Velocity of a water jet given water pressure and diameter?

Click For Summary

Homework Help Overview

The discussion revolves around determining the velocity of a water jet exiting a garden hose, given specific parameters such as the hose diameter and water pressure. The subject area includes fluid dynamics and the application of pressure principles.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to relate pressure to velocity but expresses uncertainty about the appropriate equations to use. They consider the role of flow rate and time in their calculations. Some participants suggest using orifice flow equations and reference external resources, while others mention applying Newton's second law.

Discussion Status

The discussion is active, with various approaches being explored. Participants are providing guidance on potential equations and concepts, but there is no explicit consensus on a single method or solution yet.

Contextual Notes

The original poster notes a specific scenario involving a garden hose with a diameter of 1/2" and a pressure of 40 psi, indicating a focus on practical applications of fluid dynamics. There is also mention of estimating flow rates, which may introduce additional complexity to the problem.

rufnrede
Messages
1
Reaction score
0
I need to determine the velocity of a water jet. For example, if a garden hose is 1/2" in diameter and we assume that the water pressure is 40psi, what would be the water velocity (in ft/s) as it exits the hose (assuming no nozzle)?



We know Pressure = force/area, but I want to know the velocity in feet/second, so I don't know what equation to use!



Since velocity has a time component, would we need to introduce another factor? Maybe estimate the gallons per minute? Is this known for a typical garden hose? Thank you in advance!
 
Physics news on Phys.org
You can estimate flow speed from an orifice given just it's size, the presure and a factor that describes the shape.
Have you tried looking up orifice+flow in your textbook.
 
.32 X GPM
_________ = Ft/Sec velocity
TFA (sq. in.)
http://www.uiweb.uidaho.edu/extension/lawn/Files/Garden_Hose.htm
 
Last edited by a moderator:
Use the Newton's second law, considering a small dt amount of time.
 

Similar threads

Undergrad Find Best Water Nozzle Type & Pressure for Longest Distance
  • · Replies 32 ·
2
Replies
32
Views
12K
Question about water pressure in IPX6 water intrusion testing of an enlosure
  • · Replies 7 ·
Replies
7
Views
1K
High School Will there be water coming out of the last hole?
  • · Replies 17 ·
Replies
17
Views
2K
Force of pressurized water exiting a hose or pipe?
  • · Replies 20 ·
Replies
20
Views
11K
Undergrad Estimation and validation of water pressure at nozzle
  • · Replies 3 ·
Replies
3
Views
2K
How much air pressure is needed to push water up a column?
  • · Replies 16 ·
Replies
16
Views
6K
Pressure of water exiting a hole in PVC
  • · Replies 12 ·
Replies
12
Views
4K
How to calculate water pressure drop in cooling tower piping system?
  • · Replies 1 ·
Replies
1
Views
4K
Undergrad Calculate Pressure & Speed of Submerged Water Jet 100mm Away
  • · Replies 3 ·
Replies
3
Views
3K
Graduate How Does Jet Injection Work in Fluid Dynamics?
  • · Replies 6 ·
Replies
6
Views
2K