Purpose:
* To demonstrate the characteristics of flow over weirs.
* To determine the 'Coefficient of Discharge' for each type of weir.

Introduction:
In open channel hydraulics, weirs are commonly used to either regulate or to measure the volumetric flow rate. They are of particular use in large scale situations such as irrigation schemes, canals and rivers. For small scale applications, weirs are often referred to as notches and invariably are sharp edged and manufactured from thin plate material.

Apparatus:
Hydraulics Bench incorporates a weir channel. The rectangular notch weir or (V) vee notch weir to be tested is clamped to the weir carrier in the channel by thumb nuts. 4

2

5

8

7

6

3
1

Figure 1: Flow over Weirs - Figure 2: Flow over Weirs -
vee notch weir rectangular notch weir
1
5

2
6
Hydraulics BenchBasket of glass spheres
3
Weir channelVolumetric measuring tank
4
(V) Vee notch weir7
Rectangular weir
Hook & point gauge Hook Gauge and Scale8

There are different shapes of weirs that can be used to measure the volumetric flow rate. These shapes with their dimension are shown in fig 3 below.

Figure 3: Details of weirs

Theory:
* Rectangular Weir:
A rectangular notch is a thin square edged weir plate installed in a weir channel as shown in figure 4.

| |
Figure 4: Rectangular Notch
Consider the flow in an element of height δh at a depth h below the surface. Assuming that the flow is everywhere normal to the plane of the weir and that the free surface remains horizontal up to the plane of the weir, then velocity through element 2gh

∴ Theoretical discharge through element dQ=v.dA= 2gh.b.dh Integrating between h = 0 and h = H
Total theoretical discharge Qth=0H2gh.B.dh=B2g0Hh12.dh
So, Qth=23B2gH32
In practice the flow through the notch will not be parallel and therefore will not be normal to the plane of the weir. The free...

...force generated by impact of the jet on vanes of various shapes like flat plate, conical cup and hemispherical cup. Besides that, the results from the experiment have to be compared with the theoretical calculations too.
1.0 Introduction
Water turbines are widely used throughout the world to generate power. By allowing fluid under pressure to strike the vanes of a turbine wheel, mechanical work can be produced. Rotational motion is then produced by the...

...kkkkkkkkk
CVEN-3313 Theoretical Fluid Mechanics
MODULE#4 : Application of Impact on a Jet
1. OBJECTIVE
To use the momentum equation to estimate the force exerted by a jet on a stationary target.
2. THEORY
The momentum equation in the vertical (z) direction can be written as:
Applying the momentum equation for a control volume including the forces acting on a flat target or hemispherical target gives:
(1a : flat)...

...Impact of A Jet
Philip Mah Koon Yue
Mohananda a/l Anantha Krishnan
Ahmad Saeed Abood
Eleanor Hang Lee Shean
Chan Jun Hoe
School of Engineering
Taylor’s University
Malaysia
23 March 2011
Table of Content
Abstract
3
1. Introduction
3
2. Experiment Design
3
2.1 Materials
3
2.2 Methods & Procedures
4
3. Results and discussion
5
4. Conclusion and Recommendations
8
References
8
Appendix
9
Abstract
The...

...1.0 ABSTRACT
The purpose of the impact of jet experiment is to design a system to determine the force generated by the impact of jet on a variety of target vanes. A formula is given to calculate the reaction force at the different vanes caused by the jet. At the end of the experiment, the data collected and results calculated will then be compared to theoretical values which are given. Students are expected to be able to...

...
IMPACT OF a jet
ABSTRACT
The objective of this experiment is to determine the force exerted by a jet of water on vanes of various shape.Three different shape of vanes;flat plate,conical cup,and hemispherical cup are used for this experiment.The results obtain from the experiment are then used to compare with the theoretical results.Force generated on the surface of vane depends on the rate of change of momentum and it can be calculated...

...IMPACT OF A JET
OBJECTIVES:
To measure the force generated by impact of the jet on vanes of various shapes.
To compare the results from the experiment with the theoretical calculations.
APPARATUS:
The JetImpact Apparatus
Volumetric Hydraulic Bench/Water
3 different shapes of vanes; Flat Plate, Conical Cup, and Hemispherical Cup
Stop Watch
1. INTRODUCTION
One way of producing mechanical work from...

...11.
IMPACT OF A JET
Introduction
Water turbines are widely used throughout the world to generate power. In the type of
water turbine referred to as a Pelton† wheel, one or more water jets are directed
tangentially on to vanes or buckets that are fastened to the rim of the turbine disc. The
impact of the water on the vanes generates a torque on the wheel, causing it to rotate
and to develop power. Although the concept is...

...Impact Of a Jet
Introduction:
Over the years, engineers have found many ways to utilize the force that can be imparted by a jet of fluid on a surface diverting the flow. For example, the pelt on wheel has been used to make flour. Further more, the impulse turbine is still used in the first and sometimes in the second stages of steam turbine. Firemen make use of the kinetic energy stored in a jet to deliver water above...

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