Fluid Mechanics Principles & Applications

Educate.spsu.edu/faculty website SPSU e-mail “afm” Syllabus Notes - schedules Power Point

AFM

Outcomes Credits Text: Applied Fluid Mechanics, 6th

Edition, Robert Mott

AFM

Impacts: chemical manufacture, automobile systems, electrical generation, petroleum refining, water treatment

AFM

Extensive impact on everyday life• Home hot water system• Potable water• Waste water• Natural gas• HVAC• Refrigeration

AFM

Automobiles: fuel system, cooling system, brakes, power steering

Manufacturing: machine operations Farming: harvesting Construction: earth moving Mining Aircraft: control surfaces, landing gear

AFM

Mathematical approach → empirical approach

AFM: basics → working equation → application

Practice

Text examples, class examples, homework, tests

AFM

Learn A A basis for learning B• Read text

• Examples

• Homework

• Questions

• One minute paper

AFM

Learning Styles: Improves understanding and retention.

• Active – work problems, apply in lab, discuss in class, explain to someone.

• Visual – pictures, diagrams, demonstrations.

• Sequential – build knowledge in logical steps

AFM

“You can take this course one of two ways, seriously or again.” Dr. Neathery – Oklahoma State Univ.

AFM

Technicians: trained in set procedures; focus on how, what, when.

Engineers: learned basics; know why. Broader knowledge base.

AFM No cookbook Orderly/logical approach• Read carefully• Describe system• Sketch• Assumptions• Principles & working equations; tables & graphs• Solve• Reasonable

Approach

“Most difficulties encountered are due not to lack of knowledge, rather due to lack of organization (of what you know).” Dr. Cengel, N.C. State Univ.

AFM

Assumptions – reasonable

Solve Equation

Include units Consistent unit system Significant digits Equation is a representation of an

actual physical process, not an exercise in mathematics.

AFM

Reasonable result• Make sense?• Sign • Units• Magnitude

AFM

Presentations in real world: bosses & customers: logical, neat, & orderly

In AFM, to Instructor. Use same standard

AFM

Solid mechanics – objects stationary (statics) or moving (dynamics)

Fluid mechanics – fluids at rest or in motion

• Gas – fills available volume; no resistance to stress

• Liquid – limited volume; responds to stress by continuous deformation.

AFM

Gases – compressible Liquids – ordinarily incompressible.• Hydrostatics• Hydrodynamics: closed pipe, open

channel, external flow

Unit Systems

SI USCS

Properties

Characteristics of system Mass Weight Density Specific weight Specific gravity

Properties

Specific volume Ideal gas law Compressibility: bulk modulus Temperature• Engineering • Absolute

Viscosity

Resistance to deformation Proportionality constant Absolute Kinematic Saybolt viscometer Viscosity index

SAE viscosity

SAE10W-40• 10W for cold cranking engine• 40 for engine operating temperature

Viscosity

Temperature dependence• Liquid• Gas Shear dependence - rheology

Pressure Intensity of a force System property Vs reference: gage, atmospheric,

absolute Pascal’s Paradox Manometer• Barometer• U-tube

Examples

Mercury manometer is connected to an air duct to measure its insice pressure. The manometer deflection is 15mm. Atmospheric pressure is 100kPa. Find the duct’s absolute pressure. Hg = 13,600kg/m3.

Examples

Refer figure. Find the manometer deflection.

Pascal’s Law

An increase in pressure in an enclosed system will be transmitted throughout the entire system.

Hydraulic jack: Homework

Exert 100N on jack handle; support what force?

Homework

Oil with a specific gravity 0f 0.8 forms a layer 0.9m deep in an open tank that is otherwise filled with water having a depth of 2.10m. The water temperature is 10oC.

Calculate h Calculate P at the bottom of the tank

in gage pressure

Assignment

Mott: Chapters 1 & 2

QUESTIONS

References

Images & examples• Fluid Mechanics Fundamentals & Applications, 6th Edition, Cengel & Cimbala, McGraw Hill• Applied Fluid Mechanics, 6th Edition, Mott, Prentice Hall• Engineering Fluid Mechanics, 5th Edition Crowe, Elger, & Roberson, Wiley

Which of the problems were helpful? Why?