gubau
Mechanical
- Aug 5, 2003
- 2
Hi all
We are struggeling with the interpretation of the pressure measurement values at the end of a 5.5 m pipe (1/2"
. We try to capture the pressure wave behaviour in the first 150ms. Our procedure is as follow: a) We pressurise the pipe up to 6.5Barg with air, b) The air entry valve is closed and the complete pipe is at 6.5Barg. c) At the end where the fast pressure sensor is installed, an end cap is removed instantaneously d) The pressure behaviour a the open end is captured using a PC and software.
We record a suddend drop in pressure in the first 1.5m/s up to 3.2Barg, then the pressure remains fairly constant (drops slowly) to 2.6Barg during a time period of approximately 28ms, then the pressure drop to 1.2Barg in 10ms like a type of logarithmic curve.
Our question is what the physical pressure drop behaviour is actually like. A simulation program predicts a oscillating behaviour for the pressure measured at the end of the pipe but we do not record such a behaviour.
Could any one provide more information ?
Regards
Günther
We are struggeling with the interpretation of the pressure measurement values at the end of a 5.5 m pipe (1/2"
. We try to capture the pressure wave behaviour in the first 150ms. Our procedure is as follow: a) We pressurise the pipe up to 6.5Barg with air, b) The air entry valve is closed and the complete pipe is at 6.5Barg. c) At the end where the fast pressure sensor is installed, an end cap is removed instantaneously d) The pressure behaviour a the open end is captured using a PC and software.We record a suddend drop in pressure in the first 1.5m/s up to 3.2Barg, then the pressure remains fairly constant (drops slowly) to 2.6Barg during a time period of approximately 28ms, then the pressure drop to 1.2Barg in 10ms like a type of logarithmic curve.
Our question is what the physical pressure drop behaviour is actually like. A simulation program predicts a oscillating behaviour for the pressure measured at the end of the pipe but we do not record such a behaviour.
Could any one provide more information ?
Regards
Günther
