We know that,the shape of electric field line in a cylinder under varying magnetic field is circle,and I wonder,what's the situation if it is a piece of metal with rectangular cross section? I think it might be something like superellipses.Can somebody tell me is it true or how to treat this...
if you have a reference for someone with a semester of thermo (as opposed to a grad student with 3 semesters), a link would be appreciated .
meanwhile, a quick question: temperature, as determined by one of its factors for gases, translational kinetic energy, follows a Planck distribution. but...
Hey guys,
I'm actually working on a project of gravitational vortex turbine at an undergrad level. I need to know the energy or the energy required to make a stable free vortex in a cylinder. The cylinder is of 1 m height and 1.5 m diameter. A channel of 0.5 m width is connected to the...
Hello!
I have some queries regarding Vortex Lattice Method.
I want to design an airfoil using Vortex Lattice Method. For that, I need to find out the equation of airfoil first.
So how exactly am I going to do that?
Please refer the following link...
Hi, I'm a mechatronics student and I am currently working on a project on the effectiveness of a vortex tube to cool a cabinet. The cabinet has a thermostat inside and if the temperature exceeds a threshold, an air compressor is turned on, causing the vortex tube to cool the cabinet. The cabinet...
Dark soliton is a general phynomenon in broad physics subjects. In higher dimensions, dark soliton exhibits instable except one special kind as vortex. The fundamental instability of a single dark soliton in two dimensions is to eventually decay into a number of quantized vortics through what is...
hi,
What is the difference between radial polarization and optical vortex?
thx
http://en.wikipedia.org/wiki/Radial_polarization
http://en.wikipedia.org/wiki/Optical_vortex
http://en.wikipedia.org/wiki/Angular_momentum_of_light
http://en.wikipedia.org/wiki/Orbital_angular_momentum_of_light...
Take a cylinder in cross flow. We know that for Reynolds number greater than 40, we will start to see vortex shedding occur. Using the Strouhal number, we can determine the frequency at which vortices will shed. Using the coefficients of drag and lift, we can determine the steady loadings on...
New photo released today from NASA showing remarkable detail of a hexagon vortex ring at Saturn's North pole.
http://www.space.com/24534-saturn-hexagon-vortex-nasa-cassini-photo.html
Anyone see any papers explaining how the ring gets its shape?
Suppose we have a Type II superconductor that contains a knotted Abrikosov vortex. How long can we expect this to persist? I read that the the core of the vortex is not superconducting, so energy would be dissipated. But how about the supercurrent? Once it got started, what would stop it...
Hi,
In a stirred vessels it can occur that a vortex is present which is unwanted because it decreases the mixing.
The dimensionless Froude number is a value that can be used to see if the vortex formation is negligible or not. It is defined as Fr=N^2D/g an you can look at it as a ratio of...
Homework Statement
The expression below describes a potential vortex in polar coordinates. What is the pressure p in the middle of the vortex, i.e. at radius r=0, relative to the surroundings?
##V_{\theta}=\frac{a}{r}##
Answer:
##p=-∞##
Does anyone have any explanation to this...
I was wondering if we decided that black holes are dense due to the spin and gravity? Are there any other factors for determining density? And could those factors also be true if a black hole were simply a vortex- like a drain per se. A drain that shoots out in two opposite directions, that...
Hi, I would like some help for my final project. I'm trying to find an eqn for fluid resistance which is present on the frontal side of the blade as it spins:
so far what I've come up by dimensional analysis is the drag force equation:
F=Cd x ( ρ x v^2)/2 x A
to get the fluid...
Vortex shedding is mandatory for all the bluff bodies ??
Vortex shedding is mandatory for all the bluff bodies ??
for example, flow over a low thickness flat plate with zero attach angle and flow over the very low depth dish antenna (like U shape)
is there any shape (with particular...
Homework Statement
In a xyz cartesian coordinate system, a thin vortex filament with constant circulation Gamma, forms a square (in the xy plane), with each side of the square having length L. You are told that an infinitesimal segment del (vector) of this filament induces an infinitesimal...
this is written in wiki:
"There are different explanations for the effect and there is debate on which explanation is best or correct.
What is usually agreed upon is that the air in the tube experiences mostly "solid body rotation", which simply means the rotation rate (angular velocity) of...
I noticed something interesting in nature yesterday. I was cleaning a sink that was full to the brim with water and once i was done cleaning my vegetables i pulled the plugged which (of course like we have all witnessed) created a vortex between the top of the waters surface and the drain. Which...
Hi,
I'm looking for an aerodynamic code to model a transonic (say around M=0.8) wing for some basic structural sizing and performance estimation. I'm hoping to use the MATLAB based VLM code Tornado. It has an inbuilt Prandtl-Glauert correction option. I realize that this is technically...
I'm very interested in building this cool device, and was wondering if water could be used instead of air as the injected fluid.
The main differences I notice are the much larger density, and thus possibly smaller angular velocity. And higher viscosity, which could mean a smaller radial...
Hi! I hope I'm posting this in the right forum...
I was wondering if someone could quickly explain what a "vortex surface" is. I've tried to google it, but I only find papers, which won't help me with a simple explanation.
I understand that a vortex surface is an object made from parallel...
Hi everyone,
I am working on a project for the development of a 2D Unsteady Panel Method for Airfoils. As often already suggested in this forum I have been using the book "Low Speed Aerodynamics" which has helped me a lot to produce the Steady State solver (I am writing the code in Matlab at...
If there was any possibility of reversing the direction of wing tip vortices, what would the effects be? Is there any chance of increasing the thrust or lift?
For example the right wing tip produces clockwise vortices and the left wing tip produces counter clockwise vortices(Aircraft viewed...
time for some revision... I can't find any definitive verification for this
I'm trying to find the pressure field of an irrotational vortex, v_theta = 1/r, v_r = 0; I guess the pressure falls but I'm not sure how since the Bernoulli equation constant only holds over streamlines, and over...
I am trying to find a way to eliminate rust in well water. I was wondering if a water vortex could separate the rust from the water. I have a 1" diameter flow at 35 to 50 PSI. Can I place the inlet at the bottom of a larger pipe(I do not what size would be optimum) to create a vortex and have...
Hello,
I'm studying superconductors and I began to wonder about Abrikosov vortices. They possesses a precise quantum flux (h/e), and are also localized in space enough to be exactly pin-pointed by experimental techniques. As it is some kind of a quantum object, shouldn't these vortex properties...
Hello Physics gurus,
lately I watched a nice installation of a dancing light weight fabric.
Over the ground there were placed 8 blowers in circular positioning 45 degrees each one.
So I'm wondering if there was some computer controlling the intensity of all those blowers.
This fabric goes up...
First post here on pf!
I wanted to ask if it's feasible to determine velocities at the top / bottom surface of an airfoil due to the vortex sheet placed on the camber line (due to thin airfoil theory).
I'm attempting to do this because the big picture is to determine the Cp distribution...
Refer page-24 in http://arxiv.org/abs/1010.0443v3
Eq-6.19 is supposed to be the Lagrangian of Abelian-Higgs models. Eg-6.19 is clearly a conserved current of U(1) symmetry. But I can't show how eq-6.21 is a conserved vortex current.
Note: The last term in the Lagrangian is not the usual F_{\mu...
Please Help!
In dealing with wind induced forces, caused by vortex shedding action over a circular cylinder, we must calculate the parameter "Kw" (effective correlation factor), which depends on "L/b", "L" beeing the "correlation lenght" (Eurocode).
Is there any method, analytical (or...
Hi Physics Guys,
I'm not a physics guy myself but some google searching lead me to this site so I signed up so I could ask a question.
I'm into amateur motor sport and I'm currently driving a 1999 Subaru WRX. Anyway I'm always looking out for anything that will increase it's performance...
Alright guys here is the deal, i have had a vortex cooling system on my mind for a while and started wondering
could it be made larger, with more air flowing through it, but with less PSI
and still cool at least somewhat?
i was thinking of making a larger one and attaching it to a high...
Anyone has ever came across this powerplant? I'm a final year mechanical student, and i was asked to design the turbine blade to harness tp obtain the maximum efficiency of the hydro vortex. I'll be glad if someone can help me out by giving me some vortex calculations,simulations or any related...
My initial email to the professor was:
" Either way... what I was wondering about were things related to propulsion. I was thinking about the effect of holding a stick in a steady flowing stream and the back and forth violent rocking like motion. Eventually it got me thinking about something...
Homework Statement
I must determine whether the following vector fields have sources or vortices.
1)\vec A = (\vec x )\frac{\vec a \times \vec x}{r^3} where \vec a is constant and r=||\vec x||.
2)\vec B (\vec x )= \frac{\vec a}{r+ \beta} where \vec a and r are the same as part 1) and \beta >0...
Physics: Vortex air ring shooter?
Using air only & a PUSH or a PULL with a 32 GALLON bin how do i make a vortex ring that
travels Furthest?
- Whats better than a regular plastic trash Bag?
- Use a bungee cord?
- How big does the hole in the 32 Gallon Bin have to be in order to shoot...
Homework Statement
Prior to completing an experiment in which the objective was to analyze control volume energy and entropy in a vortex tube in the Thermal and Fluid Science Laboratory course I am taking, I was required to solve the following two thermodynamics problems:
1. A vortex tube...
Can someone help me with this, I need to prove that a flat vortex sheet of strength \gamma(s) at an angle of attack \alpha with the horizontal and has a p_{2} - p_{1} = \rho V_{\infty} \gamma cos(\alpha)
I just need to mathematically manipulate 2 formulas, namely the following two...
QUESTION 1
Earth's atmosphere is a forced vortex? I guess yes, because an airplane moving to the west does not confront different air resistance than one moving to the east. Correct me if wrong, because I have some doubts: Up to what height? Even the exosphere?
QUESTION 2
Suppose you create...
I was wondering if anyone has any experience with the vortex lattice code Tornado. I would like to modify the source code of Tornado so that it outputs velocity vectors instead of the pressure distribution. I am assuming this is possible because for the vortex lattice method to work the...
The fluid or air speed increases as we are approaching the centre of the vortex. But how much? What's the equation giving the speed f(R) of the fluid at each radius R?
Hello. I am working on a project that requires me to make air move in a vortex. From research, it appears that one of the most common ways of doing this is to rotate a cylindrical screen, which imparts curl to the airflow and thus creates a vortex coaxial and concentric to the center of the...
After a bit of searching of scholarly text and investigations I have found myself unable to find the next piece of information.
Can there exist a vortex ring which travels at supersonic speeds? Not as in the airflow within the vortex ring, there was a paper I was able to acquire about that...
With given object dimensions and speed moving inside a fluid. How do i decide if vortex shedding will occur? It is sometimes obvious just to look at the speed and dimension and say it will not occur as its going too slow or vice versa. Is there formula or some mathematical criterion to...