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Blade Designs using Radial Equilibrium Theory. P M V Subbarao Professor Mechanical Engineering Department. A Choice of Designs with Stable Operation of A Machine. Major Modules in Turbine Blades. Twisted Blades for Radial Equilibrium of Fluid. Lessons from Nature.
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Blade Designs using Radial Equilibrium Theory P M V Subbarao Professor Mechanical Engineering Department A Choice of Designs with Stable Operation of A Machine
General Rules for Selection of Whirl Component : 1 • Free Vortex Whirl:
General Rules for Selection of Whirl Component : 2 • Forced Vortex Whirl :
HybridModels for Whirl Velocity Inlet Exit • Weighted mean of free and forced vortices
Biased Models for Whirl Velocity • General Whirl Distribution
Radial Variation of Whirl Velocity Intake Discharge
Radial Variation of Flow Velocity in Advanced Turbines Discharge Intake
Radial Variation of Mass flow rate Intake Discharge
Other Physics Based Models • Uniform distribution of mass flow rate. • Uniform distribution of forces. • Uniform distribution of torque.
Two Major Steps in Creation of Turbine blade • Develop a new blade designs based on Ideal Fluid Conditions – A generalized Procedure. • Modify the design details for Real Fluid Conditions.
Calculation of lift force • The lift force L is determined by integration of the measured pressure distribution over the airfoil’s surface. where, pi= surface pressure distribution , p = pressure in the free-stream U∞ = free-stream velocity, = air density (temperature), c = airfoil chord
Definition of lift and drag Coefficients Lift and drag coefficients Cland Cdare defined as:
Can We Identify the Cause? Which is best for describing how aircraft get the needed lift to fly? Bernoulli's equation or Newton's laws and conservation of momentum?
An Engineering Domination to Natural ExpertsFlying Faster ??????????????? Isn’t it very easy to do?????
The Shocking News • The New York Times wrote that maybe • 1 million to 10 million years they might be able to make a plane that would fly ?!?!?! • People had dreamed of flying for many years. • The United States Army was trying to develop an airplane in 1903, but the plane wouldn't fly. • Only eight days later two men were successful in flying the first manned plane. • They were Wilbur Wright and his younger brother, Orville. • Controlled, powered flight had seemed impossible until Orville Wright took off on the 17th December 1903.
Kate Carew Interviews the Wright Brothers • “Are you manufacturing any racing machines?” • “Not just now, but we intend to.” • “How much can I buy one for?” • “Seven thousand five hundred-dollars.” • “Is that all? It doesn’t seem like an outside price for a perfectly good airship?” • “Airship!” shouted the Wright brothers indignantly. • “Is that the wrong word?” • “An airship,” said Wilbur contemptuously, “is a big, clumsy balloon filled with gas.” • “Well, I don’t see why your biplane shouldn’t be called an airship, too.” • “It’s a flying machine,” said Wilbur. • “The name we prefer is ‘flyer,’” said Orville. • “An airship would cost $50,000,” said Wilbur. • “More like $150,000,” said Orville, and they argued the question.
http://www.wrightbrothers.org/History_Wing/Aviations_Attic/Carew_Interview/Carew_Interview.htmhttp://www.wrightbrothers.org/History_Wing/Aviations_Attic/Carew_Interview/Carew_Interview.htm Transformation of an Airship into a Flying Machine
19th Century Inventions Otto Lilienthal H F Phillips