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我想模拟板式换热器模型，并使用 Modelica-Fluid-Library 中的默认版本。为了指定默认版本，我根据 VDI Wärmeatlas 2006，Mm1 构建了所有必要的传热参数和方程（Nusselt 等）和压力损失。我已经尝试了很长时间来查找并纠正所有错误，但最终我来到了一个“死点”。

最后的错误消息是：

Check of Fluid_Test1_PHE_Temp7.Examples.HeatExchanger.HeatExchangerSimulation:
Error: The model is not well-posed.
The model has
  484
scalar unknowns and
  480
scalar equations.
Using the given settings of the parameters, the difference could be reduced to
  4
Error: The following parameters don't have any value:
  HEX.pipe_1.diameter
  HEX.pipe_2.diameter

Warning: The following inputs lack binding equations:
  HEX.pipe_1.heatTransfer.roughnesses
  HEX.pipe_2.heatTransfer.roughnesses

Error: The problem is structurally singular:
It has 488 scalar unknowns and 484 scalar equations.
  The Real part has 456 unknowns and 452 equations.
  The Integer part has 32 unknowns and 32 equations.
  The Boolean part has 0 unknowns and 0 equations.
  The String part has 0 unknowns and 0 equations.
Attempting to further localize singularity.

The model has the same number of unknowns and equations.
Attempting to further localize singularity.

The model has the same number of unknowns and equations.
Attempting to further localize singularity.

The model has the same number of unknowns and equations.
The model has the same number of unknowns and equations.
Note: The input connector p of HEX.pipe_1.mediums[1] is not connected from the outside.
 It is likely that it should have been connected, and recursive check will assume this.
 The missing connection is a likely cause of errors in the model.
Note: The input connector h of HEX.pipe_1.mediums[1] is not connected from the outside.
 It is likely that it should have been connected, and recursive check will assume this.
 The missing connection is a likely cause of errors in the model.
The model has the same number of unknowns and equations.
Note: The input connector p of HEX.pipe_1.mediums[2] is not connected from the outside.
 It is likely that it should have been connected, and recursive check will assume this.
 The missing connection is a likely cause of errors in the model.
Note: The input connector h of HEX.pipe_1.mediums[2] is not connected from the outside.
 It is likely that it should have been connected, and recursive check will assume this.
 The missing connection is a likely cause of errors in the model.
The model has the same number of unknowns and equations.
The model Fluid_Test1_PHE_Temp7.Examples.HeatExchanger.HeatExchangerSimulation component HEX.pipe_1 is structurally singular.
when assuming the most generic outside couplings to all the flow variables of its connectors
and that non-physical connectors will impose suitable constraints.
The reported problems with connections are the likely cause of the singularity.
Singularity of Fluid_Test1_PHE_Temp7.Examples.HeatExchanger.HeatExchangerSimulation is in the component HEX.pipe_1, class Fluid_Test1_PHE_Temp7.Pipes.DynamicPipe.
ERROR: 3 errors were found
WARNING: 1 warning was issued

有人可以帮助我吗？我也可以通过邮件将模型发送给某人让其检查。

问候乔治

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1 回答 1

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我无权访问您的模型，但错误消息表明问题出在与 HEX.pipe_1.mediums （这是一个数组）的连接上。看起来他们没有（正确地？）连接。

你有理由认为这不是问题吗？

此外，在进行任何更多测试之前，我还强烈建议您为 HEX.pipe_1 和 HEX.pipe_2 提供（非零）直径，并为传热模型的粗糙度分量提供“绑定方程”。这些问题可能会“掩盖”其他担忧。

让我知道这是否有帮助。

于 2011-12-29T16:58:50.730 回答