Presentation on theme: "An Essential Engineering for Human (Internal & External) Comforts…… P M V Subbarao Professor Mechanical Engineering Department I I T Delhi ORIGIN & SCOPE."— Presentation transcript:
An Essential Engineering for Human (Internal & External) Comforts…… P M V Subbarao Professor Mechanical Engineering Department I I T Delhi ORIGIN & SCOPE OF VISCOUS FLUID FLOWS
Hans Albert Einstein (May 14, 1904 – July 26, 1973) Hans Albert Einstein was a Swiss-American engineer and educator. He was an avid sailor, frequently taking colleagues and family out for excursions on the San Francisco Bay. On his many field trips and academic excursions, he took thousands of pictures, many of which he developed himself and presented as slide shows. In tribute to Einstein's lifelong contributions to the field, his former graduate students published a book of research in his honor in 1972, Sedimentation: Symposium to Honor Professor H.A. Einstein. In 1988, the American Society of Civil Engineers created the Hans Albert Einstein Award to recognize outstanding achievements in erosion control, sedimentation and/or waterway development.
Inspiring Words : Albert Einstein When asked what he wished to become, as a young man, Nobel Laureate Albert Einstein said, "I want to become a useful person, not a successful person." Asked what he meant by it, the eminent physicist replied, "A successful person is one who takes from society more than what he gives it. A useful person is one who gives the society more than what he takes from it."
Albert Einstein`s Opinion on Best Theory A Theory is more impressive or useful –the greater the simplicity of its premises is, –the more different kinds of things it relates, –and the more extended is its area of applicability.
The Law of Learning one fourth from the teacher, one fourth from own intelligence, one fourth from classmates, and one fourth only with time. Mahabharath
Why Humans Study/ Show Great Concern about Fluid Flow in his World of Existence ?????
The Most Ancient (Materialistic) use of Fluid Flows
Technology Vs Viscous Fluid Flows Water Mills Wind Mills Heat Engines Steam /gas turbines Mechanical Machine free?
Development of Fluid Flow Systems using a selected combination of Forces Systems only due to Body Forces. Systems due to only normal surface Forces. Systems due to both normal and tangential surface Forces. –Only mechanical forces. –Only electrical forces. –Electro-kinetic forces. –Thermo-dynamic Effects (Buoyancy forces/surface )….. –Physico-Chemical/concentration based forces (Environmental /Bio Fluid Mechanics
Major Flow Systems due to Mechanical Forces : Level 1 Incompressible – A vector dominated….. Compressible – Both vector and scalar ….
1930’s Flying Story Cruising at High Altitudes ?!?!?! Aircraft were trying to approach high altitudes for a better fuel economy. This led to numerous crashes for unknown reasons. These included: The rapidly increasing forces on the various surfaces, which led to the aircraft becoming difficult to control to the point where many suffered from powered flight into terrain when the pilot was unable to overcome the force on the control stick. The Mitsubishi Zero was infamous for this problem, and several attempts to fix it only made the problem worse. In the case of the Super-marine Spitfire, the wings suffered from low torsional stiffness.
The P-38 Lightning suffered from a particularly dangerous interaction of the airflow between the wings and tail surfaces in the dive that made it difficult to "pull out“. Flutter due to the formation of thin high pressure line on curved surfaces was another major problem, which led most famously to the breakup of de Havilland Swallow and death of its pilot, Geoffrey de Havilland, Jr.
Major Flow Systems due to Mechanical Forces : Level 2 Laminar – Absolutely Deterministic … –The structured tensors…. –The relations among tensors, vectors & Scalars –Advanced Vector calculus… Turbulent – Statistically Deterministic…. –Concept of ensemble/temporal/spatial averaging. –Creation of more tensors to develop deterministic approach… –The issue of closure.