AE 215 AERODYNAMICS II YEAR AERO

UNIT I INTRODUCTION TO LOW SPEED FLOW Euler equation(3d), Incompressible Bernoulli equation, Circulation and vorticity, Green’s lemma and stoke’s theorem, barotropic flow, Kelvin’s theorem, streamlines, stream function, irrotational flow, potential function, equipotential function, flownet, elementary flows and their combinations. Example problems on conservation equations.

TEXT BOOKS Anderson. J.D “ Fundamentals of Aerodynamics” (Unit I,II III, IV) Clancey. L.J “Aerodynamics”, (Unit I, II, III, IV, V)

REFERENCE BOOKS Karamcheti K., (1966), Principles of Ideal-Fluid Aerodynamics, John Wiley & Sons Inc (Units: I, II, IV & V) Bertin J.J., “Aerodynamics for Engineers”, Prentice Hall; 6th edition, 2013. (Units: I, II, IV &V) Houghton, E.L., and Caruthers, N.B., "Aerodynamics for Engineering students",Edward ArnoldPublishers Ltd., London, 1989. (Units: I, II, III, IV & V) Kuethe A. M. and Chow C.-Y., “Foundations of Aerodynamics”, John Wiley & Sons Inc. ., 5th Edition, 1997. (Units: I, II, IV & V) Kundu P.K. & Cohen I.M., (2008), Fluid Mechanics, Elsevier Inc. (Units: I, II& V)

“Father of Modern Aerodynamics“ The term “Aerodynamics” is generally used for problems arising from flight and other topics involving the flow of air. -Ludwig Prandtl 1949

Fluid Dynamics The study of dynamics of both liquids and gases called Fluid Dynamics. It is broadly classified into Hydro dynamics – Flow of liquids Gas Dynamics- Flow of gases Aerodynamics- Flow of air

What is the difference between gas and air? 'Gas' is a one of the many states of matter. The other common of matter are 'solid', 'liquid' and 'plasma'. 'Air' as in the atmosphere we live in and breathe, on the Earth, is a mixture of various gases such as nitrogen, oxygen, carbon dioxide, and so on. Thus, air is gaseous.

Steady & Unsteady Flow Steady Flow Fluid characteristics velocity, pressure, density at a point do not change with respect to time. Unsteady Flow Fluid characteristics velocity, pressure, density at a point changes with respect to time.

Types of Flow Laminar flow Turbulent flow Transitional flow

Quiz 1 Flow through pipe when valve is being opened is a) Steady b) Unsteady c) Circulation d) Vortex

Compressible & Incompressible Flow Density of a fluid changes from point to point Incompressible Flow Density of a Fluid will not change from point to point

Applications of Aerodynamics Internal Aerodynamics Internal Flow over ducts To calculate flow properties inside engine Flow through pipes Flow inside wind tunnel External Aerodynamics Calculation of Lift & Drag To estimate wind force over buildings, ships To calculate Aerodynamic heating of flight vehicle

Two mark Questions Differentiate compressible and Incompressible flow Define Stream line flow Mention the properties of stream line flow Give examples for path line and Streak line Jot down the various applications of Aerodynamics State First Law of Thermodynamics Which law satisfies Conservation of Momentum Sate Conservation of Energy What is the principle of Conservation of Mass

Multiple Choice Questions 1. All real fluids are __________to some extent a) Compressible c) Transitional b) Incompressible d) Turbulent 2. According to ISA (International Standard Atmosphere) a decrease in temperature indicates __________ a) Decrease in altitude b) Increase in altitude c) No change in altitude d) Change in Angle of Attack

3. The flow in which each liquid particle has a definite path and their path do not cross each other is called ___________ a) One dimensional Flow b) Uniform Flow c) Steady Flow d) Stream line Flow 4. The flow in which conditions do not change with time at any point is known as ____ a) One dimensional Flow b) Uniform Flow c) Steady Flow d) Stream line Flow

5. A Stream line is defined as the line _________ Parallel to Central Axis flow Parallel to outer surface of pipe Equal Velocity in flow Pressure drop is uniform 6. Continuity Equation is connected with Compressibility of Fluids Steady/Unsteady Flow Conservation of Mass

World Around Us Russian Plane Crash

Russian Air Crash 25 December 2016 Site Black Sea, approx 1.5 kilometres (0.9 mi) off the coast from Sochi, Russia Aircraft type Tupolev Tu-154B-2 Operator Russian Air Force Registration RA-85572 Flight origin Chkalovsky Airport, Russia Stop over Sochi International Airport, Sochi, Russia Destination Khmeimim Air Base, Latakia, Syria

Session Objective Stream line flow Streak line Path line Properties of Stream line flow

Stream line A Stream line is an imaginary line drawn in the flow field such that velocity vector at any point on the line is always tangential to the flow. PROPERTIES : The fluid properties cannot cross each other The flow ratio between any two stream lines remains same through out the flow. The difference between any stream function value for any two stream lines will be equal to volume flow rate of the fluid between those two stream lines.

Solid blue lines and broken grey linesrepresent the streamlines. The red arrows show the direction and magnitude of the flow velocity. These arrows are tangential to the streamline. The group of streamlines enclose the green curves ( and ) to form a stream surface.

Streamline, pathline, streakline defined to describe a flow and visualise it.

Path line Path line indicates the direction of velocity of fluid particle at a consecutive instant of time. In steady flow path line and Stream line are same.

Streak line Streak line is the locus of all points that have gone through a given point in the flow.

Conservative Laws Conservation of Mass- Newton First Law Conservation of Momentum- Newton Second Law Conservation of Energy- First Law of Thermodynamics

Control Volume Control volume has a fixed boundary. Mass, Momentum and Energy are allowed to cross the boundary. Control Surface The boundary of the control volume is referred to as Control Surface

Puzzle As shown in the image below, group of fishes are swimming from left to right. By moving just three matchsticks, can you make fishes from right to left? 

Solution

Puzzle 2 Move 4 matchsticks to form 5 triangles. The triangles do not have to be equal in size. All matchsticks must be flat on the surface.

Solution

Multiple Choice Questions 1) The path traced by as single particle is called ____ A) Path line B) Stream line C) Streak line 2) Bernoulli's equation deals with law of conservation of _____ A) Mass B) Energy C) Momentum