Fluid Lab

Table of Contents:-

Introduction 4

Theory 4

Nomenclature 4

Experimental Conditions 5

Equations 5

Sample Calculation 6

Apparatus 7

Procedure 7

Results

Tabulated Results 8

Graphs 9

Statement of Uncertainty

Qualitative 10

Quantitative 10

Conclusion 11

Bibliography 11

Introduction:

Aerodynamics is one of the major studies in the world of fluids. Airglow around a body has a lot of effects on the body itself. This airflow around the body depends on several factors like shape, size and surface structure. In this experiment we will study about the effects of shape of the body and its surface structure on the airflow around it. To study the airflow based on shape and surface structure we will be suing a football and a soccer ball. We calculate the drag coefficients of both the balls when placed in the wind tunnel at a constant air flow.

Theory:

Drag can be defined as the air resistance a body faces when in motion. Drag acts in the direction opposite to the motion of the body hence causing a reduction in speed as well as unsteady motion of the body. Drag depends on a lot of factors including size, shape etc.

Drag force can be expressed as,

F_D=0.5*ρ*u^2*C_D*A

Drag coefficient also depends on Reynolds number.

Re=(u*D)/V

The main finding of this experiment is the drag coefficient,

C_D= (2*F_D)/(ρ*u*A)

2.1 Nomenclature

S No Symbol Quantity

𝜌 Density

U Stream Velocity

A Cross Section

Cd Drag coefficient

𝜌 Density

d Diameter

V Kinematic Viscosity

D Drag Force

Experimental Assumptions:

The test section has no leaks.

The ambient conditions do not change.

Flow is steady

Mounts do not affect the nature of flow.

Equations:

F_D=0.5*ρ*u^2*C_D*A

C_D= (2*F_D)/(ρ*u*A)

Where A= b * h

Apparatus:

3.1 Wind Tunnel

Wind tunnel is an artificial environment created to study the wind flow around a body. Air is taken in from the behind using a fan. The testing is done at the test section is located