{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Final Review Questions

# Final Review Questions - CENG l OlA 2009 SAMPLE PROBLEMS...

This preview shows pages 1–2. Sign up to view the full content.

-- CENG lOlA - 2009 SAMPLE PROBLEMS D.M1LLER During the last week of class, on Tues and Wed, we will review the course material and go over sample problems. Please bring your texts to class. I have sketched some problems below which are typical of the type which may appear on the fmal. Please come to class prepared to answer a few of these, of your choice, if you are called upon. We will only have time to outline the approach you would take in most cases, i.e. indicate the method and which equation you would use, not to do the details with numbers. You may assume you would be given appropriate dimensions, properties, empirical CD, and equations or that the final is open book. Example Questions I. Answer Briefly~ Since a rough surface increases friction and a turbulent flow has a larger effective viscosity than a laminar flow, which should also increase friction shear forces, discuss briefly why dimpled golfballs have less drag and therefore go farther than smooth balls of the same size and weight. Why does streamlining a body sometimes reduce and sometimes increase the drag? 2. Answer Briefly: List the assumptions necessary to obtain the Navier-Stokes equations What is the difference between an Eulerian and a Lagrangian description of fluid mechanics, and what is the difference between a control system and a control volume. What is the buoyancy force due to? From what Law is the extended Bernoulli equation derived? When is it valid only along a streamline? 3. Answer Briefly: Discuss why does the water jet goes much fwther when you place your thumb over the garden hose exit and decrease the exit area? What are the Reynold's stresses, where do they come from, and when are they important. 4. Estimate the fluid velocity for transition from laminar to turbulent flow if the pipe diameter is I cm and the fluid is: (a) water; (b) air . Does the result depend on whether the pipe is vertical or horizontal? 5. Derive a relation between the absolute pressure at any altitude h and the absolute pressure at sea level, given as P = Po at y = 0 . Assume air is an ideal gas P = pRT , and assume the atmosphere is isothermal (RT = constant).

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 2

Final Review Questions - CENG l OlA 2009 SAMPLE PROBLEMS...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online