Abstract

This experiment is conducted by using Basic Weir Apparatus, F1-13 in order to

investigate its functioned and characteristic by using two simple weirs, rectangular and

triangular notch. Then, the values of coefficient discharged are measured. This experiment

showed how the fluid can flow over into open-channel with different type of weirs. Thus, the

fluid flow and the discharge coefficient and volumetric flow rate is determined.

The coefficient of discharge can be determined from the height of the free surface of

water above the notch and the corresponding volume flow rate. The equipment and

apparatus must be set up carefully to gain appropriate and accurate results. The value and

reading taken involve is volume and time. Then, this reading is used to calculating flow rate.

All this observation values will be applied in the coefficient of discharge equation to

determine whether the observation is true or not by comparing it with theoretical values.

Introduction

The particular laws that described the quantitatively behaviour of fluid involved the

conservation of mass, energy and momentum in each application. The fluids can be treated

as continuous media base on the application of the classical laws of static’s, dynamics and

thermodynamics.

A special equipment is used which is the Hydraulic Bench Description service

module, F1-10. It provides the necessary facilities to support a comprehensive range for the

hydraulic models which it is designed to demonstrate a particular aspect of hydraulic theory.

The specific hydraulic model for this experiment was the Basic Weir Apparatus, F1-13. This

model consists of two simple weirs, a rectangular notch and a vee notch.

In this experiment, two simple weirs is used. First is rectangular notch and second is

vee notch. Vee notch is one of the most precise discharge measuring devices, suitable for a

wide range of open channel flows.

Notch is a device used to measure rate of flow of a liquid through a small channel or

a tank. It is also defined as an opening in the side of a tank or a small channel in such a way

that the liquid surface in the tank or channel is below the top edge of the opening.

Weir is a concrete structure placed in an open channel over which the flow occurs. It

is generally in the form of vertically wall with a sharp edge at the top, running all the way

across the open channel. Weir is a bigger size than notch.

Figure 1: The sample image of simple weirs, rectangular notch and a vee notch.

Objectives

To determine the characteristics of open- channel flow over, firstly a rectangular

notch and then vee notch.

To determine the value of discharge coefficient for both notches.