Shop OBEX P1 Docs P2 Docs Learn Events
does any one know — Parallax Forums

does any one know

zapmasterzapmaster Posts: 54
edited 2010-12-30 09:49 in Accessories
does anyone know a cheap way of measuring flow. In a copper line or pex line for my boiler project.
i have calculated btu's for my storage tank. I would also like to for my boiler but i need flow.
A magflow tube would be too much $. The flow rate is too low for a orifice plate and differential pressure transmitter.

Comments

  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-12-19 08:22
    You might want to ask a moderator to move this to the General Forum or to the Sensor Forum. You'll probably get more suggestions there.
    Also, you might want to add some details - what is the fluid? Is it a mixture of air and fluid or just fluid? Is it hot? What is the approximate flow rate range?
  • zapmasterzapmaster Posts: 54
    edited 2010-12-19 09:50
    more info
    the fluid is water
    the tempature is 100 to 200 deg f
    no air
    the flow rate is 0 to 5 gpm
    the cirulator is a tayco 007
    i posted here for the contest: 30% community participation: Entrants are expected to help others and contribute code on the forums or Object Exchange and use community resources. The final code should have been created by building on community code by adding unique capabilities.

    unique capabilities is what i was looking for. I just do not know how to make it aforadble for others.
  • Mike GMike G Posts: 2,702
    edited 2010-12-19 15:26
    Flow = velocity*area

    You can do a quick google search to find more information. You can also fine this stuff in 101 college physics text.
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-12-19 17:01
    zapmaster wrote: »
    ...... I just do not know how to make it aforadble for others.

    For contest purposes, is it necessary to worry about making it affordable for others? What are you yourself using now to measure flow?
  • Mike GMike G Posts: 2,702
    edited 2010-12-19 17:39
    Knowing the the gallons per minute (gpm) and area of the pipe should provide a pretty good estimate of water flow through the pipe. I'm not sure how accurate the calculation needs to be but flow = velocity*area should get zapmaster in the ballpark. I'm sure someone well versed in thermodynamics and viscosity could shed more light on the subject. This is a specialty form and as such we could get varied questions.
  • sstandfastsstandfast Posts: 39
    edited 2010-12-30 09:49
    One thing that jumps out as a simple solution would be to put an impeller in the line connected to a rotary encoder. Then, rotational velocity is directly proportional to flow rate. Or, instead of a rotary encoder, attach a magnet to the shaft of the impeller and place a Hall Effect sensor on the outside of the pipe and count the pulses. This way there is no electronics in the pipe and you don't have to worry about trying to bring leads out of the pipe (avoids leaks).

    Hope this helps.

    Shawn
Sign In or Register to comment.