Definition of Aerodynamics: a branch of dynamics that deals with the motion of air and other gaseous fluids and with the forces acting on bodies in motion relative to such fluids http://www.merriam-webster.com/dictionary/aerodynamics

Other: aerios, concerning the air, and dynamis, which means force.

Bernoulli's Principle:
• The relationship between the velocity and pressure exerted by a moving liquid • States that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy. • states that the faster a fluid (such as air or water) flows over a surface, the less pressure the fluid exerts on that surface.

How it affects cars
Wind tunnels for good aerodynamcs.
The goal of the vehicle
designer is to minimize this effect on a vehicle. There are a few ways to do this.
1) Minimize the total frontal area of the vehicle. Obviously a dump truck has to push more air out of the way than a motorcycle.
2) Make the air move more easily over the vehicle. A vehicle that is 'blocky' in shape (like a jeep) won't let the air flow around it as easily as, say, a corvette. Also, ever see a wide piece of plastic sticking down under a car, up front, just before the engine? That's calles an air dam and is used to deflect air away from the underside of a vehicle. All the pipes, tubes, and other things under a car cause a lot of drag. The goal is to get the car to move through the air rather than pushing it out of the way.

Engineers use wind tunnels to fine tune the body design.

...MP4005
1
NANYANG TECHNOLOGICAL UNIVERSITY
SEMESTER 2 EXAMINATION 2012-2013
MP4005 – FLUIDDYNAMICS
April/May 2013 Time Allowed: 2 ½ hours
INSTRUCTIONS
1. This paper contains FOUR (4) questions and comprises FOUR (4) pages.
2. Answer ALL FOUR questions.
3. All questions carry equal marks.
4. This is a CLOSED-BOOK examination.
5. The Compressible Gas Tables comprising of TWELVE (12) pages are enclosed.
1 (a) Derive the area-velocity relationship in compressible flow. Describe briefly the significance of this relationship in subsonic and supersonic regimes.
(6 marks)
(b) Air at M = 0.33 (static pressure 100 kPa and static temperature 300 K) flows isentropically into a converging duct. The inlet area is 0.03 m2.
(i) Determine the exit area where the local Mach number is sonic.
(2 marks)
(ii) Determine the location inside the converging duct where the local Mach number is 0.7.
(2 marks)
(iii) What are the stagnation temperature and stagnation pressure inside the converging duct?
(2 marks)
(c) A divergent duct is now connected to the exit of the convergent duct described in part 1(b) above. The exit area of the divergent duct is 0.04 m2.
(i) What is the maximum mass flow inside the converging-diverging duct if it is choked?
(5 marks)
(ii) Determine the exit static pressure and exit Mach number when a normal shock wave appears
(a) at the exit of the diverging duct, and (4 marks)
(b) in the middle of the diverging duct? (4...

...ABSTRACT
The basic concept and operation of subsonic windtunnel was demonstrated in this experiment by conducting airfoil drag analysis on a NACA 0015 airfoil. The small subsonic windtunnel along with apparatus such as, the manometer rake, the inclined manometer and the pitot - static tube were used with different baffle settings to record varying pressure readings. To achieve this objective, some assumptions were made for the lower range of subsonic flow to simplify the overall analysis. From the obtained aerodynamic measurements using a pitot-static tube mounted ahead of the airfoil at the test section, the actual velocity was determined and by relating it to the theoretical velocity, the velocity coefficient was calculated. The velocity coefficient varies for each baffle setting by a factor of decimals, thus the velocity coefficient can be used as a correction factor. Further, the coefficients of drag were calculated for the following angles of attack, 10o, 15o, and 20o and were compared with the published values.
INTRODUCTION
The windtunnel is an absolute necessity to the development of modern aircrafts, as today, no manufacturer delivers the final product, which in this case can be civilian aircrafts, military aircrafts, missiles, spacecraft, and automobiles without measuring its lift and drag properties and its stability and controllability in a wind...

...numerically. I have
applied the second-order upwind flux and two-stage Runge-Kutta time advance schemes to the
wave equation to find the time and space discretization. First, this equation is solved
numerically and compared to exact solution. In the next steps, the validation, stability and
effects of changing boundary condition on our solution will be investigated. Finally, the results
will be presented and completely discussed.
Programming Assignment 2-Wave Equation
1. Introduction
The wave equation is an important second-order linear partial differential equation for the
description of waves – as they occur in physics – such as sound waves, light waves and
water waves. It arises in fields like acoustics, electromagnetic, and fluiddynamics. Historically,
the problem of a vibrating string such as that of a musical instrument was studied by Jean le
Rond d'Alembert, Leonhard Euler, Daniel Bernoulli, and Joseph-Louis Lagrange.
Figure 1-Wave Diffusion
Wave equation has many applications. The ideal-string wave equation applies to any perfectly
elastic medium which is displaced along one dimension. For example, the air column of a
clarinet or organ pipe can be modeled using the one-dimensional wave by substituting airpressure deviation for string displacement, and longitudinal volume velocity for transverse
string velocity.
Wave equations are examples of hyperbolic partial differential equations, but there are many...

...Experiment 3: Fluid Flow Friction and Fitting Loss
Objective
To determine the pressure or head loss in different diameters pipes, joints and valves
Theory
Pipe flows belong to a broader class of flows, called internal flows, where the fluid is completely bounded by solid surfaces. In contrast, in external flows, such as flow over a flat plate or an airplane wing, only part of the flow is bounded by a solid surface. The term pipe flow is generally used to describe flow through round pipes, ducts, nozzles, sudden expansions and contractions, valves and other fittings. When a gas or a liquid flows through a pipe, there is a loss of pressure in the fluid, because energy is required to overcome the viscous or frictional forces exerted by the walls of the pipe on the moving fluid. In addition to the energy lost due to frictional forces, the flow also loses energy (or pressure) as it goes through fittings, such as valves, elbows, contractions and expansions. This loss in pressure is mainly due to the fact that flow separates locally as it moves through such fittings. The pressure loss in pipe flows is commonly referred to as head loss. When a fluid flows through pipes, energy is lost inevitably due to frictions which occur as a result of viscous drag. Fluid friction produces eddies and turbulence, and these form of kinetic energy are eventually converted into thermal energy. Losses in...

...UNIVERSITÁ DEGLI STUDI DI UDINE Dottorato in Tecnologie Chimiche ed Energetiche
FLUIDDYNAMIC MODELLING OF WIND TURBINES
sec. D
Vr 0 D Vt
Vz Vr Vt 3
Relatori: Prof.Ing. Lorenzo BATTISTI Prof.Ing. Piero PINAMONTI
Dottorando: Dott.Ing. Luca ZANNE
Udine 21 Maggio 2010
Summary
Introduction PART I : HAWT analysis HAWT Fluiddynamics A turbomachinery approach Inverse design
Summary
PART II : VAWT analysis VAWT fluiddynamics VAWT experimental analysis VAWT free vortex wake Results and conclusions
Introduction
Wind energy market (EWEA) Installed capacity
Offshore WE market (EWEA)
Aim of the thesis & thesis outline
The aim of the thesis is to analyze the fluiddynamic models of wind energy conversion systems, pointing out the limitations of current engineering models and proposing innovative solutions from the design point of view The research activities have been divided in two main parts, following the different rotor – flow interaction characteristics: 1. Horizontal axis wind turbines - HAWT; 2. Crossflow wind turbines, as vertical axis wind turbines - VAWT.
Part I : HAWT analysis HAWT fluiddynamics
HAWT fluiddynamics is mainly based on the actuator disk concept
HAWT...

...FluidDynamics
– Viscosity
Dave Foster
Department of Chemical Engineering
University of Rochester
Email: dafoster@che.rochester.edu
1
Chemical Engineering
What do Chemical Engineers Do?
Manufacturing
Research
Biotech
Chemical
Pharmaceutical
Medical
2
OK, first a little background
Fluid Mechanics is the study of fluids either in
motion (FluidDynamics) or at rest (Fluid Statics)
Fluids are either gas or liquid
Solids are NOT fluids
Properties of the fluid are things like density,
pressure, temperature, and VISCOSITY!
3
Fluid – a definition
A substance that deforms continuously under
the action of shear stress
Gas or Liquid
Solids can resist a shear stress, a fluid can’t
4
Applications of Fluid Mechanics
Explains blood flow in capillaries of a few
microns in diameter to crude oil flow
through an 800 mile long, 4 ft diameter pipe
Explains why airplanes are streamlined
with smooth surfaces
Explains why golf balls are made will
dimpled surfaces for most efficient travel
5
Drag (Pounds of Force)
Effect of Dimples on Golf Balls
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Drag for Sphere
Drag for Golf Ball
0
100
200
300
400
Velocity (Feet per Second)
6
A List of Some Applications
Coating...

...1. Identify each of the following statements as either true or false. If false, explain why.
(a) Viscosity is a measure of how easily a fluid flows.
(b) Although important, fluids are not essential to many living things.
(c) A meniscus forms when water particles adhere to the sides of their container.
(d) Buoyancy, like water pressure, acts in all directions.
2. Describe the relationship between mass, volume, and density of matter.
3. Use the particle theory to explain the differences between solids, liquids, and gases.
4. Comment on the accuracy of the statement below. Describe some exceptions to the statement if there are any. In general, solids are denser than liquids, and liquids are denser than gases.
5. Use the particle theory to explain why changing the temperature of a fluid can also change its density.
6. The density of a fluid usually decreases as the temperature rises. Explain how the behaviour of water differs from this pattern.
7. What is a hydrometer and what is it used for? Describe how to use a hydrometer.
8. Do hydrometers float higher in liquids that are denser or less dense? Make a Summary At the start of this unit; you created a table with some classmates to activate your knowledge of fluids (what they are, where they are found, how they are used, and some harmful effects of and to fluids). You have also developed a concept map as you worked through the...

...compute
i) The impeller speed for shockless entry,
ii) The input power required to run the pump at this speed if The mechanical
efficiency is 75%..
iii) The cost of running the pump for a month. Assume the pump is working for 8
hours per day and the electricity cost is RM6.50IkW/day.
(13 Marks)
CONFIDENTIAL
BAAIBAE/1011II/BAA2723
QUESTION 4
a) Prove that the Reynold's number is dimensionless and determine its value for water at
5°C flowing at a velocity of 2 m/s in a 5.08 cm diameter pipe. The dynamic viscosity is
1.519 x 103N.s/rn2.
(3 Marks)
b) Differentiate between the followings:
i) Geometric similarity
ii) Dynamic similarity.
(4 Marks)
c) A thin rectangular plate has a width, w and a height, h is located such that it is normal to
a moving stream of fluid. Assume that the drag, D that the fluid exerts on the plane is a
function of w and h, the fluid viscosity and density, Ii and p, respectively, and the
velocity, V of the fluid approaching the plate. Determine a suitable set of [I-terms to
study this problem experimentally.
(10 Marks)
d) A certain spillway for a darn is 20 m wide and is designed to carry a discharge of 125
m3 /s at flood stage. A 1:15 model is constructed to study the flow characteristics over
the spillway. By neglecting the effects of surface tension and viscosity;
i) Determine the required model width and flow rate.
ii) What...