# Homework Help: Pressure Drop

1. Jul 11, 2015

### Merttt

1. The problem statement, all variables and given/known data
During measurement of pressure differences by the using orifice and an electronic transducer, we can have some oscillation on diaphragm, I try to define this effect by the calculating pressure drop from vena contracta to transducer. I say that oscillation is 30 percent (maybe its too much, if someone has idea about it, could be nice). And I estimate frequency as 300 Hz.

thickness of transducer 0.203 mm
maximum volume deflection : 13.64 cubic milimeter
maximum deflection in center:0.1798 mm
surface area : 227.57
after oscillation,
volume deflection : 4.1 cubic milimeter (V1-V2)
maximum deflection in center: 0.1798 mm
Surface area : 227.54 mm2

My problem is how I can define the velocity then?

V(t) = (V1-V2) sin(wt) w= 2 pi f t I think according to formula t means time; f frequency;
how i can define the time when frequency is 300 Hz?

On the other hand does frequency different when Diapghram is in V1 position or V2 Position.

After defining V here I can define volume flow rate Q =dV/dt m3/sn
Q= A.c

Here c shows velocity and I can calculate pressure loses then.

2. Relevant equations

3. The attempt at a solution

2. Jul 16, 2015