Fluid Definition and 1000 Threads

Homework Statement Task number 2. The problem is that my solution is wrong but the lecturer didnt want to explain what is wrong, she insists on doing it by myself. But to be honest I'm not really good at it and I just need someone either explain it or solve or at least check it and tell me...

Homework Statement In 1993 the radius of Hurricane Emily was about 350 km. The wind speed near the center ("eye") of the hurricane, whose radius was about 30 km, reached about 200 km/h. As air swirled in from the rim of the hurricane toward the eye, its angular momentum remained roughly...

Homework Statement The problem depicts a tube shaped like a "U". The arms of the tube are 0.3m in height and the horizontal part of the tube is 0.6m long. The left arm of the tube is open while the right arm of the tube is closed. The problem states that the liquid in the tube is of density...

I have two reservoirs, connected by two pipes. The first reservoir is higher in elevation than the second. If the system is full of static water, what would the total energy line look like? Since the velocity of the flow through the system is 0, would the total energy line just be a straight...

Hello, I have two fish tanks next to each other. One is big (36 gallons, about 2 feet tall), one is smaller (10 gallons, about a foot tall). I want to make a connective tube so that my eel can swim between the two tanks but I don't want either tank to overflow. I am not adverse to raising the...

I was just wondering why a body immersed in a fluid at rest experiences a perpendicular force on its surface? Why can't there be a component of force in parallel direction to the surface ? I read somewhere that this would cause the fluid to flow parallel to the surface but i don't quite...

Homework Statement For a flow of a compressible fluid through a narrow tube, the following statement is correct a) the volume of the fluid crossing any section of the tube is constant. b) density of the fluid is independent of pressure. c) mass of the fluid crossing any section of the...

Homework Statement Water stands at a depth D behind the vertical upstream face of a dam. Let W be the width of the dam. Find the resultant horizontal force exerted on the dam by the water. The Attempt at a Solution So I know how to solve the problem, I was just unsure of whether we...

While working on fluid dynamics problems I noticed that the incline angle sometimes starts at middle while other times starts at one end. Is there an explanation for this? I know the slope =(linear a)/(gravitational g)

Homework Statement What is wrong with the following argument from Bernoulli's equation? Suppose a fluid in a bucket is rotating under gravity with constant angular velocity W so that velocity is: u = (-\Omega y,\Omega x, 0). Then: \frac{P}{\rho} + \frac{u^2}{2} + gz = constant...

Hi, I was wondering if anyone would be able to help me with this problem:Homework Statement I have a mass, that is being held in the air by several downwards pointing jets of water. I know the diameter of the nozzles from which the jets are flowing, and the flow (Q) from each jet, which is the...

Most liquids can be assumed to be incompressible, since the Mach-number is much smaller than 1. That means that the density variations are negligible and from the relation between pressure p and density ρ, p=c_s^2 \rho we see that the pressure in constant as well. Now, say that I look at a...

Hi Guys. I hope some of you are able to help me out. This is NOT a homework. I have to explain the difference between the three different rate of change (time derivatives) of a property (such as mass, momentum, internal energy, etc) in a continuum? 1 )The partial time derivative 2)...

Homework Statement I have some conceptual question in the fluid mechanics topics which has been bugging me for quite some time now. 1) When wax is rubbed on cloth why does the cloth become waterproof 2) A weightless baloon is filled with water. What will be the apparent weight when...

Hi The speed of sound in a fluid is defined as c_s^2 = \frac{\partial P}{\partial \rho} where P is the pressure and ρ the density. In my thermodynamics-course this was how we defined the speed of sound in an ideal gas, I have never read the explanation anywhere for, why this relation is also...

Homework Statement what factors affect the size of the pressure at a point in a static fluid? Homework Equations The Attempt at a Solution

why the forces in pressure always taken perpendicular? and if they are taken then to which direction? and what about presure on a curved plane?

Hi When we talk about a fluid moving at low Mach numbers, it is said to be incompressible. But does this mean that the flow is incompressible (i.e., material derivate is zero) or does it imply that the fluid itself is incompressible (constant density)? If anybody has a reference (book...

Homework Statement Good evening. First post on this forum! The problem I wish to state would take too long to write by hand so I thought it best to do so via attachment. The question I am stuck on is part d and, in fact, part e also. Homework Equations All relevant equations are given...

Hi! When you are calculating ##\psi## or ##\phi## from the horizontal or vertical velocity components of a fluid's velocity, you end up with a constant ##C## carried along with the function. In my class, the professor just said something about them being arbitrary (I think..) and set them to...

1. Hi All I had a quiz in my fluid mechanics class with the question A ship model scale 1/25 is towed through seawater at a speed of 1m/s. A force of 2N is required to tow the model. Find the speed of the ship if the prototype is subjected to wave resistance only. 2. REm=REp...

Homework Statement We recently did an experiment involving the impact of fluid jet on both plane and cupped surfaces. See the diagram attached for the experimental set up. We were asked to 1) verify the conservation of momentum and 2) calculate the discharge coefficient of the nozzle from...

I have two cylindrical tubes connected at a 90 degree junction. One tube has a constant flow of a laminar fluid going through it and the fluid is saturated by a soluble particulate with a known concentration. The other tube has a much smaller radius, initially has no particles and is closed at...

Homework Statement The two-dimensional steady flow of a fluid with density ρ is given by v=K(-yex + xey) / (x2 + y2) where K is a constant (a) Can this flow corespond to the flow of anincompressible fluid? (b) Determine and sketch the streamlines of this flow. (c) Determine and sketch...

Homework Statement An incompressible fluid with density ρ is in a horizontal test tube of inner cross-sectional area A. The test tube spins in a horizontal circle in an ultracentrifuge at an angular speed ω. Gravitational forces are negligible. Consider a volume element of the fluid of area...

Determine velocity of a fluid -- not enough info given? Hi folks, I'm currently in an internship at Cassidian, and my supervisor has asked me to calculate the velocity of a fluid. I didn't spend too long on the subject, maybe an hour or two, but I wasn't particularly busy that day. I...

Hey all. I am an undergraduate math major in my third year who is planning to do a reading course in fluid mechanics next term. I have taken courses in rigorous advanced calculus, real and complex analysis, topology, and intro ODE and PDE. I would be taking a differential geometry course, which...

Homework Statement A hydraulic car lift has a reservoir of fluid connected to two cylindrical fluid filled pipes. The pipe directly below the car has a diameter of 1.8 m. the pipe o which the plunger acts has a diameter of 0.045m. the plunger is depressed a distance of 1.5m. How much does the...

Fluid Mechanics Question! Help needed :( Homework Statement It has been proposed that we could explore Mars with inflatable balloons. the density of the Martian atmosphere is 0.0154kg/m^3 (ignore that this varies with temperature). Suppose we make the balloons out of a thin tough plastic...

For the problem attached, I solved it and found the answer for part b : 80.21 s How to get sure or know if the answer is right or not. Thanks

Homework Statement Water travels through a pipe with a radius of 1 inch at a speed of 2 m/s. There is a nozzle at the end of the pipe with a radius of 1/4 inch. The pipe is horizontal and 2m above the ground. How far does the water travel in the air before hitting the ground? r1 = 1 in. r2...

How to find the dancy friction factor by using the colebrook white equation (not using the moody chart) ; to calculate the 1/√f = -2LOG[(e/d)/3.71 + 2.51/(Re*√f)] help please

Homework Statement A horizontally oriented tube AB of length ##l## rotate with a constant angular velocity ##\omega## about a stationary axis OO' passing through the end A. The tube is filled with an ideal fluid. The end A of the tube is open, the closed end B has a very small orifice. Find the...

Homework Statement A sphere of radius ##a## is submerged in a fluid which is flowing in the z-hat direction. There is some associated viscosity in the fluid which will exert a force on the sphere. Use symmetry to argue that the net force will be in the z-direction. Show that it will have the...

Homework Statement The horizontal bottom of a wide vessel with an ideal fluid has a round orifice of radius ##R_1## over which a round closed cylinder is mounted, whose radius ##R_2>R_1##. The clearance between the cylinder and the bottom of vessel is very small, the fluid density is ##\rho##...

I trying to come up with a way to measure the power output of an engine using a water pump, And I wanted some one to go over my math and check for flaws in my thoughts. My idea is to measure the flow rate and the pressure of the output of the water pump. Using this math to solve for power...

Hi guys, I studied mechanical engineering and I am currently a graduate student (turbulence modeling). I am interested in the more formal/mathematical aspects of fluid dynamics, which are mainly worked in mathematical faculties and I would like to know if someone knows/have an idea about...

hey pf! i am studying fluid mechanics and was wondering if any of you are familiar with a flow around some geometry? for example, perhaps a 2-D fluid flowing around a circle? if so please reply, as i am wondering how to model the navier-stokes equations. i'll be happy to post the equations...

Hello, I would just like some clarification on this... When you calculate "total" pressure at a depth in a fluid do you have to add on the value for atmospheric pressure?? Thanks, Molly :-)

hey pf! i am studying fluid mechanics and we are reviewing navier/stokes equations. we have gone over a few problems, but i could definitely use practice on more. do you all have any suggestions that include solutions, not just answers, so if I am stuck i can see how to solve? problems...

Homework Statement A block of mass 20 g sits at rest on a plate that is at the top of the fluid on one side of a U-tube as shown below. The U-tube contains two different fluids with densities ρ1 = 1070 kg/m3 and ρ2 = 650 kg/m3 and has a cross sectional area A = 4.6 * 10-4 m2. The surfaces...

Homework Statement The aerodynamic drag of a new sports car is to be predicted at a speed of 100 km/hr at air temperature of 25°C. Automotive engineers build a ¼ scale model of the car to test in a wind tunnel, where the air temperature is 10°C. A drag balance is used to measure the drag...

I understand that as an incompressible fluid flows through a pipe with decreasing cross sectional area the velocity increases. This must happen for the mass/volume continuity equations to be true. Since the velocity is increasing though there has to be a net pressure on the fluid right? My...

Homework Statement The block of ice (temperature 0°C) shown in Figure P9.57 is drawn over a level surface lubricated by a layer of water 0.10 mm thick. Determine the magnitude of the force needed to pull the block with a constant speed of 0.50 m/s. At 0°C, the viscosity of water has the...

Homework Statement see the pic attached Homework Equations Newton's law of viscosity The Attempt at a Solution okay, i knew that , since the viscosity of the fuid in the second tube is low, it flows easily than the other, but i don't know which exact euation connects visocsity...

Homework Statement A uniform wooden stick of density d is completely immersed in water of density D (D>d). One end of the stick is free to rotate about a hinge which is attached to the wall of the container. In equilibrium the stick the stick makes an angle θ then tanθ is- (a)0 (b)d/D...

Homework Statement Water is flowing into and discharging from a U-shaped pipe section as shown. At flange (1), 30 kg/s of water flows into the section with the total absolute pressure of 200 kPa. At flange (2), the absolute pressure is 150 kPa. At location (3), 8 kg/s of water discharges...

I am thinking that... if a tank of water which contains a small wooden block is kept in an elevator which is accelerating upwards from rest, will the block get more dipped or remains constant position with respect to water??

Resistance -- fluid resistance to ball motion A ball of mass m = 3 kg is falling from an initial height y = 3 m in an area where the acceleration due to gravity can be approximated as g = 10 m/s2. As it falls the ball is subjected to a fluid resistance of magnitude FR = kv where k = 6 kg/s. How...

Can anyone recommend me a book on Fluid Mechanics? I've been recommended Landau's book on Fluid Mechanics, but I haven't learned Statistical Mechanics which is required in his book.