Question

你好

我的模型有一个dp = 1 bar的泵和一个减少1 bar dp的管道。泵必须在两个方向上工作。此外，还有一个三通阀，可为侧面提供3 bar的低压。但是我的模型存在问题：如果我想使用标准库中的泵，它就不起作用......如果可能的话，标准库块是否有任何想法如何解决这个问题？（我希望有标准库块，因为泵特性等参数......）

以下是图片：Model

谢谢！

  model Modell_online
      Pump_mflow pump_mflow3(redeclare package Medium =
            Modelica.Media.Water.ConstantPropertyLiquidWater, show_T=true)
        annotation (Placement(transformation(
            extent={{-10,-10},{10,10}},
            rotation=270,
            origin={-50,10})));
      Modelica.Fluid.Pipes.StaticPipe pipe(
        redeclare package Medium =
            Modelica.Media.Water.ConstantPropertyLiquidWater,
        length=0.5,
        diameter=0.1,
        redeclare model FlowModel = 
            Modelica.Fluid.Pipes.BaseClasses.FlowModels.NominalLaminarFlow (
              dp_nominal=100000, m_flow_nominal=3),
        p_a_start=400000,
        p_b_start=300000) annotation (Placement(transformation(
            extent={{-10,-10},{10,10}},
            rotation=90,
            origin={-10,10})));
      Modelica.Blocks.Sources.Pulse pulse(
        amplitude=2,
        offset=-1,
        period(displayUnit="min") = 600)
        annotation (Placement(transformation(extent={{-100,60},{-80,80}})));
      inner Modelica.Fluid.System system
        annotation (Placement(transformation(extent={{-140,80},{-120,100}})));
      Modelica.Fluid.Sources.Boundary_pT p_source(
        redeclare package Medium =
            Modelica.Media.Water.ConstantPropertyLiquidWater,
        nPorts=1,
        p=300000) annotation (Placement(transformation(
            extent={{10,-10},{-10,10}},
            rotation=0,
            origin={70,10})));
      Modelica.Blocks.Continuous.FirstOrder firstOrder(T(displayUnit="s") = 10)
        annotation (Placement(transformation(extent={{-60,60},{-40,80}})));
      VarEx VarEx_1(redeclare package Medium = 
            Modelica.Media.Water.ConstantPropertyLiquidWater) annotation (Placement(
            transformation(
            extent={{10,-10},{-10,10}},
            rotation=270,
            origin={30,10})));
    equation 
      connect(pump_mflow3.port_b, pipe.port_a) annotation (Line(points={{-50,0},{-50,
              -20},{-10,-20},{-10,0}},   color={0,127,255}));
      connect(pipe.port_b,pump_mflow3. port_a) annotation (Line(points={{-10,20},{-10,
              40},{-50,40},{-50,20}},    color={0,127,255}));
      connect(pulse.y, firstOrder.u)
        annotation (Line(points={{-79,70},{-62,70}}, color={0,0,127}));
      connect(p_source.ports[1], VarEx_1.port_ExpansionVessel)
        annotation (Line(points={{60,10},{40,10}}, color={0,127,255}));
      connect(VarEx_1.port_warm, pump_mflow3.port_a) annotation (Line(points={{30,20},
              {30,40},{-50,40},{-50,20}}, color={0,127,255}));
      connect(VarEx_1.port_cold, pipe.port_a) annotation (Line(points={{30,0},{30,-20},
              {-10,-20},{-10,0}}, color={0,127,255}));
      connect(firstOrder.y, pump_mflow3.m_flow_set) annotation (Line(points={{-39,70},
              {-30,70},{-30,10},{-38,10}}, color={0,0,127}));
      annotation (Icon(coordinateSystem(preserveAspectRatio=false, extent={{-140,
                -100},{140,100}})), Diagram(coordinateSystem(preserveAspectRatio=
                false, extent[enter image description here][1]={{-140,-100},{140,100}})),
        experiment(StopTime=1200));
    end Modell_online;

Answer 1

在Backflow Orifice (Zeta)中提出了类似的问题。

您需要一个散热器来消除泵在闭合回路中产生的热量。
MSL泵的流量反转能力有限。

我在这里用https://drive.google.com/file/d/1LEn2_ifoFTrdX33JEe2awQmvePBERVVz/view?usp=sharing

在示例3中，请注意它不是真正的闭合电路，因为压力接收器也可用作散热器。

论文On the formulation of steady-state initialization problems in object-oriented models of thermo-hydraulic systems可能对您有用。

致以最诚挚的问候，

Rene Just Nielsen

Modelica标准泵（两个方向）

你好

谢谢！

1 个答案: