ME4438 Computational Fluid Dynamics End of Semester Exam Paper 2019-20 QUESTION 4. (30 marks total) 4(a),...
Fantastic news! We've Found the answer you've been seeking!
Question:
Transcribed Image Text:
ME4438 Computational Fluid Dynamics End of Semester Exam Paper 2019-20 QUESTION 4. (30 marks total) 4(a), (8 marks) Briefly explain, within the context of a turbulent flow, what is meant by; A turbulent eddy; A length scale; A frequency: The energy cascade. 4(b). (6 marks) The transient 3D, laminar flow Navier-Stokes equation in the x-direction is given by 8( 2 + (puv) = - +V (\u) at ax Page 5 of 5 Describe how the technique known as direct numerical simulation goes about solving this equation for a turbulent flow. 4(c). (12 marks) The x-momentum equation for ID (in the x-direction), transient, incompressible flow is given by (pu) (puu) dp a'u dx ax di dx Use the technique known as Reynolds decomposition and time averaging to formulate a version of the above equation which is applicable to a turbulent flow. Clearly indicate which terms in the time averaged version are called the Reynolds stresses. 4(d), (4 marks) The eddy viscosity can be written in the following form; , =cpV, where c, is a constant, V, is the velocity associated with the eddy movement around the flow field, and I, is the distance travelled by an eddy before it dissipates its energy in another part of the flow field. Starting from the equation given for ,, and using an order of magnitude analysis, show that the eddy viscosity can be expressed in terms of the eddy kinetic energyk, and the viscous dissipation rate &. ME4438 Computational Fluid Dynamics End of Semester Exam Paper 2019-20 QUESTION 4. (30 marks total) 4(a), (8 marks) Briefly explain, within the context of a turbulent flow, what is meant by; A turbulent eddy; A length scale; A frequency: The energy cascade. 4(b). (6 marks) The transient 3D, laminar flow Navier-Stokes equation in the x-direction is given by 8( 2 + (puv) = - +V (\u) at ax Page 5 of 5 Describe how the technique known as direct numerical simulation goes about solving this equation for a turbulent flow. 4(c). (12 marks) The x-momentum equation for ID (in the x-direction), transient, incompressible flow is given by (pu) (puu) dp a'u dx ax di dx Use the technique known as Reynolds decomposition and time averaging to formulate a version of the above equation which is applicable to a turbulent flow. Clearly indicate which terms in the time averaged version are called the Reynolds stresses. 4(d), (4 marks) The eddy viscosity can be written in the following form; , =cpV, where c, is a constant, V, is the velocity associated with the eddy movement around the flow field, and I, is the distance travelled by an eddy before it dissipates its energy in another part of the flow field. Starting from the equation given for ,, and using an order of magnitude analysis, show that the eddy viscosity can be expressed in terms of the eddy kinetic energyk, and the viscous dissipation rate &.
Expert Answer:
Related Book For
Business Statistics
ISBN: 9780321925831
3rd Edition
Authors: Norean Sharpe, Richard Veaux, Paul Velleman
Posted Date:
Students also viewed these computer network questions
-
QUIZ... Let D be a poset and let f : D D be a monotone function. (i) Give the definition of the least pre-fixed point, fix (f), of f. Show that fix (f) is a fixed point of f. [5 marks] (ii) Show that...
-
Let A, B be sets. Define: (a) the Cartesian product (A B) (b) the set of relations R between A and B (c) the identity relation A on the set A [3 marks] Suppose S, T are relations between A and B, and...
-
If A and B are mutually exclusive events and P(A) = 0.2 and P(B) = 0.7, then P(A and B) is?
-
Force 1 acts on a particle and does work W1. Force 2 acts simultaneously on the particle and does work W2. The speed of the particle does not change. Which one of the following must be true? (a) W1...
-
The following are Hofstedes dimensions of culture, except for ___________. Power distance Femininity versus masculinity Paradoxicality Individualism versus collectivism
-
A 30-kg child slides down the amusement-park wave slide shown in Figure P9.29. When they are \(0.95 \mathrm{~m}\) above the water level their speed is \(2.2 \mathrm{~m} / \mathrm{s}\). At the top of...
-
North Company has completed all of its operating budgets. The sales budget for the year shows 50,000 units and total sales of $2,000,000. The total unit cost of making one unit of sales is $22....
-
In the video below, critique the introduction and conclusion that was delivered in a speech on "Cyber Security." What are the speaker's weaknesses?
-
4 Lupo Corporation uses a job-order costing system with a single plantwide predetermined overhead rate based on machine-hours. The company based its predetermined overhead rate for the current year...
-
Identify the policing principles and practices (models) of the NSW Police and summarize the differences between another police force in the world. Your answer should focus on the development of their...
-
Locate an HR professional who is willing to be interviewed for about 15 minutes. You can do this by visiting an organization, attending a meeting or conference where there are likely to be HR...
-
Calculate the life insurance gross premium for an insurance company, XYZ Life, under the following assumptions. Please round your answer to the nearest cent. 1-year term insurance for a 30-year-old...
-
In Co-operators General Insurance Company v. Kane, 2017 BCSC 1720, Kane was sued for "unintentional battery assault". Could you help us to understand the meaning of unintentional battery assault?
-
Can you identify, describe, and explain the issue and provide any historical information about diversion programs?
-
Going for a combined DSC TGA analysis is more suitable for studying the thermal stability of materials as compared to using only one of these techniques. Explain why.
-
List four items of financial information you consider to be important to a manager of a business that has been operating for a year.
-
We have seen that gas prices can fluctuate. But during some periods they have moved consistently. Here are the data extracted for one week of each month from January 2002 to May 2007. The bend in the...
-
A national food product company believes that it sells more frozen pizza during the winter months than during the summer months. Average weekly sales for a sample of stores in the Baltimore area over...
-
Occasionally, when I fill my car with gas, I figure out how many miles per gallon my car got. I wrote down those results after six fill-ups in the past few months. Overall, it appears my car gets...
-
What were Aristotles two main classifications of motion?
-
What two main ideas of Aristotle did Galileo discredit?
-
What is the name of the property of objects to maintain their states of motion?
Study smarter with the SolutionInn App