Compressor - Regulator - Plenum - Exit. Regulator problem

[jlchard1]

Hi,

I have a workbench test set up which consists of a compressor, followed by a 6bar supply line, followed by a regulator (for bringing the pressure down to 2bar) followed by a plenum chamber that leads to a slot that vents to atmospheric. The slot is approximately the same area as the supply line pipe. There is a pressure tapping in the plenum chamber to measure stagnation conditions. I want a plenum stagnation pressure of 2bar. The flow rate at this pressure is 0.1294kg/s which converts to 3240 l/min given the density of the air at this point. The regulator I have has flow characteristic curves for an input pressure of 7bar but shows an output of 2bar is easily achievable at this flow rate. I understand the input pressure is 6bar in my case however, given the high max flow rate shown by the characteristic curve I believe I should still be able to achieve 2bar output with a 6bar input. The problem: The maximum plenum pressure I am able to achieve is about 1.3bar. If I try and increase the pressure past this nothing happens, it is as if the flow is choked. Given that the regulator should be able to produce 2bar output with a 6bar input at the design flow rate, why would my regulator be unable to produce 2bar plenum conditions? Any help is much appreciated. Any more details required please ask.

Thankyou

James

 

[Achy47]

Hi James,

Thank you for sharing your setup and the issue you are facing. Based on the information provided, it seems like your regulator is not able to achieve the desired 2bar output pressure in the plenum chamber. There could be several reasons for this, and I will try to address them below.

Firstly, it is important to ensure that your regulator is compatible with the flow rate and pressure requirements of your setup. It is possible that the regulator you are using is not designed to handle such high flow rates and therefore cannot achieve the desired output pressure. I would suggest checking the technical specifications of the regulator to see if it is suitable for your setup.

Secondly, it is possible that there is a problem with the regulator itself. It could be malfunctioning or there could be a blockage or restriction in the internal mechanism. I would suggest checking the regulator for any signs of damage or clogging and if necessary, have it inspected or replaced.

Another possible reason for not being able to achieve the desired 2bar output pressure could be due to the setup of your compressor and supply line. It is important to ensure that the compressor is able to provide a consistent and sufficient air supply to the regulator. If the compressor is not able to keep up with the demand, it could result in lower output pressure.

Lastly, I would suggest checking the calibration of your pressure tapping in the plenum chamber. It is possible that the pressure measurement is not accurate, which could be giving you false readings.

I hope this helps in resolving your issue. If you need any further assistance, please do not hesitate to ask. Good luck!