Affect on water flow through reduced diameter garden pipe?
Been too long since I studied fluid mechanics at Uni, and I must say that when I was there I never thought I would need to know this stuff.
I have a very large commercial garden and want to get new water hoses. I obviously want to deliver as much water in as little time as possible. I was planning to have 25m lengths of hose with perhaps up to 3 or 4 in sequence (75 – 100m max). The water pressure is up to 5 bar, but will probably be used at less than max.
Hoses are available here in 3/4″ or 1/2″ diameter, however the various attachments (spray nozzle, etc.) are only available for the 1/2″ hose. An adapter to enable 1/2″ hose attachments to connect to 3/4″ hose is available.
Is there any point in buying 3/4″ hose if planning to use 1/2″ attachments? How does the final reduction in “pipe” diameter affect the quantity of flow?
Thanks in advance
A taxed mind
You will definately want to go with 3/4″ pipe. the friction loss in that length of pipe in the 1/2 inch diameter will be close to 1-2 gallons per 100 feet. You will not really lose any quantity in going from 3/4 to 1/2 with nozzles. If you use 1/2 inch hose, you will not carry the volume of water you need for the nozzles. So use 3/4 inch for volume, and the 1/2 inch nozzle will carry your pressure you need at about 30-45 psi per nozzle for a non-rotor type spray nozzle. rule of thumb in irrigation. oversize pipe to carry h20 to the desired location, and then use nozzles to carry the water to definate locations.
UNI-Spray Series Spray Heads: Overview
|
|
UNI-MIST 6500 Electrical Single Nozzle Coolubricator Positive Displacement Spray $439.42 |
|
|
Rain Bird US400 UNI-Spray Less Nozzle $39.99 |
|
|
Preval Spray Gun, Power Unit and Container $6.49 This handy pocket-size tool sprays virtually any liquid: paint, lacquer, solvent, stain, oil, cleaners and more! Just fill the container with the mixture of your choice, attach the power unit and spray away. Lightweight compact size is great for touchups!Additional containers (sold separately, Rockler# 34812)allow you to keep finish samples for perfect color-matching. Completely portable system el… |
