Viscous flow Definition and 20 Threads

Hello everyone 😊, I know that shear stress in turbulent flow is a lot larger from shear stress in laminar flow. My question is about the shear stress at the walls of the pipe. So i was watching a video about shear stress in turbulent flow and the narrator pointed out that the shear stress in...

TL;DR Summary: Analyze, with the help of @Chestermiller, the importance of viscous interactions in a vertical geometry ("Falling ball viscometry") and in an horizontal viscous flow. The following double experiment was conducted by me a few weeks ago. @Chestermiller and I discussed this...

In my first attempt, I started off converting the radii of all three sections from centimeters (10, 8, 6) to meters (0.10 , 0.08 , 0.06), then used the VFR=Av formula to find the speed/velocity of section one. VFR== 0.063 m^3/s A== pi*r^2=pi*(10cm)^2=pi*(0.10)^2=pi*0.01 == 0.031415927 VFR/A=v...

I know how to derive the formula, but I have no idea how to actually use this. Where it says ##50~cm## wide, I'm not sure if that's in the x-direction or the z-direction. ##W##, the width in the equation, is in the z-direction. ##\mu## can be calculated, but I'm not sure what the pressure...

Homework Statement I am revising on the derivation of the differential equation of energy (White's Fluid Mechanics 7th ed) and I'm having trouble understanding the sign convention used in the viscous work term. The textbook first define an elemental control volume and list out the inlet...

Homework Statement Consider the isentropic expansion of air from a fixed given reservoir (i.e. total pressure and temperature). Investigate the behaviour of the value of the Reynolds number of the flow, as a function of the Mach Number M of the expanded flow. For small values of M, the...

Hi I have been reading some internet articles that state the Bernoulli equation does NOT explain the Magnus Effect. The articles state that the effect is due to circulation (Bernoulli requires inviscid flows) Could someone explain the cause of the Magnus effect without reference Bernoulli's...

Does electron gas in metals experience viscosity? Also, does highly charged plasma experience viscosity?

Homework Statement A viscous liquid with density and viscosity ##\rho## and ##\mu## respectively is discharged onto the upper surface of a cylinder with radius ##a## at a volume flow rate ##Q##. This is a gravity-driven flow, and it forms a film around the cylinder--see picture. What is the...

why is it useful to compare viscous flow to inviscid

Homework Statement Water flows at 0.25 L/s through a 9.0-m-long garden hose 2.0 cm in diameter that is lying flat on the ground. The temperature of the water is 20 ∘C. What is the gauge pressure of the water where it enters the hose? Side question: does the velocity of the water flow need to...

Homework Statement A sphere is moving in water at a depth where the absolute pressure is 124kPa. The maximum velocity on a sphere occurs from the forward stagnation point and is 1.5 times the free stream velocity. Calculate the speed of the sphere at which cavitation will occur. Can anyone...

Homework Statement Q.2 One type of bearing that can be used to support very large structures is shown below. Here fluid under pressure is forced from the bearing midpoint (A) to the exterior zone B. thus a pressure distribution occurs as shown. For this bearing which is 30cm wide, what...

Homework Statement Homework Equations ρ=789, μ=.0012 The Attempt at a Solution From the energy equation we get hf=0.9 We know that hf=f(L/D)(V^2)/(2g) [sorry don't know how to use latex after they removed the bar on the right] Now I can substitute V for Q, but I'm stuck with f and Q as...

Hi, I'm trying to solve the flow profile inside an inhomogeneous porous material between two parallel moving plates (essentially Couette flow with a deviation), and I model my system by the following equations: \nabla^2 \mathbf{u} = p(x,y,z) \mathbf{u}\\ \nabla \cdot \mathbf{u} = 0...

Hello, I'm looking at this problem which states: "A parallel air flow along a semi infinite flat plate has undisturbed parameters as follows: " Then they list the speed, temprature, viscousity and pressure. "Demonstrate that the boundary layer can treated by means of incompressible...

Homework Statement What effect does a large positive dCp/dX have on the real viscous flow? This is for an airfoil design project using thin airfoil theory + vortex panel method. The Attempt at a Solution As far as I know Viscosity is independent of pressure, so the only thing I can...

I am doing a project for my aerodynamics class, basically its a simplified version of the thin airfoil theory + vortex paneling method; and I have been asked the following the question: What effect does a large positive dCp/dX (Cp=Pressure Coefficient, x=position) have on the real viscous flow...

viscous flows are always rotational because of shear stress that is exerted on the fluid element due to viscosity. what about the inviscid flows? can they be rotational ? if yes then what are the factors which makes the inviscid flows rotational?

Homework Statement Water (n = 1.00 10-3 Pa·s) is flowing through a horizontal pipe with a volume flow rate of 0.029 m3/s. As the drawing shows, there are two vertical tubes that project from the pipe. From the data in the drawing, find the radius of the horizontal pipe. Homework...