_tr * discharge.A_i + discharge.m * data.g * discharge.cos_theta + (-discharge.F_f) - discharge.p_o * discharge.A_o 43: turbine.dp = turbine.Vdot ^ 2.0 * data.p_a / (turbine.C_v_ * turbine.look_up_table.u[1]) ^ 2.0 5: der(reservoir.m) = 0.0 1: reservoir.A = reservoir.H * (reservoir.w + 2.0 * reservoir.H * tan(0.0174532925199433 * reservoir.alpha)) 3: reservoir.F_f = 0.0 2: reservoir.m = data.rho * reservoir.A * reservoir.L 9: intake.v = intake.Vdot / intake.A_ 4: 0.0 = reservoir.A * (data.p_a - intake.p_i) + data.g * data.rho * reservoir.A * reservoir.H - reservoir.F_f 10: intake.M = data.rho * intake.L * intake.Vdot 11: intake.F_f = OpenHPL.Functions.DarcyFriction.Friction(intake.v, intake.D_, intake.L, data.rho, data.mu, intake.p_eps) 25: penstock.v = penstock.Vdot / penstock.A_ 44: turbine.dp = turbine.p_i_tr - turbine.p_o_tr 12: der(intake.M) = data.rho * intake.Vdot ^ 2.0 * (1.0 / intake.A_i + (-1.0) / intake.A_o) + intake.p_i * intake.A_i + intake.m * data.g * intake.cos_theta + (-intake.F_f) - surgeTank.p_n * intake.A_o 27: penstock.F_f = OpenHPL.Functions.DarcyFriction.Friction(penstock.v, penstock.D_, penstock.L, data.rho, data.mu, penstock.p_eps) 28: der(penstock.M) = data.rho * penstock.Vdot ^ 2.0 * (1.0 / penstock.A_i + (-1.0) / penstock.A_o) + surgeTank.p_n * penstock.A_i + penstock.m * data.g * penstock.cos_theta + (-penstock.F_f) - turbine.p_i_tr * penstock.A_o 26: penstock.M = data.rho * penstock.L * penstock.Vdot 6: intake.Vdot = data.rho 24: penstock.Vdot = turbine.mdot / data.rho 8: intake.Vdot = intake.mdot / data.rho 40: surgeTank.mdot = intake.mdot - turbine.mdot 33: surgeTank.mdot = data.rho * surgeTank.Vdot 37: surgeTank.F = surgeTank.F_p + (-surgeTank.F_f) - surgeTank.F_g 35: surgeTank.v = surgeTank.Vdot / surgeTank.A 29: der(surgeTank.m) = surgeTank.mdot 32: surgeTank.F_f = OpenHPL.Functions.DarcyFriction.Friction(surgeTank.v, surgeTank.D, surgeTank.l, data.rho, data.mu, surgeTank.p_eps) 31: surgeTank.m = data.rho * surgeTank.A * surgeTank.l for variables 20: surgeTank.Mdot:VARIABLE(unit = ""N"" ) ""Difference in influent and effulent momentum""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 21: surgeTank.M:STATE(1)(unit = ""kg.m/s"" ) ""Water momuntum""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 14: surgeTank.F_g:VARIABLE(unit = ""N"" ) ""Gravity force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 16: surgeTank.F_p:VARIABLE(unit = ""N"" ) ""Pressure force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 19: surgeTank.F:VARIABLE(unit = ""N"" ) ""Total force acting in the surge tank""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 31: tail.m:STATE(1)(min = 0.0 unit = ""kg"" ) ""water mass""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 28: tail.H:VARIABLE(min = 0.0 unit = ""m"" ) ""water height""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 29: tail.F_f:VARIABLE(unit = ""N"" ) ""friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 32: tail.A:VARIABLE(unit = ""m2"" ) ""vertiacal cross section""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 38: discharge.v:VARIABLE(unit = ""m/s"" ) ""Water velocity""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 33: discharge.Vdot:VARIABLE(start = discharge.Vdot_0 unit = ""m3/s"" ) ""Flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 35: discharge.p_o:VARIABLE(unit = ""Pa"" ) ""Outlet pressure""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 36: discharge.M:STATE(1)(unit = ""kg.m/s"" ) ""Water momentum""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 37: discharge.F_f:VARIABLE(unit = ""N"" ) ""Friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 2: turbine.look_up_table.u[1]:VARIABLE(flow=false ) ""Connector of Real input signals""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine, Modelica.Blocks.Tables.CombiTable1D type: Real [1] 5: turbine.Vdot:VARIABLE(unit = ""m3/s"" ) ""Flow rate""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine type: Real 7: turbine.p_o_tr:VARIABLE(unit = ""Pa"" ) ""Outlet pressure""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine type: Real 8: turbine.dp:VARIABLE(unit = ""Pa"" ) ""Turbine pressure drop""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine type: Real 49: reservoir.m:STATE(1)(min = 0.0 unit = ""kg"" ) ""water mass""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 46: reservoir.H:VARIABLE(min = 0.0 unit = ""m"" ) ""water height""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 47: reservoir.F_f:VARIABLE(unit = ""N"" ) ""friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 50: reservoir.A:VARIABLE(unit = ""m2"" ) ""vertiacal cross section""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real 45: intake.v:VARIABLE(unit = ""m/s"" ) ""Water velocity""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 42: intake.p_i:VARIABLE(unit = ""Pa"" ) ""Inlet pressure""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 43: intake.M:STATE(1)(unit = ""kg.m/s"" ) ""Water momentum""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 44: intake.F_f:VARIABLE(unit = ""N"" ) ""Friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 27: penstock.v:VARIABLE(unit = ""m/s"" ) ""Water velocity""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 9: turbine.p_i_tr:VARIABLE(unit = ""Pa"" ) ""Inlet pressure""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine type: Real 11: surgeTank.p_n:VARIABLE(unit = ""Pa"" ) ""Node pressure""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 26: penstock.F_f:VARIABLE(unit = ""N"" ) ""Friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 25: penstock.M:STATE(1)(unit = ""kg.m/s"" ) ""Water momentum""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 23: penstock.Vdot:VARIABLE(start = penstock.Vdot_0 unit = ""m3/s"" ) ""Flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 40: intake.Vdot:VARIABLE(start = intake.Vdot_0 unit = ""m3/s"" ) ""Flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 3: turbine.mdot:VARIABLE(unit = ""kg/s"" ) ""Mass flow rate""OpenHPL.Examples.HPSimple, OpenHPL.ElectroMech.Turbines.Turbine type: Real 39: intake.mdot:VARIABLE(unit = ""kg/s"" ) ""Mass flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Pipe type: Real 10: surgeTank.mdot:VARIABLE(unit = ""kg/s"" ) ""Mass flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 12: surgeTank.Vdot:VARIABLE(start = surgeTank.Vdot_0 unit = ""m3/s"" fixed = true ) ""Water flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 15: surgeTank.F_f:VARIABLE(unit = ""N"" ) ""Friction force""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 17: surgeTank.v:VARIABLE(unit = ""m/s"" ) ""Water velocity""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 22: surgeTank.m:STATE(1,surgeTank.mdot)(min = 0.0 unit = ""kg"" ) ""Water mass""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 18: surgeTank.l:VARIABLE(unit = ""m"" ) ""Length of water in the surge tank""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.SurgeTank type: Real 48: reservoir.Vdot_i:VARIABLE(unit = ""m3/s"" ) ""inlet flow rate""OpenHPL.Examples.HPSimple, OpenHPL.Waterway.Reservoir type: Real [3] 14:08:06 Translation Error Internal error Transformation Module PFPlusExt index Reduction Method Pantelides failed! }}} I'm not really sure what is missing here especially since the component that OM is complaining about `OpenHPL.Waterway.SurgeTank` is also used in `OpenHPL.Examples.HPSimple_Francis` which works perfectly fine. Needless to say that I did test in Dymola before reporting and there no problem occurs what so ever. " defect assigned high Backend v1.16.0-dev