Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy.

Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.

Like this presentation? Why not share!

No Downloads

Total views

1,551

On SlideShare

0

From Embeds

0

Number of Embeds

30

Shares

0

Downloads

79

Comments

0

Likes

4

No embeds

No notes for slide

- 1. MET 306 Fluid Mechanics Lecture # 111/5/2012
- 2. ObjectiveDetermine Unit and DimensionsIdentify the key fluid properties used in the analysis of fluid behaviorCalculate common fluid properties given appropriate informationExplain effects of fluid compressibilityUse the concept of viscosity and surface tension11/5/2012
- 3. Unit and DimensionsA dimensions is used to measured the physical quantity with out numerical value.A unit is the way to assign a number to dimension L= length is dimension m= unit used for lengthTwo system of the fundamental dimension 1. FLT 2. MLT11/5/2012
- 4. Unit and Dimensions11/5/2012
- 5. Unit and DimensionsExample: m L 1 Velocity : LT s T Most of the fluid problem required the basic fundamental dimension witch (MLT) 2 Force : F ma MLT The equation of the velocity for uniformly acceleration body V Vo at Where: Vo is the initial velocity a is the acceleration11/5/2012 t is the time
- 6. Unit and DimensionsDimensionally homogeneousAll theoretically derived equation are dimensionally homogeneous that is thedimensions of the lift side of the equation must be the same as those on the right side. V Vo at 1 1 2 LT LT LT T 1 1 1 LT LT LT 1 1 LT 2 LT The equation of the velocity for uniformly acceleration body is dimensionally homogeneous and the 2 is a constant number11/5/2012
- 7. Unit and DimensionsDimensionally homogeneous Check whether this equation is dimensionally homogeneous or NOT 1-Equation of a freely falling body 2 d 16 . 1t Where d= distance t= time 2-Volume rate flow equation Where Q 0 . 61 A 2 gh Q= Flow rate A= Area g= gravity h= height11/5/2012
- 8. Systems of UnitsInternational System (SI)British gravitational system(BG)11/5/2012
- 9. Measures of Fluid Mass and Weight Density The density of the fluid designated by Greek symbol (ρ) Defined as a mass per unit volume Used to characterize the mass of fluid BG= slugs/ ft3 and SI= kg/m3 Specific Weight The specific weight of the fluid designated by Greek symbol (γ) Defined as weight per unit volume Used to characterize the weight of the system BG= lb/ ft3 and SI= N/m3 Specific Gravity The specific gravity of the fluid designated by SG Defined as a ratio of the density of the fluid to the density of the water The density of the water @ 4oC is BG=1.94 slugs/ft3 and SI=1000 kg/m3 11/5/2012
- 10. Measures of Fluid Mass and WeightSpecific Gravity (Example) Calculate the density of the mercury in two system BG and SI by knowing the SGmercury @ 4oC is 13.5511/5/2012
- 11. Ideal Gas Law Gas are highly compressible in comparison to liquid, So from the Ideal gas law change in the temperature or the pressure of the gases can directly change the density. p R T Where p is the absolute pressure, ρ is the density, T is the absolute temperature and R is gas constant R=R/m R is universal gas constant 8314.3J/kg mole K m is the molar mass11/5/2012
- 12. Ideal Gas LawExample The absolute pressure and temperature of a gas in large chamber are found to be 500 kPa and 60oC respectively. Find the density if the air has m =28.9711/5/2012s
- 13. Viscosity Dynamic viscosity BG and SI du Slug/ft s Kg/ms dy See Figure 1.1 SI Kinematic Viscosity v m2/s11/5/2012
- 14. Viscosity11/5/2012
- 15. Viscosity Example Determine the value of the Reynolds number using SI system for fluid with viscosity of 0.38 N.s/m2 and specific gravity of 0.91 flow into pipe with diameter of 25 mm with velocity of 2.6 m/s.11/5/2012
- 16. 11/5/2012
- 17. 11/5/2012
- 18. Surface Tension At interface between a liquid and the gas forces develop in the liquid surface which case the surface to behave as “skin” or “membrane”11/5/2012
- 19. Surface Tension(σ) The pressure inside the drop can be calculated using free body diagram . The force developed around the edge due to the surface tension is 2πRσ this force must be balance by the pressure difference 2 2 R p R11/5/2012
- 20. Surface Tension(σ) 2 R 2 ϴ R h 2 R cos 2 R h h11/5/2012
- 21. Surface Tension(σ)Example What diameter of clean glass tubing is required to rise water at 20oC in tube to 1mm. Where σ of water is 0.0728 N/m and the θ =0.11/5/2012

No public clipboards found for this slide

×
### Save the most important slides with Clipping

Clipping is a handy way to collect and organize the most important slides from a presentation. You can keep your great finds in clipboards organized around topics.

Be the first to comment