A Design Philosophy through Accounting/Balancing/ Conservation …. P M V Subbarao Professor Mechanical Engineering Department I I T Delhi Rothalpy Based Design of Turbines

Conservation of Rothalpy A cornerstone of the analysis of steady, relative flows in rotating systems has, for many years, been the immutable nature of the fluid mechanical property rothalpy. "In a moving passage (Flow Path) the rothalpy is therefore constant provided: – the flow is steady in the rotating frame; –no friction from the casing; –there is no heat flow to or from the flow. or

Ideas for creation of a variety in turbo-machine. Clues for Creation of Basic Variations in Fluid Flow Paths Infusion of more Euler concept:

Blade Velocity Vs Tangential Component of Fluid Velocity UbUb UbUb ViVi V ai V fi V ri In maridional plane at mean radius of rotor

UbUb ViVi V ai V fi V ri UbUb ViVi V ai V fi V ri ViVi UbUb V ai V fi V ri Variations in Inlet Flow Geometry

Relative Angular Velocity Constant in an ideal turbo-machine

For stator U blade =0 For rotors : For a true axial flow machines: U blade constant throughout the flow path Behavior of Fluid along Flow Paths in Stator Vs Rotor

Blade Velocity Vs Tangential Component of Fluid Velocity UbUb UbUb ViVi V ai V fi V ri In maridional plane at mean radius of rotor & inlet

UbUb V  iV  i V ai V fi V ri UbUb V  iV  i V ai V fi V ri V  iV  i UbUb V ai V fi V ri

Relative Angular Velocity Constant in an ideal turbo-machine

Evolution of Relative Velocity Along Flow Path

For stator path : U blade =0 For rotor Paths : For a true axial flow rotor paths: U blade constant Classification of Isentropic Expansion Paths

Turbo-machines working with Vapors/Gas For an ideal gas:

For simple compressible fluid: Like Inert Gas Turbo-machines working with Perfect Gas

The Fourth Generation Nuclear Power Plants

An Advanced Nuclear Power Plant

The Ultimate Importance of Invariant Property : Rothalpy

Selection of Stator-Rotor Combinations

From Books of Sir Charles Parson In 1884 or four years previously, I dealt with the turbine problem in a different way. It seemed to me that moderate surface velocities and speeds of rotation were essential if the turbine motor was to receive general acceptance as a prime mover. I therefore decided to split up the fall in pressure of the steam into small fractional expansions over a large number of turbines in series, so that the velocity of the steam nowhere should be great. A moderate speed of turbine suffices for the highest economy.

This principle of compounding turbines in series is now universally used in all except very small engines, where economy in steam is of secondary importance. The arrangement of small falls in pressure at each turbine also appeared to me to be surer to give a high efficiency. The steam flowed practically in a non-expansive manner through each individual turbine, and consequently in an analogous way to water in hydraulic turbines whose high efficiency at that date had been proved by accurate tests.

Classification of Steam Turbine Flow Paths

Selection of Stator-Rotor Combinations

How to Execute Conservation of Rothalpy ?? Enthalpy Kinetic Energy Velocity Vector Field Fluid Dynamics Generation of Change in rate of angular momentum (An Action) Who Will take the Reaction ??? Shaft Torque is the final need as Reaction