Interaction of Mechanical and Hydraulic Systems




I am trying to model the above system in AMESIM, and analyse the step response of the system. The next picture is my model:


sdaasf.PNGEven though I made sure that the outlet pressure of the tank is zero such that the flow at port 2 of TK10 is positive, I always get the error which says that the Simulation has stopped because the flow at port 2 of TK10 is negative. What should I do to change that or anything else in the model which might help me? Thanks in advance. 


Re: Interaction of Mechanical and Hydraulic Systems


The flow on the rod side of your piston is blocked because of the hydraulic plug.
So the flow (rod side) induced by the motion of your piston cannot occure
Use a tank instead of the hydraulic plug

Re: Interaction of Mechanical and Hydraulic Systems

Siemens Phenom Siemens Phenom
Siemens Phenom

Hi @Foxtrot


You have to take @mAx's remark into account.


There are a few more things to change:

- the step force applied on the mass, you don't need to use the 'port splitters' as I call them, just stick a mechanical node between the mass and the spring-damper

- the model should actually fill the tank from the bottom

- the exit of the tank has to take into account the small pipe (d, L)


The model could look like this:


You will notice the orifices at the ports of the hydraulic cylinder, you should use large enough diameters so they don't restrain the flow too much.

This model should get rid of the negative flow rate message you are getting.