Singular phenomenon in example BatchPlant_StandardWater

[KLG-Dongbeiness]

There is still room for optimization of the corresponding equations of some components in the example case BatchPlant_StandardWater in Modelica.Fluid version3.2.3.
For example, in valve V1, the Jacobian of corresponding scalar nonlinear equation of variable dp is singular. Such singular case handled by different tools may lead to different results. So it is hoped that the modeling can be improved to eliminate this phenomenon.