Modelica中的Sweptvolume组件内的压力

Question

我在Modelica中模拟了一个系统，在这个系统中，流体应该从4巴压缩到500巴。我给出了4巴入口压力和500巴出口压力作为边界条件。我想通过活塞的运动来实现这种压缩。当出口压力定义为10bar时，该系统可以进行模拟。但它不能模拟出口压力为500bar的情况。当出口边界条件为500bar时，活塞腔内压力不高于500bar。所以在活塞腔里，我得到负的质量流量和压力。因此，模拟不会继续。当我观察腔内的压力时，它简单地假设为中等压力，这是在活塞端口定义的压力。活塞的压缩运动不会影响活塞内部的压力，因为活塞内的压力是由活塞端口的压力给出的。你知道怎么增加活塞内部的压力吗?这样我的活塞内部的压力就可以超过500bar了。

我添加了代码和框图。任何帮助都将不胜感激！非常感谢!

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//----------------------------------------------------------------------------
// Name of Model: Hochdruckreiniger3
// Date: 11/15/20 21:16:37
// Generated from Modelica Diagram Editor
//----------------------------------------------------------------------------
model Hochdruckreiniger3
    //Declaration(s)
    Real V_max = 0.000003;
    Real V_tod = 0.000002;
    Real N = 2800;
    Real opening_NP;
    Real opening_HP;
    replaceable package medium = Modelica.Media.Water.StandardWater( );
    //Component(s)
    Modelica.Fluid.Machines.SweptVolume Swept1 (
        pistonCrossArea = 0.003131,
        clearance = 0.000250621,
        redeclare package Medium = medium,
        nPorts = 3,
        use_portsData = false,
        p_start = system.p_start,
        use_T_start = true,
        T_start = 293.15);
    inner Modelica.Fluid.System system;
    Modelica.Mechanics.Translational.Sources.Position Posit1 (exact = true, useSupport = false);
    Modelica.Blocks.Sources.Sine Sine1 (
        amplitude = 0.005567,
        freqHz = 46.66,
        offset = 0.005567,
        phase = -Modelica.Constants.pi/2);
    Modelica.Fluid.Sources.FixedBoundary boundary (p = 500e5, redeclare package Medium = medium, nPorts = 1);
    Modelica.Fluid.Pipes.DynamicPipe pipe2 (
        length = 0.5,
        diameter = 0.03,
        redeclare package Medium = medium,
        momentumDynamics = system.momentumDynamics,
        massDynamics = Modelica.Fluid.Types.Dynamics.DynamicFreeInitial,
        energyDynamics = system.energyDynamics,
        allowFlowReversal = system.allowFlowReversal,
        modelStructure = Modelica.Fluid.Types.ModelStructure.av_b);
    Modelica.Fluid.Pipes.DynamicPipe pipe3 (
        length = 0.5,
        diameter = 0.03,
        redeclare package Medium = medium,
        momentumDynamics = system.momentumDynamics,
        massDynamics = Modelica.Fluid.Types.Dynamics.DynamicFreeInitial,
        energyDynamics = system.energyDynamics,
        allowFlowReversal = system.allowFlowReversal,
        modelStructure = Modelica.Fluid.Types.ModelStructure.a_vb);
    Modelica.Fluid.Pipes.DynamicPipe pipe4 (
        length = 0.5,
        diameter = 0.03,
        redeclare package Medium = medium,
        momentumDynamics = system.momentumDynamics,
        massDynamics = Modelica.Fluid.Types.Dynamics.DynamicFreeInitial,
        energyDynamics = system.energyDynamics,
        allowFlowReversal = system.allowFlowReversal,
        modelStructure = Modelica.Fluid.Types.ModelStructure.a_vb);
    Modelica.Fluid.Sources.FixedBoundary boundary1 (p = 500e5, redeclare package Medium = medium, nPorts = 1);
    Modelica.Fluid.Pipes.DynamicPipe pipe5 (
        length = 0.5,
        diameter = 0.3,
        redeclare package Medium = medium,
        momentumDynamics = system.momentumDynamics,
        massDynamics = Modelica.Fluid.Types.Dynamics.DynamicFreeInitial,
        energyDynamics = system.energyDynamics,
        allowFlowReversal = system.allowFlowReversal,
        modelStructure = Modelica.Fluid.Types.ModelStructure.av_b);
    Modelica.Blocks.Sources.Pulse Puls1 (period = 0.02142, width = 45.331);
    Modelica.Blocks.Sources.Pulse Puls2 (period = 0.02142, startTime = 0.01071, width = 45.331);
    Modelica.Fluid.Valves.ValveLinear NDVentile (dp_nominal = 94.35, m_flow_nominal = 0.05867441, redeclare package Medium = medium);
    Modelica.Fluid.Valves.ValveLinear HDVentile (dp_nominal = 95, m_flow_nominal = 0.05867441, redeclare package Medium = medium);
    Modelica.Fluid.Sensors.Pressure pressureamSweptvolume (redeclare package Medium = medium);
    Modelica.Fluid.Sensors.Pressure PressureanderPipe (redeclare package Medium = medium);
    Modelica.Fluid.Sensors.Pressure PressureanBeginnderHochdruckventile (redeclare package Medium = medium);
    Modelica.Fluid.Sensors.Pressure Pressure_amEndederHDVentile (redeclare package Medium = medium);
    Modelica.Fluid.Pipes.DynamicPipe pipe1 (
        length = 0.5,
        diameter = 0.03,
        redeclare package Medium = medium,
        momentumDynamics = system.momentumDynamics,
        massDynamics = Modelica.Fluid.Types.Dynamics.DynamicFreeInitial,
        energyDynamics = system.energyDynamics,
        allowFlowReversal = system.allowFlowReversal,
        modelStructure = Modelica.Fluid.Types.ModelStructure.a_vb);
    Modelica.Fluid.Vessels.ClosedVolume volume (
        V = 7e-9,
        nPorts = 2,
        use_portsData = false,
        redeclare package Medium = medium,
        p_start = 26.5e5);


equation
    if der(Sine1.y)>=0 then
            opening_NP=1;
            opening_HP=0;
           else
            opening_NP=0;
            opening_HP=1;
          end if;
    //Connection(s)
    connect(Posit1.flange, Swept1.flange);
    connect(Sine1.y, Posit1.s_ref);
    connect(pipe2.port_b, Swept1.ports[1]);
    connect(Swept1.ports[2], pipe3.port_a);
    connect(pipe4.port_b, boundary1.ports[1]);
    connect(boundary.ports[1], pipe5.port_a);
    connect(pipe5.port_b, NDVentile.port_a);
    connect(NDVentile.port_b, pipe2.port_a);
    connect(NDVentile.opening, Puls1.y);
    connect(Puls2.y, HDVentile.opening);
    connect(pipe3.port_b, HDVentile.port_a);
    connect(pressureamSweptvolume.port, Swept1.ports[3]);
    connect(PressureanderPipe.port, pipe3.port_a);
    connect(PressureanBeginnderHochdruckventile.port, HDVentile.port_b);
    connect(Pressure_amEndederHDVentile.port, HDVentile.port_a);
    connect(pipe1.port_a, PressureanBeginnderHochdruckventile.port);
    connect(pipe1.port_b, volume.ports[1]);
    connect(volume.ports[2], pipe4.port_a);
end  Hochdruckreiniger3;

Answer 1

您可以通过单击栏上的向下箭头来查看注释，线号在左侧，除非您已经使用图形编辑器对模型进行了建模。