Flow Definition and 1000 Threads

I tried posting this question in this forum a couple of weeks ago, but didn't get an answer to my question. I'm going to try posting it again using the formatting template so that it is hopefully clearer. I am also not sure if this is the right forum to be posting this in. It is a problem I ran...

Are fluid streamlines in an irrotational, but viscous, flow parallel? Or does the flow need to be both irrotational and inviscid?

Hi, A chamber (manifold type cylinder) has 1 inlet and 8 outlets of 3 inch diameter each. 8 suction blowers are connected to the chamber's outlet. Each blower's suction flow rate is 1000 cfm. what will be the flow rate through the inlet of the chamber (diameter = 3 inches). Will the inlet...

If throttling reduces mass flow rate then how can we say it as steady flow process where the mass flow rate is constant?

Homework Statement At a processing plant, olive oil of density 875 kg/m3 flows in a horizontal section of hose that constricts from a diameter of 2.92 cm to a diameter of 1.20 cm. Assume steady, ideal flow. What is the volume flow rate if the change in pressure between the two sections of hose...

Homework Statement [/B] Find an equation for the flow velocity of a river that is parallel to the bottom as a function of the perpendicular distance from the surface. Apply the boundary conditions given and solve, and find the velocity at the surface. Note that the coordinates are: x is the...

I'm about to attempt this question but beforehand I was hoping if someone could just check if my diagram is correct on the basis of the question; A feed stream contains H2, CO and a trace of CH4. Pure CH3OH is produced by means of a reactor (CO + 2H2→CH3OH), separator and recycle with purge to...

So you can solve the Stokes equation for flow around a sphere to obtain the pressure in the fluid: p=p0-3nuacosθ/2r2 where n is the viscosity, u is the speed of the fluid (along the z axis) far away from the sphere, a is the radius of the sphere and r,θ are the usual spherical polar coordinates...

Angular momentum is conserved in a closed system. Is thermal isolation required too? An example special case in mind is a closed cavity high speed rotation. It contains high pressure gas and the thermal flow is driving convection currents creating turbulence and or a heat pumping loop...

Homework Statement Fluid flows between 2 parallel plates, flow is fully developed and laminar, the distance between the plates is h In the notes there is a general form of solution after integrating it 2 times. where a is h. but i saw in the book that we have to get +h/2 and -h/2 then add...

If we have a source of AC current with two terminals ( A and B ). We connect a device with this source. Now we say that one wire is live and other is neutral. But my question is that, how one wire is neutral. As we say that in AC current the terminals change the polarity. Its mean that some...

I am an electrical guy, i can't understand the concept of constant flow system...and how temperature is controlled in room by Air conditioner...thanks

In the full internal reflection case where we have a refracted evanescent wave, If another object is nearby, then we could have wave tunneling phenomenon(frustrated total internal reflection). 1) So, how can the evanescent wave which does not transfer any net energy produce another wave at the...

A building has a water pipe inlet. I have found that at if I open the valve at this location fully, then I get 180 liters per minute at a residual pressure of 0,2 bars (static pressure is 5,4 bars). Is there a fixed relationship between the flow and pressure drop so that I can easily predict...

Hi All, I'm hoping to work on deriving the governing fluid flow equations for a frisbee in flight theoretically and then to test it on a wind tunnel, and compare results. If u could please help on how do i apply/derive the necessary equations. Respectful Regards

Homework Statement (This isn't homework; someone is insisting that the graph of height of a leaking water column/time is a parabola, which makes no logical sense to me, but I want to prove it) You have a bucket (5 gal) filled to the top with water, and a small hole in the bottom. Find the...

Hi, I'm building an experimental set-up for some heat exchanger I'm trying to analyze, I want to maximize the flow through this little piece. I have a stable temperature bath, (see picture) that has an evacuation valve on the bottom. I only took introduction to Fluid Dynamics (found it amazing...

I am going to presenting on a scientific report and the report that I choose (this can still change) is the following: http://onlinelibrary.wiley.com/doi/10.1029/2001GL013014/pdf In this report, they ask the question of what produces what? Does plasma flow produce an electric field? or Does an...

Can someone explain why after a certain voltage, current flows. We were taught that in pn junction when a reverse voltage is applied the depletion region grows wider. Using this no matter what the voltage current should not increase. So why does a current flow when a reverse current is applied.

Homework Statement Hello everyone, I am having a problem whether or not a turbulence at a specific location (let's say A) is isotropic or not. I have calculated the two root mean square values of velocity fluctuations measured at the point A in a fully developed turbulent pipe flow. the first...

Hello everybody, I have a computer case project and I need to create a fanless (passive) cooling. I feel excited of the idea to use paltier thermoelectric coolers, but their efficiency is considered very low, because the hot side is usually exhausted via passive radiators. So I came up with...

I'm looking at an ungounded 3-phase system here for starters. In a perfectly ungrounded system, grabbing a phase seems safe in theory, but in practice (because perfect ungrounded doesn't exist), this is a bad idea. I'm trying to determine exactly WHY. If I have a perfect ungrounded system...

I am currently designing a lubrication system which uses a positive displacement gear pump. So how can I get the flow rate of a lubrication system? i don't know which equation to use. thank you so much.

Sodium ion flows a through a cylindrical ion channel --> diameter = 0.85 um and is 5 um long. potential difference b/w the ends of the channel is 225 mV drift velocity = 0.015 m/s in a period of 1 ms, a total of 15*10^6 ions exit the channel a. total charge exiting the channel in 1 ms =? b...

Hello everyone, i am currently dimensioning a compression system using a vehicle turbocharger and need to find a way to relate the pressure ratio of the compressor and the mass flow rate. (flows trough compressor and turbine are of course separated) For the turbine, one can use Stodola's...

QUESTION: In general: when a flow is considered steady does that mean all properties of the flow are steady? Or: can a flow have steady and unsteady properties?

You have a capillary with a stream of water vapor flowing through. Inside the capillary argon gas is also flowing (in the same direction) with a flow rate of 3 L/min. How high of a flow rate can the water vapor have before it starts condensing on the walls? Flow is laminar and the system is at...

I am looking for some advice on the experiment described below. I am attempting to use electric potential to move negatively charged RNA toward a positive electrode. The procedure is similar to traditional electrophoresis except there is no gel or dies. I attempt to describe the setup below...

Hello, I have to calculate the air flow through a small rectangular opening with following data: - temperature at one side: 1200°C - temperature at other side: 20°C - pressure at hotter side is 3 mm WC lower than the colder side - the length of the opening is 240 mm - the width of the opening is...

In short circuit it is said that there is no resistance. So the current produce heat and wire is burnt. But as the rise in temperature increase the resistance then in short circuit heat must rise the resistance. How can we say there is no resistance in short circuit?

Homework Statement Homework Equations [/B] When a diode is reverse biased positive donor ions are left in the N semiconductor and negative acceptor ions in the P type. And since the N is conected to + and its donnor ions has a large +charge, why no electrons from P cannot cross the junction and...

Homework Statement I have been given a question which I can't seem to get my head around fully for one reason. I keep finding myself stuck with 2 unknown variables. Here is the information given.. V (terminal velocity) = Unknown g (gravity acc.) = 9.81m/s2 d (diameter of particle) = ? Pp =...

So I'm trying to make a Hot-Water Rocket. But I want to make the necessary thermodynamics calculations first. What kind of flow will it be in such systems I think it's obviously going to be an unsteady flow but is it uniform or not? I also would love if you guys linked me to unsteady...

Hey! I am currently working on modeling and solving a scenario with oil and water flow. The flow is supposed to be driven purely by the capillary pressure(Dont mind this too much). The flow in the two phases are given by: q_o = -\frac{k_o(\Delta P)}{\mu_o}\frac{\partial P_o}{\partial x} q_w =...

An ideal Carnot engine is composed of two reservoirs and a working fluid. The hot Reservoir and the cold one have temperatures ##T_1## and ##T_2## respectively, with ##T_1>T_2##. The working fluid is in a phase transition and has temperature ##T_1## at the start of the Carnot cycle. It undergoes...

I've always been taught that in a piping system (only water), if the flow rate doubles, then pressure loss quadruples. But when using the Darcy-Weisbach equation I often find that it is closer to triple. Playing around with viscosity and temperature I've never been able to bring the ratio higher...

Hi, I used a blower to flow air across an open duct through a nozzle. By using a gate valve, the mass flow rates were controlled. I took measurement in 3 different locations along the ducts. But, why by decreasing the mass flow rate, the air velocity was increased? It is just happened for the...

Hi, I have a problem following the solution of a linearized potential flow equation in a publication by Fung. The problem describes potential flow over an oscillating plate. A boundary layer is approximated by defining a subsonic layer over the panel and supersonic flow above the subsonic...

A question was posed to me with the following diagram. http://imgur.com/6ltYKd5 11 Sprinklers, in series with identical heads, but 10 and 11 displaying a much smaller spray pattern. 1. Is this possible, and under what circumstances. 2. What would a good solution be to prevent this? My...

I've been doing some bedtime reading in Chabay & Sherwood's Matter & Interactions textbook (https://www.amazon.com/gp/product/0470503475/?tag=pfamazon01-20) and have come across some interesting tidbits. Here they are: I've always pictured electrons pushing each other through a wire, kind of...

where i can found an example A FORTRAN control volume finite element method code FOR FLUID FLOW PROBLEMS thanks for help

Homework Statement Water exits the 3-in.-diameter pipe at a velocity of 12 ft/s and is split by the wedge diffuser. Assume water is ideal fluid, that is, incompressible and frictionless. Determine the force the flow exerts on the diffuser. Take θ = 30 ∘ Homework Equations F = ρAV The Attempt...

Homework Statement A tank of cross-sectional area A is initially filled with fluid of density ρ and viscosity μ to height hi. The pressure above the fluid in the tank is atmospheric, Patm. At the base of the tank there are two pipes, which are both open to teh atmosphere, such that fluid...

I've forgotten a lot of field theory so I've been rereading it in a couple of electric field theory textbooks. What seems like a simple problem falls between the cracks. I hope some readers can help - it will be appreciated. My application seems simple (solution will require numerical FEA but...

Hello, I would like to know how to calculate the drag force per unit length of an infinite cylinder with it's axis parallel to the flow field, I had read about a post here previously titled " Drag force on cylinder in parallel flow" but the slender body approximation is not valid for inifinite...

Ok, I'm trying to simulate a circuit containing a diode and I am a bit confused. I thought the arrow direction on the diode symbol shows which direction the current is able to flow through it. However, in my simulation, it is showing that the diode is limiting current flow in the exact...

< Mentor Note -- please remember to use the Homework Help Template when posting schoolwork questions > Consider the fully developed laminar flow due to gravity of water in a vertical circular tube. Assume atmospheric pressure at inlet and outlet. Show that the relationship between diameter and...

Hi! I read from Perry Green's ChE Handbook that the friction factor for Re ≤ 2,100 can be approximated by ƒ = 16/Re. But there was this question that I encountered (though I don't know the source) and according to it, ƒ = 64/Re for laminar flow. Can someone clarify which is which? Thank you!

Hello, thanks in advance for your help, I am not a physicist, however have a fairly good grasp on mathematics, also this isn't homework or an assignment but a real world problem. Currently trying to create a system with a nebulising gas at a linear velocity of 350 m/s. The calculations...

How is entropy related to flow velocity? Does entropy change with when flow velocity changes ? I have a questions to solve with determines pressure, temperature and flow velocity at two points and Flow Direction is required to determine. Please help me with the question