# Pipe Flow Experiment

Topics: Fluid dynamics, Plumbing, Liquid Pages: 8 (533 words) Published: October 16, 2014
﻿Pipe Flow Experiment

Purpose
The purpose of the experiment is providing an opportunity to students of experience to familiarize with some key aspects of fluid flow in pipe, notably friction losses and verify theory. In this experiment, required equipment are a water tank, piezometric tubes, pump, a stop watch, empty bucket and a digital weight scale. By operating the pump to keep the water is full in the water tank, and measuring the height of water in the piezometric tubes in different height of water outlets. And measuring the flow rate of water in different height outlets with the stopwatch, empty bucket and digital weight scale. After experiments done, use the data of experiments to calculate the velocity and the flow rate of water in the pipe through by the Bernoulli equation. Then compare the calculate results and practical results to approve the theory. The calculated results should very be close to the practical results. There is a necessary discussion of errors due to relevant issues.

Equipment
Water pump
Water tank
Excess water collector
One transparent plastic tube for connecting the water pipe and piezometric tubes. Five plastic as piezometric tubes.
The tube for connect water tank and other tubes should has larger diameter, and the piezometric tubes have same diameter and smaller diameter. Bucket
Digital weight scale

Experiment sketch
The equipment are set up as following sketch

Water tank

The piezometric tubes

Water outlet

Procedures
1. Fill up the tank
2. Adjust the Exit height Ze to be 1300mm
2.1 Use bucket, scale, and timer to get Qm-measuring the volume of water flow to bucket in 20s. 2.2 Meanwhile, measure the height of water in piezometric tubes y1, y2, y3, y4, y5. 2.3 Assume a friction factor f

2.4 Use f to calculate Ve
2.5 Use Ve to calculate Re
2.6 Use Re, from the Moody diagram to obtain fnew
2.7 Compare f and fnew
If f≈fnew, go to step 2.8
f f≠fnew, back to step 2.3 and repeat
2.8 Use f to calculate the correct Ve
2.9 Use Ve obtained in step 2.6 by using equation Q=A*Ve to get Qcal 3. Compare Qcal and Qm
4. Compare Head loss obtained by two methods
4.1 Method 1- direct measurement
Choose two readings among y1, y2, y3, y4, y5

4.2 Subtract them to get friction loss
Method 2-Dancy Weisbach equation
Friction loss =f*(l/d)*Ve2/2g
5. Go back to step 2. Change Ze to 1600 repeat step 2 to 4.2 6. After completion of Ze=2500. The lab is finished

Results

Pipe diameter d=0.019m
Pipe length l==13.3 me
Local loss coefficients K=0.5
Water density ρ=1000kg/m3
Velocity is equal 1*10-3pa*s
Za=3245mm

Calculation

H=Za-Ze
Assume f=0.020
Ve= {2*g*H / [1+k+f*(l/d)]}1/2
Re=ρ*Ve*d/u

Use the fnew calculate Ve.
Calculate Qcal by the equation Q=A*Ve where A= (3.14*0.019^2)4

Calculate dh
dh measure is subtraction of y3,y4
We can use any two of y1, y2, y3, y4, y5.
Friction loss =f*(l/d)*Ve2/2g where l is 2020 mm

Calculation Summary