Aerodynamics-II

One dimensional compressible flow 1-DFlow equations, Velocity of sound, Isentropic subsonic and supersonic flows through converging and diverging passages, Supersonic flow through constant area ducts (Fanno flow), Rayleigh flow & flow through C-D nozzle. Area-velocity relations, Mach wave, Mach angle. Critical Mach number, critical pressure and & drag divergent, Area rule for design.

2-D supersonic flow Two-dimensional flow equation, supersonic flow past wedges and concave corners, Normal shock & oblique shock waves, Normal shock relations & Oblique shock relations, Hodograph shock polar. Strong, weak and detached shocks, Prandtl-Meyer expansion flow past two dimensional concave corners, Expansion hodograph, Reflection of shocks and expansion waves Method of characteristics.

Differential Equation of motion Steady compressible flows, Small perturbation potential equations, Solution for subsonic and supersonic flow, Prandtl-Glauert transformation relation for subsonic flows. Linearized and exact 2- D supersonic flows theory and its application for calculation of lift and drag and pitching moments center of pressure, Method of characteristics, Prandtl-Glauert correction. Compressibility effects on aerodynamic coefficients.

• Aerodynamic Testing Aerodynamic testing facilities for different speed regimes, low speed wind tunnels, closed and open
• circuit tunnels. Main features of Subsonic, supersonic and transonic tunnels, shock tunnels, Instrumentation and calibration of test section. Testing procedure, data reduction, blockage effects and boundary layer corrections, correction to lift and drag,
• Measuring devices in Test Section Pitot static tube, yaw probes, five-hole probe, hot wire anemometers. Flow visualization techniques oil flow, tuft survey and smoke. Flow field pressure measurements, Schlieren, shadowgraph and interferometer technique, laser Doppler and PIV technique.

• Propellers momentum and blade theories Airfoil characteristics in forward flight, use of propeller charts, Effect of solidity, profile drag, compressibility etc., and blade area required, number of Blades, Blade form. Selection and performance of fixed and variable pitch propellers, configurations based on torque reaction-Jet rotors and flapping and feathering, Rotor controls and various types of rotor, Blade loading, Power losses and Rotor efficiency.
• Aerodynamics of Rotor Blade Elementary concept of helicopter hovering and climbing, helicopters Methods of control collective and cyclic pitch changes - Lead - Lag and flapping hinges, Blade stall, maximum lift of the helicopter calculation of Induced Power, High speed limitations; parasite drag, power loading, ground effect.