Flow Rate and Pressure in Parallel Pipe System


Thread Starter


I need some help in understanding as to how do i go about fixing a glitch in my project where I am stuck.

Background - I am designing a Water Flow Meter using an Arduino and a water flow sensor who limits are - (60Litres/Min and Pressure <1.7Mpa). The entire project is ready but while testing at the facility I have encountered a problem.

Problem - The water pump which feeds the water into the pipe (between which my system will be put in) at 300 Litres per Minute. The diameter of the pipe is 1.5Inches.

Advice needed - I was thinking, and please correct me or point me in the right direction. If i create a small thin branch of pipe parallel to the main 300 litres/min pipe and attach my system, maybe the flow rate will decrease to be less than 60 litres per min. Then I can extrapolate the total flow basis the reading i get in that thin pipe.

Is my understanding correct or totally flawed?

If it is correct, can you point me or tell me the setup I should put? Like what should be the diameter of my thin pipe, so as to make sure the flow rate and pressure of the arduino sensor are not overloaded?

Thank you very much.

If the meter does not meet the design requirements, do not use it.

If you want a working measurement, then you have to do it right, and it will be less costly than an improvised fix.
What are the flow rate requirements from the pump trough the pipe to the destination? Is the pump positive displacement or radial (roto-dynamic)? If the pump is radial you can throttle the flow to the required flow rate keeping minimum flow, cavitation, and best efficiency point (BEP) in mind. This would require a hydraulic analysis. This could require changing the impeller diameter or piping diameter. If the required flow rate is 60 L/M or below you should be able to use the flow meter you have.

You may be able to measure the flow in a small line while having another line shunting it. If your sensor is a differential pressure transmitter it may be simply a matter of having an orifice in parallel.