By using order of magnitude analysis, the continuity and Navier–Stokes equations can be simplified to the Prandtl boundarylayer equations. For steady, incompressible, and two-dimensional flow, neglecting gravity, the result is
Use L and V0 as characteristic length and velocity, respectively. Nondimensionalize these equations and identify the similarity parameters that result.
Want to see the full answer?
Check out a sample textbook solutionChapter 7 Solutions
Fox And Mcdonald's Introduction To Fluid Mechanics
Additional Engineering Textbook Solutions
Thinking Like an Engineer: An Active Learning Approach (4th Edition)
Degarmo's Materials And Processes In Manufacturing
Fluid Mechanics: Fundamentals and Applications
Starting Out with Java: From Control Structures through Objects (7th Edition) (What's New in Computer Science)
Computer Science: An Overview (13th Edition) (What's New in Computer Science)
Starting Out with Python (4th Edition)
- I am confused whether points A and B do not lie on the same streamline in this equation.arrow_forwardA simple parallel flow with constant velocity shear σ is given byu = σy v = w = 0 Evaluate the five components of motion (e.g. translation, divergence, vorticity,shearing and stretching deformation.)arrow_forwardK1arrow_forward
- An incompressible fluid of density ρ and viscosity μ flows down a plane inclined at an angle α.Assume constant gravitational acceleration downward, fully-developed flow, constant pressure inthe air outside the fluid, and zero stress exerted by the air on the fluid. i) Starting from the incompressible Navier-Stokes equations, derive the differential equation andboundary conditions that govern the velocity u(y). ii) Solve the equation from the previous part for u(y). iii) Using your solution, calculate the following quantities: The mass flow rate (per unit depth) down the channel. The vorticity vector, ~ξ, and rate-of-strain tensor, epsilon at a point (x, y) in the channel. The shear stress exerted by the fluid on the bottom wall The viscous force in the fluid iv) Consider a control volume consisting of a section of length L of the channel. Demonstratethat the conservation of x momentum holds for this control volume by integrating appropriatequantities over its perimeter and…arrow_forwardTwo different flow fields over two different bodies are dynamically similar if (a) The streamline patterns are geometrically similar; TRUE OR FALSE (b) The non-dimensional distributions such as V/V∞, p/p∞, etc, are the same when plotted against common non-dimensional coordinates TRUE or FALSE? (c) Force coefficients are the same TRUE or FALSE? (d) State the criteria for two flows to be dynamically similar (e) An airplane flies at 800km/h at 11700m standard altitude where the ambient pressure and temperature are 20.335 kPA and 216.66K respectively. A 1/50 scale model of the airplane is tested in a wind tunnel where the temperature is 288K. Calculate the tunnel test section wind speed and pressure such that force coefficients of the model and prototype are the same. Assume viscosity is proportional to the square root of T. [ Hint: flow is viscous and compressible; equation of state for a perfect gas applies]arrow_forwardWrite a one-word description of each of the five terms in the incompressible Navier–Stokes equation, When the creeping flow approximation is made, only two of the five terms remain. Which two terms remain, and why is this significant?arrow_forward
- An incompressible velocity field is given by u=a(x°y²-y), v unknown, w=bxyz where a and b are constants. (a)What is the form of the velocity component for that the flow conserves mass? (b) Write Navier- Stokes's equation in 2-dimensional space with x-y coordinate system.arrow_forwardAn equation for the velocity for a 2D planar converging nozzle is Uy u =U1+ w=0 L Where U is the speed of the flow entering into the nozzle, and L is the length. Determine if these satisfy the continuity equation. Write the Navier-Stokes equations in x and y directions, simplify them appropriately, and integrate to determine the pressure distribution P(x.y) in the nozzle. Assume that at x = 0, y = 0, the pressure is a known value, P.arrow_forwardb) Derive the Navier-Stokes of continuity Equation If the fluid is incompressible, p = constant, independent of space and time, so that dp/ờt = 0. The continuity equation then reduces to v-v = 0.arrow_forward
- Question A2 Consider a steady two-dimensional steady viscous incompressible flow between two infinitely large parallel plates (Figure QA2). Assume the top plate is moving to the right at a constant speed U₁. +h -h YA U1 1 Top Plate (1+ X dp a) If the pressure gradient in the direction of flow is h² Fluid (P.) Bottom Plate dp h Uιμ dx Figure QA2 conservation equations and show that the velocity distribution between the two plate can be expressed as: -2) dx 2h By making reasonal assumptions, solve the b) Assume U₁ =10m/s, h=200 mm, μ = 1.0x 10-3³ Ns/m², dP dx the wall shear stress at y = th. U₁ What is the power requirement to drag the top plate at this speed? = 0.50 N/m² m Calculate (d) Do you expect to have a flow reversal in any part of the flow? If yes, would it occur close to the top plate or bottom plate? Explain.arrow_forwardOne of the conditions in using the Bernoulli equation is the requirement of inviscid flow. However there is no fluid with zero viscosity in the world except some peculiar fluid at very low temperature. Bernoulli equation or inviscid flow theory is still a very important branch of fluid dynamics for the following reasons: (i) (ii) There is wide region of flow where the velocity gradient is zero and so the viscous effect does not manifest itself, such as in external flow past an un- stalled aerofoil. The conservation of useful energy allows the conversion of kinetic and potential energy to pressure and hence pressure force acting normal to the control volume or system boundary even though the tangential friction stress is absent. It allows the estimation of losses in internal pipe flow. (A) (i) and (ii) (B) (i) and (iii) (ii) and (iii) All of the above (C) (D)arrow_forwardBy using the Navier-Stokes equation for a flow of a Newtonian viscous fluid in a rectangular channel, find the governing PDE for velocity distribution in the figure below. Illustrate the utilized mathematical variable change approach that is necessary for solving this Poisson partial differential equation. Then determine the velocity profile in y direction. y 2h N 21arrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY