JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Pre-Requisites

Low speed aerodynamics

Course Objectives:

• Understand the effect of compressibility at high-speeds and the ability to make intelligent design decisions.
• Explain the dynamics in subsonic, transonic and supersonic flow regimes in both internal and external geometries.
• Analyze the airfoils at subsonic, transonic and supersonic flight conditions using the perturbed flow theory assumption.
• Formulate appropriate aerodynamic models to predict the forces and performance of realistic three-dimensional configurations.

Course Outcomes:

• Air compressibility and isentropic relations inform of speed
• Shock and expansion waves,
• Supersonic wind tunnel, nozzle design, flow visualisation technique

UNIT - I

INTRODUCTION TO COMPRESSIBLE FLOWS: Basic concepts: Introduction to compressible flow, brief review of thermodynamics and fluid mechanics, integral forms of conservation equations, differential conservation equations, continuum postulates, acoustic speed and mach number, governing equations for compressible flows.

UNIT - II

SHOCK AND EXPANSION WAVES: Shocks and expansion waves: Development of governing equations for normal shock, stationery and moving normal shock waves, applications to aircrafts, supersonic wind tunnel, shock tubes, shock polars, supersonic pitot probes; oblique shocks, governing equations, reflection of shock, Prandtl-Meyer expansion flow, shock expansion method for flow over airfoil, introduction to shock wave boundary layer interaction.

UNIT - III

ONE DIMENSIONAL AND QUASI ONE-DIMENSIONAL FLOW: Quasi one-dimensional flow: Isentropic flow in nozzles, area Mach relations, choked flow, under and over expanded nozzles, slip stream line. One dimensional flow: Flow in constant area duct with friction and heat transfer, Fanno flow and Rayleigh flow, flow tables and charts for Fanno flow and Rayleigh flow.

UNIT - IV

APPLICATIONS OF COMPRESSIBLE FLOWS AND NUMERICAL TECHNIQUES: Small perturbation equations for subsonic, transonic, supersonic and hypersonic flow; Experimental characteristics of airfoils in compressible flow, supercritical airfoils, area rule; Theory of characteristics, determination of the characteristic lines and compatibility equations, supersonic nozzle design using method of characteristics.

UNIT - V

EXPERIMENTAL METHODS IN COMPRESSIBLE FLOWS: Experimental methods: Subsonic wind tunnels, supersonic wind tunnels, shock tunnels, free-piston shock tunnel, detonation-driven shock tunnels, and expansion tubes and characteristic features, their operation and performance, flow visualization techniques for compressible flows.

R18 B.TECH AERONAUTICAL ENGG. III YEAR

TEXT BOOKS:

• 1. John D. Anderson, ―Modern Compressible flow with historical perspectiveǁ, McGraw-Hill Education, 3rd Edition, 2002.
• 2. John D. Anderson, ―Fundamentals of Aerodynamicsǁ, McGraw-Hill Education, 6th Edition, 2016.

REFERENCE BOOKS:

• 1. Ascher H. Shapiro, ―The Dynamics and Thermodynamics of Compressible Fluid Flowǁ John Wiley & Sons; Volume 1 ed. Edition, 1977.
• 2. Radhakrishnan Ethirajan, ―Gas Dynamicsǁ, John Wiley & Sons, 2nd edition 2010.
• 3. H W Liepmann and A Roshko, ―Elements of Gas Dynamicsǁ, John Wiley & Sons, 4th edition, 2003. R18 B.TECH AERONAUTICAL ENGG. III YEAR