MAE 101B ~ WELCOME

REQUIRED TEXTChapter 8: Internal Incompressible Viscous Flow - Sections 8.1-8.8

Chapter 9: External Incompressible Viscous Flow – Sections 9.1-9.8

Chapter 11: Introduction To Com- pressible Flow – Sec. 11.1-11.4

Chapter 12: Compressible Flow Sections 12.1-12.5

MAE 101B

exploring a series of paradoxes…

Paradoxes:For internal flows:Pipe flow theory predicts p proportional to uavg but for most

experiments not so!For external flows: Usually an increase in velocity accompanied by an increase in

drag, but not always!Usually surface roughness increases drag, but not always!Usually streamlining decreases drag, but not always!For compressible flows:Usually reducing duct area increases velocity, but not always!Usually friction results in velocity decrease, but not always!Usually heat addition results in temperature increase,

but not always!

1887-1922

1923-1943

HYDRAULICS

1938

1950-1965

Hydor = water + aulos = tube~200 BC term hydraulics coined

Hydrodynamics- term introduced in 1733 by Daniel Bernoulli to comprise the two sciences of hydrostatics and hydraulics.

Fluide = that which flows

HYDRAULICS

1934

1744 D’Alembert’s Paradox

1938

In 1744 D’Alembert, assuming potential flow, deduced his famous paradoxical result that a moving sphere does not encounter any resistance to its motion. D’Alembert realized the contradiction between his mathematical result and experimental fact and knew that the premises of the theory must be at fault. (Indeed he consistently emphasized the supremacy of experiment over theory and his further investigations were mainly experimental).

Tietjens and Prandtl ~ Fundamentals of Hydro- and Aeromechanics

1934

1950

In Summary ~ Hydraulics~ a large empirical subject mainly based on formulae and data sheets developed in light of experiments and experience by civil and mechanical engineers.

~ valuable for dealing with problems arising inthe design of fluid machinery, ships, piping systems, etc.

~ provided little theory from which formulae could be justified and confidently generalized.{There is nothing more practical than a good theory - Hoerner}

In Summary ~ Classical Hydrodynamics

~ given certain seemingly reasonable assumptions, governing equations known, so much mathematics can be brought to bear.

~ reasonable accurate description for the motion of waves, jets, and lift if no separation.

~ lift is predicted if circulation is postulated but can say nothing about how circulation arose, predicts no drag, predicts linear dependence of pressure and Uavg

in pipe flow.

aside arguably one of the finest fluids book

1738

An Anatomical Study of the Motion of the Heart and of the Blood in Animals – William Harvey (1628)

“When an artery is punctured the blood would be seen spurting with violence.”

“projected now to a greater, now to a lesser distance, the tallest jet occurring when the heart contracts

1729 – Bernoulli reasoned that he height of the spurting blood was a direct measure of its pressure in the artery. Bernoulli punctured the wall of a pipe with

a small hole and attached a glass straw. The height of the water in the straw he realized is a measure of the flowing water’s pressure. (blood pressure was

measured this way until 1896 when sphygmomanometer was invented)

Daniel Bernoulli (1700-1782) Hydrodynamica• published in 1738• contains correct analysis of water

flowing from a hole in a container• bases of kinetic theory of gases• force of jet on inclined plane• Bernoulli’s Equation

Johann Bernoulli – Hydraulica• printed in 1739• predated 1732• largely based on Hydrodynamica• author: Johann Bernoulli (father)

Despondent over his father’s plagiarism: “I have no longer been able to persuade myself to work on anything

mathematical. My entire remaining pleasure is to work on some projectson the blackboard now and then for future oblivion.”

MAE 101B SUMMER II – 2006BATTLE RYTHYM

CLASS SYLLABUS

Lectures: M, W, F: 6:00 – 7:50Rm 2204; Warren Lecture Hall

 Instructor: Dr. Jim Rohr (619) 553-1604

james.rohr@navy.milOffice Hours – after class or by appt.

 Teaching Assistant: Julie Crockett

jcrockett@ucsd.eduDiscussion Sessions: Thurs. - Rm 312, EBU2; 4:00 – 6:00 PMWeds. / Fri. – after lectureRm 2204; Warren Lecture Hall8:00 – 9:00 PM

 

CLASS SYLLABUS

Prerequisites: MAE 110A – Thermodynamics

MAE 101A – Introductory Fluid Mechanics

Textbook: Introduction to Fluid Mechanicsby R.W. Fox, A.T. McDonald, P.J. PritchardJohn Wiley and Sons, Inc., Sixth Edition (2004)

 Website: See Class Web Sites at:

MAECOURSES.UCSD.EDUhttp://maeweb.ucsd.edu/Lecture notes, assignments, homework solutions, templates for homework format.

http://maecourses.ucsd.edu

CLASS SYLLABUSHomework: Homework will be assigned every Monday and due the following Friday. Homework must be submitted before the beginning of class. No late Homework accepted. Each homework problem will be graded thusly: 1 pt per question awarded if “reasonable” effort. Most of the problems on the quizzes, every Mon. ( or Weds.),and final exam will be similar to the homework assignments, examples in book and the problems I do in class. Homework problems will be reviewed during Julie’s office hours and posted on the website the evening that they are due.

CLASS SYLLABUS

Quizzes: Every Monday during last 1/2 hour of class based on the previous homework. The tests will be close book and closed notes but a sheet of equations from the relevant chapter (and posted on the web) will be provided. Each test will be worth 15 points (60 points total).

CLASS SYLLABUS

Final Exam will be comprehensive and based primarily on the homework.

You can bring two pages (9 ½” x 11”) of equations, otherwise closed book and closed notes.

Final is worth 30 points of your total grade.Half on Chap. 12 / half on Chapters 8, 9, 11

CLASS SYLLABUS

Grading:Home Work (4): 10%Quizzes (4): 60%Exam (1): 30%

CLASS SYLLABUS

Week 1: Aug. 7, 9, 11 – Chapter 8, Sections 8-1 to 8-8

Week 2 & 3: Aug. 14, 16, 18, 21, 23, 25 – Chapter 9, Sections 9-1, 9-2, 9-4 to 9-9

Week 4: Aug. 28, 20, Sept 1 – Chapter 11, Sections 11-1 to 11-5Chapter 12, Sections 12-1 to 12-2

Week 5: Sept 6, 8 – Chapter 12, Sections 12-3 to 12-5

Sept. 9: Final Exam(Blue indicates quiz day, red indicates final exam day)

RECOMMENDED BACK-UP

Other texts: Fluid Mechanics

– White (McGraw Hill)Boundary-Layer Theory

– Schlicting (McGraw – Hill)Shape and Flow

- Shapiro (Anchor Books)Elements of Gas Dynamics

- Liepmann & Rochko (Wiley)Gas Dynamics

- John (Allyn andBacon)Introduction to Flight

- AndersonEngines, Energy and Entropy

- Fenn (Freeman and Company)

Intro. To Fluid Mechanics- Nakayama & Boucher (Arnold)

“Although fluid mechanics is a challenging and complex field of study, it is based on a small number of principles, which in themselves are relatively straight forward. The study of fluid mechanics is undoubtedly difficult but it canalso become a profound and satisfying pursuit for anyone with a technical inclination.” Alexander J. Smits

WHERE ISWALDO?

aside….

“The unsung hero of human history

was, of course,…

The Brain of Drains, the Hub of Tubs, the Power of Showers, the Brewer of Sewers …

the humble plumberW. Hodding Carter

if I could not be a prince, I would rather be a plumber

Edward – Prince of Wales

• plumbing around at least 7000 years• 5000 BC. bamboo pipes in China• 3000 BC. earthenware pipes in India & Pakistan• 500 BC lead pipes in Greece• plumbum Latin word for lead / plumarius ~Roman word for plumber (100 AD - 1 million people in Rome : ~ 300 gallons per day per household)

• 1128 - lead plumbing through Paris• 1237 - lead (and wood) plumbing through London• 1870 – modern toilet

(~ 2 million children in India alone die of diseases due in part to poor sewage disposal)

THE END

In A.D. 97, Rome’s great water commissioner Sextus Julius Frontinus boasted:

“Will anybody compare the idle pyramids or those other useless though much renowned works of the Greeks with these aqueducts?”

• Water flows downhill, never uphill

• The greater the diameter, the larger amount of water a pipe can deliver

Fluid mechanics known by Romans: