hydraulic pressure sensor and hydraulic flow rate sensors dont' work when used together

When i use the hydraulic pressure sensor and hydraulic flow rate sensors together, then the pressure sensor does not show any thing (zero), but when any one is used then it works fine. why is it so

Answer 1

[Yifeng Tang]

I suspect that you connected the sensors in series ...

A pressure sensor is a sensor for an "across variable", so it's always measuring a pressure DIFFERENCE. When the B port is connected to a hydraulic reference, which is at 0 Pa, the measured value is then the absolute pressure.

A flow rate sensor on the other hand is for a "through variable". It should be placed in line with the flow being measured.

An analogy to Voltmeter vs Ampere meter may help. Pressure is like voltage and flowrate is like current. The sensors should be placed accordingly.

More on across vs through variables:

https://www.mathworks.com/help/physmod/simscape/ug/basic-principles-of-modeling-physical-networks.html#bq89sba-3