Fluid dynamics Definition and 608 Threads

Hi, I've decided I want to pursue a career in CFD (Computational Fluid Dynamics) and I think the best career option for me would be be to take up 'teaching' in my area of interest (since I'm not sure how well I'd be able to do in hard-core research activities) . However, I'm completely unaware...

Homework Statement A circular jet of water of radius r1 is propelled vertically downwards and hits a circular plate of radius r2 (> r1 ) so that the centre of the jet is incident onto the centre of the plate. The velocity of the jet as it hits the plate is v and is normal to the plate...

Dear all I have 1 simple question. If the solution of Navier Stokes equation exists, its limits for infimum length, time and velocity would be the Kolmogorov Microscale equations, am I correct? Thanks, Robert

Suppose an inviscid, incompressible fluid is rotating uniformly with angular velocity \Omega. Take Cartesian axes fixed in a frame rotating with that angular velocity. Show that the evolution of a SMALL velocity field, u_1 = (u_1, v_1, w_1), relative to the rotating axes and starting from rest...

Homework Statement Consider a water pipe that tapers down from a diameter d_A = 5.0 cm at end A to a diameter d_B = 2.5 cm at end B. At each end a vertical pipe that is open to the air at the top is attached to the pipe. Assume that water flows through the pipe at high enough pressure that the...

Homework Statement Show that, for an inviscid fluid, we have \frac{D}{Dt}\bigg{(}\frac{\mathbf{\omega}}{\rho}\bigg{)} = \bigg{(}\frac{\mathbf{\omega}}{\rho}\cdot \nabla \bigg{)}\mathbf{u} - \frac{1}{\rho}\nabla\bigg{(}\frac{1}{\rho}\bigg{)} \times \nabla p Homework Equations Euler's...

Homework Statement An ideal fluid is rotating under gravity g with constant angular velocicy \Omega, so that relative to the fixed Cartesian axes \mathbf{u} = (-\Omega y, \Omega x, 0). We wish to find the surfaces of constant pressure, and hence the surface of a uniformly rotating bucket of...

I am finding the recommended textbook for fluid dynamics really dull. It's slowly going from one formula to another with nothing interesting or any attempt at all to keep you awake... I'm strong with regard to maths, so are there any books that might make the subject more interesting? Even...

Problem Statement A 50cm by 30cm by 20cm block weighing 150N is to be moved at a constant velocity of .8 m/s on an inclined surface with a friction coefficient of 0.27. (a) Determine the force f that needs to be applied in the horizontal direction. (b) if a .4mm thick oil film with a dynamic...

Homework Statement A very large open water tank has a 50 cm diameter output pipe connected 10 m above the water main which is 6 cm in diameter. If the gauge pressure in the water main reads 9.8 E4 Pa what is the speed at whic the water is supplied? Homework Equations Bernoulli's...

If this isn't the right forum, please move me to a better one. Assume that the output of a mountain spring is diverted to a reservoir about 200 feet below the spring through the following airtight system: A two inch pipe leads from the spring to a 40-gallon drum that lies on its side a few...

So basically I'm considering applying to physics or applied physics grad programs. But I'm also considering doing CFD as a career. I was hoping there was a way I could see them both in a grad program, but I haven't seen any physics grad programs with CFD as a research area by itself. Rather, I...

Fluid Dynamics - Multiple Pipe System Need Help Please! There are 2 pumps at 2 locations with pipes (12") running from each of the pumps that are to both tied into 1 pipe (16"). In order to tie the 2 pipes into the one pipe there will be a 90 and a y fitting. The 16" pipe will then continue...

Homework Statement An iceberg is floating on sea water such that only 10% of its volume is above the water level. What is the density of sea water expressed in terms of the density of ice. Homework Equations \frac{Vf}{Vi} = \frac{\rho}{\rho} \rhof = density of sea water \rhoi =...

Hello Physics Forums, I am going into 2nd year physics and am thinking about taking some additional math courses. My interests lay with ships and the ocean. What math courses would be most useful for research in fluid dynamics and interactions with structures? Thanks, Adam

Q) " Estimate the average acceleration of water as it travels through the nozzle on your garden hose. List all the assumptions and show calculations. " Plz help...ny body before i come a dead body ! :mad:

Homework Statement A fire-hose must be able to shoot water to the top of a building 35.0 m tall when aimed straight up. Water enters this hose at a steady rate of 0.500 m³.s¯¹ and shoots out of a round nozzle. (a) What is the maximum diameter that this nozzle can have? (4 marks) (b)...

I'm no good with fluid dynamics. I really am willing to improve can someone point me to what equation I should use for this question. I assume its bernoullis equation? I've drawn a diagram of how I see the pipe. To make things worse I haven't done fluids in quite a while. Homework...

i want to master computational fluid dynamics,i do not have that as a subject in my university.so if i do it on my own,please give an idea about the best books for it?

Let's say I want to install a 55 gallon drum on the ground to collect rain water as it runs off the roof. What if for some strange reason I wanted to run a hose from a spigot in the bottom of the drum back up to water the plants on the roof deck (I'm looking into green roofs). Could we just...

1.Water flows in a horizontal pipe with variable radius and which produces no drag. At one point in the pipe where the radius is 5.0cm, the flow is noted as .75 m/s at a pressure of 250 N/m^2. a) What is the velocity at a point in the pipe where the pressure is 200 N/m^2? b) What is the radius...

Sorry I'm not sure where to post this as there is no explicit fluid dynamics forum - i just did a search and noticed majority of posts fell into the "mechanical engineering" forum for some reason. Sorry about that. Today my professor has told the class that by next week we have to code in...

Hi everyone, I am new to the forum, so please instruct me if I commit any posting faux pas in my first post. Here is my dilemma: I have an oxygen concentrator that outputs .5-5 liters per minute of 95% concentrated oxygen at 5 - 7 PSI. This is just fine for medical use, but I am trying to...

Homework Statement A hypodermic syringe contains a medicine with the density of water. The barrel of the syringe has a cross-sectional area of 2.5*10^-5 m^2. In the absense of a force on the plunger, making the medicine squirt from the needle. If the syringe is horizontal and the pressure...

I am having a tank at the bottom of which a pump suction line is connected.. there is another parralel line to that bottom line which is coming from another tank and open to atmospheric pressure. Please note that this second pipe is connected to the bottom pipe; not to the first tank...

(a) Is it true that if the mass flow rate of a gas is low, say 2g/s (grams per second), the friction losses and other losses in the piping will be negligible? (b) If it is true that losses in the piping are negligible, is it the Euler's dimensionless number that we can use to prove this...

Homework Statement okay, so the lab that we did is called fluid dynamics. where we open a hole but before we are supposed to record h1 before the hole is open and also measure the height of the hole. h1 is higher than h. so every 30 seconds, we have to record h2, h3 ,h4 corresonding with...

Homework Statement The horizontal constricted pipe illustrated in lee (vl3765) – UTHW#34-Dluid Dynamics1 – hamaguchi – (32001) 3 the figure (a Venturi tube), can be used to measure flow velocities in an incompressible fluid. The ratio for the cross section areas of the tube is A2/A1 =...

just wanted to say hi first as this is my first post. I will explain the story... There is an ongowing debate within the Kitesurfing world regarding the aerodynamics of LEI (leading edge inflateable) kites and Foil (like RAM aim parachutes) kites. LEI Kites: They have large inflateable...

Can fluid dynamics be applied to a particle moving through a Higgs field? Like is there a wake, or even a slipstream in which a trailing particle might be affected less by the Higgs field or not at all?

How much force is necessary to lift a ring, diameter 20mm, made of fine wire, and placed on the surface of water at 20 degrees celsius? All the equations from the chapter: Shearing stress = F/A = Viscosity*(velocity parallel/h) Kinematic Viscosity = viscosity/density Change in pressure =...

"If you put your arm in a stream flowing at U metres per second, how far can water rise up it?" Not really sure if what I'm doing is right. Presumably it depends on the angle of your arm in the water. If we let the speed of the water at your arm be V, we get, by Bernoulli, taking the height...

http://home.cc.umanitoba.ca/~loly/102-dec_word.pdf The above is a link to the problem - Question #3. Homework Statement A glass tube has several different cross-sectional areas with the values indicated in the figure. A piston at the left end of the tube exerts pressure so that the mercury...

Before I describe the problem, I would like to apologize for my lack of comprehension of this subject. It is the first semester of Physics, but the end, and has become quite complicated. Homework Statement There is a 2.0 L soda bottle used, with a hole a certain height (hhole) from the...

Homework Statement Consider the Rayleigh problem, but allow the plate velocity to be a function of time, V(t). By differentiation show that the shear stress, tau = du/dy*absolute viscosity, obeys the same diffusion equation that the velocity does. Suppose that the plate is moved in such a way...

Hey guys, I have the following (non-homework) problem: I am simulating a collection of normally distributed non-interacting stars falling into a much larger galactic potential from some radial distance and some initial velocity and watching them slosh around in this potential. Currently i...

We have a combination of two very long coaxial tubes with radii R and 2R. The tubes are placed vertically, the space between the tubes is filled with a heavy fluid of viscosity. The outer tube glides stationary down under the action of gravity, the inner tube is at rest. Both tube ends are open...

Heya , sorry but could someone check what I've done is right ? The remainder of the question relies on these answers :S Homework Statement We consider a homogeneous fluid in a sphere of radius r0 = 1 in the limit of kinematic viscosity v = 0 which is rotating uniformly about its axis...

Homework Statement The spout heights for a container are 10 cm, 20cm, 30cm, and 40cm. The water level is maintained at a 45 cm height by an outside supply. Which water steam has the greatest range relative to the base of the container. --- I know that the one at 20cm is the greatest range...

Homework Statement Water is flowing through a pipe of radius 4 cm with a speed of 15 m/s The pipe increases 3 M in height with no change in pressure or speed. What is the radius of the pipe in cm at this new height?Homework Equations P1+1/2\rhoV12+\rhogY1=P2+1/2\rhoV22+\rhogY2 The rho's are not...

Homework Statement Water flowing out of a 15.0mm -diameter faucet fills a 1.50 L bottle in 5.00s. At what distance below the faucet has the water stream narrowed to 10 mm in diameter? Homework Equations Bernoulli's equation: P_1+pgh+1/2pv^2=constant Q(volume flow rate)=vA Continuity...

Hi everyone, I hope you can help me out with this question as my exam is tomorow. Homework Statement A 355 mL soda can with diameter=6.2 cm has a mass of 20g. If it is half full with water, and it is floating upright on water, what length of the can is abover the water level...

Imagine a jet of fluid (perhaps air) impinging on a flat plate. It could be said that the jet has a slightly higher mean velocity in the direction normal to the flat surface (we'll arbitrarily call this X). From a classical thermodynamic point of view it could be said that the gas has a higher...

could anybody suggest me a book on fluid mechanics which provide strong basics as well as detailed knowledge thanks

Homework Statement A container has spouts 10 cm, 20 cm, 30 cm, and 40 cm. The water level is maintained at a 45 cm height by an outside supply. (a) what is the speed of the water out of each hole? (b) which water stream has the greatest range relative to the base of the container...

Homework Statement How many cubic metres of helium are required to lift a balloon with a 400 kg payload to 8000 m? Assume balloon maintains constant volume, and density of the air decreases with altitude z according to the expression \rhoair = \rho^e^-z/8000, where z is in metres and po =...

[b]1. Verify that vj∂jvi=∂i(1/2*v2)-εijkvjωk,where ωk=εklm∂lvm Homework Equations The Attempt at a Solution I am confused on how to proceed with this problem up to this point I have decomposed ωk into Curl(v). Which leaves vj X Curl(v). Decomposing this leaves vm∇ivm-vl∇lvi. I am...

Through a pipe 15.0cm in diameter, water is pumped from the Colorado River up to Grand Canyon Village, located on the rim of the canyon. The river is at an elevation of 564m, and the village is at an elevation of 2096m (a) What is the minimum pressure at which the water must be pumped if it is...

Hello all, I'm interested in studying fluid dynamics as a profession but I'm uncertain as to what course of study I should pursue as an undergraduate. I've been thinking about taking my BA in mathematics and physics but due to the seemingly heavy computational nature of much of the work being...

Heh...this question actually looks as simple as hell (and it probably is)...but there always seems to be one variable missing: A large storage tank, open at the top and filled with water, develops a small hole in its side at a point 16.0m below the water level. if the rate of flow from the...