Mini Project Report
Submitted in partial fulfillment of the requirements for the award of the degree of Bachelor of Technology in Mechanical Engineering by SHRI HARSH (Roll No.: B060278ME)
PRABHAKAR (Roll No.: B060264ME) RAVI KUMAR (Roll No.: B060225ME) ASHISH KUMAR (Roll No.: B060205PE)
Department of Mechanical Engineering
NATIONAL INSTITUTE OF TECHNOLOGY CALICUT
This is to certify that the report entitled “FABRICATION AND ANALYSIS OF REYNOLDS EXPERIMENT SETUP” is a bonafide report of the Mini Project done by SHRI HARSH (Roll No.:
B060278ME), PRABHAKAR KUMAR(Roll No.: B060264ME), RAVI KUMAR (Roll No.: B060225ME) and ASHISH KUMAR(Roll No.: B060205PE) under my supervision, in partial fulfillment of the requirements for the award of the degree of Bachelor of Technology in Mechanical Engineering from National Institute of Technology Calicut, and this work has not been submitted elsewhere for the award of a degree.
Dr. R. VIJAYAKUMAR
Professor Dept. of Mechanical Engineering
Professor & Head
Dept. of Mechanical Engineering Place : NIT Calicut Date : 20TH APRIL 2009
ABSTRACT FABRICATION AND ANALYSIS OF REYNOLD’S EXPERIMENT SETUP.
SIGNIFICANCE OF WORK
The purpose of the project is to study the effect of Reynolds number, a dimensionless quantity, on pipe flow. Reynolds number aids in classifying the flow as laminar, transition or turbulent.
OBJECTIVE OF THE WORK
1. 2. 3.
The first objective of the project is fabrication of Reynolds experiment setup. The second objective is to find the critical velocity; that is, the velocity at which laminar flow changes to turbulent. The final objective is to experimentally determine the range of Reynolds’s number for laminar flow.
The set up consist of an upper water reservoir to which water is continuously fed. The water level is kept constant by means of an overflow system, where excess water is allowed to leave at the top of the reservoir. From the bottom of the reservoir water is led to a straight pipe made of Plexiglas. The water is then led through a valve which is used to regulate the flow rate and further through a flow meter to measure the flow rate. Finally the water goes to the drain. To visualize the flow, a dye is injected in the bell mouth tube by a needle injector and its flow in the tube is monitored whether it is flowing in straight line or it is disturbed.
1.1 1.2 1.3 Introduction Experiment setup requirements Description of work completed 1-3 4-5 5-10
CHAPTER 1 INTRODUCTION Purpose of experiment
The purpose of this experiment is to illustrate the influence of Reynolds number on pipe flows. Reynolds number is a dimensionless quantity (the ratio of dynamic forces to viscous forces) that aids in classifying certain flows. For incompressible flow in a pipe, Reynolds number based on the pipe diameter, Re = V Dρ/µ, serves well. Generally, laminar flows correspond to Re < D avg D
2100, transitional flows occur in the range 2100 < Re < 4000, and turbulent flows exist for Re D
> 4000. However, disturbances in the flow from various sources may cause the flow to deviate from this pattern. This experiment will illustrate laminar, transitional, and turbulent flows in a pipe.
Background of experiment
In fluid mechanics and heat transfer, the Reynolds number Re is a dimensionless number that gives a measure of the ratio of inertial forces ( pV2 A) to viscous forces (µ VA/ L) and, consequently, it quantifies the relative importance of these two types of forces for given flow conditions. Reynolds numbers frequently arise when performing dimensional analysis of fluid dynamics and heat transfer problems, and as such can be used to determine dynamic similitude between different experimental cases. They are also used to characterize different flow regimes, such as laminar or turbulent flow: laminar flow occurs at low Reynolds...