Pressure in pipes related to pipe size and pump for water filtration system

[nuttall86]

Hi Guys

I am trying to use a water filter in line with a 12V water pump rather than off the mains.

The water filter requires 10psi minimum and a maximum of 125psi, I am using 15mm copper pipe and the pump is 800mm from the water filter.

I have not yet decided on a pump yet as this is why I'm trying to do the calcs. I would be very grateful for the required formulae, should I calculate including friction in pipes.

Please Help

Many Thanks

Nuttall86

 

[Bob S]

You first need to know the desired water flow rate. Then use
http://www.efunda.com/formulae/fluids/calc_pipe_friction.cfm
to get the necessary pump pressure (head).

 

[astrokreng]

Hello Nuttall86,

In order to determine the appropriate pump and pipe size for your water filtration system, there are a few factors that need to be considered. First, it is important to understand the relationship between pressure, flow rate, and pipe size. Pressure is the force exerted by the water on the walls of the pipe, while flow rate is the volume of water that can pass through the pipe in a given amount of time. The larger the pipe, the lower the pressure will be for a given flow rate. Similarly, a smaller pipe will result in higher pressure for the same flow rate.

In your case, the 15mm copper pipe will have a certain amount of friction, which will affect the pressure of the water as it travels through the pipe. This friction can be calculated using the Darcy-Weisbach equation, which takes into account the pipe material, length, diameter, and flow rate. It is important to include this friction in your calculations to ensure that the pressure at the water filter meets the minimum requirement of 10psi.

Next, you will need to determine the appropriate pump for your system. The pump will need to be able to provide enough pressure to overcome the friction in the pipes and still meet the maximum pressure requirement of 125psi at the water filter. The pump should also have a flow rate that is sufficient for your desired filtration rate.

To calculate the necessary pump pressure, you can use the Bernoulli's equation, which takes into account the elevation difference between the pump and the water filter, as well as the friction in the pipes. This will give you the minimum pressure that the pump needs to provide in order to meet the 10psi requirement at the water filter.

In summary, to properly size your pump and pipe for your water filtration system, you will need to consider the pipe size, friction, elevation difference, and desired flow rate. It may also be helpful to consult a professional or reference materials for the specific equations and calculations needed for your system. Good luck with your project!