Flow Definition and 1000 Threads

I have a basic question for my own understanding of things, Consider a straight horizontal piece of Ø15 mm pipe (inside), 20 meters in length, with 5 bars static pressure connected to a water main. Trying to find out what the flow rate through the open end of the pipe will be, doesn't seem to...

I am trying to model fluid flow and losses through a component (e.g., pipe) using REAL GAS properties since 1) I have access to RefProp from NIST, and 2) I am dealing with refrigerants, which are far from ideal. I have seen nowhere an analysis of fluid flow losses (e.g., drag, friction...

Homework Statement A valve is required to regulate the flow of natural gas. Details of the gas are given in table below. It can be assumed that the pipe size and the valve size are the same [i.e. piping geometry does not have to be allowed for]. The chosen valve type is the V250 rotary ball...

Homework Statement Calculate the equivalent choked flow of propane through a particular valve if the choked flow of natural gas through it is 10 litres s–1.The relative density* of propane is 1.45 and that natural gas is 0.65.Homework Equations Kvf = qv (SQRT d/DeltaP) ...1 d is fluids...

Homework Statement [/B] When the level of water in a reservoir is too high, the water spills out over a spillway, as illustrated in the figure below Neglecting viscosity, show that the water flow ##Q## over the spillway is given by $$Q=\frac{2}{3}w\sqrt{2gy^3}$$ Homework Equations [/B]...

I want to use a pump to have solution moving through a reaction vessel at a set flow rate. But the problem is the outlets FROM the pump are very small 1/6" (0.4cm) inner diameter, and the vessel INLET is GL14 thread size (1cm inner diameter). Schematic Problem Pump...

Homework Statement If 5% of the heat available for steam production is lost to the atmosphere, determine the amount of steam raised per hour when the total flow of flue gases is 1400 kmol h-1. qmH = 1400 kmol h-1 Flue gas temperatures: Inlet = 1832°C Outlet = 300°C Water temperature: Inlet...

Homework Statement For QB , why shouldn't the QB = red part only ? Homework EquationsThe Attempt at a Solution Is there anything wrong with the solution given ? Since When we 'cut ' the boards , the b is the red part which in contact with the other board , right ? [/B]

Homework Statement Homework Equations Bernoulli: p1+½ρU12+ρgz1=p2+½ρU22+ρgz2 Continuity: Q=U1A1=U2A2 Area=CC*(¼πd2) The Attempt at a Solution [/B] I attempted to apply the Bernoulli equation, making point 1 the top surface of the left hand side and point 2 the instant at the sharp edge...

Hello everyone, First of all I am new here~ Second, I would like to "prove" on COMSOL that soundwaves (sound vibration) can alter/reshape the fluid flow Can someone tell me the physics i should use as well as all the other parameters to make it work? if someone is more experience can they...

In the figure , we can notice that the moment due to Pe is counterclokwise , but moment due to shear flow is also counterclockwise , How can the Pe prevent the twisting of the beam ? Or is the direction of the shear flow wrong ? Should it flow from the below to the top ?

I am having trouble understanding why blood flow rate is constant between the aorta and the sum of capillaries/sum of the arterioles. I keep thinking that in the arterioles or capillaries there is a decrease in velocity and somehow this decrease in velocity will decrease the total amount of...

I just want to know what would reduce a magnets strength or stop it with a material over it so that its not magnetic anymore. Is there a material that would not allow two magnets attaching N+P from colliding together and make them not move. 1 More question. Is there a electro magnetic device or...

I am working on something that I could use some help with. I have a flow sheet for some fuel injectors that gives fuel quantity through the injector with a set pressure and activation time for 4 different points with different activation times and pressures. I need to come up with a formula to...

I've never done a question similar to this one, and I've found myself stuck on it for a while now. I was hoping for some guidance on where to begin, because I truly have no idea: An incompressible fluid flows through a porous cylindrical shell with inner and outer radii R1 and R2, respectively...

Hi, I am not science student. Can anyone help me to solve this? Density and velocity of a fluid is given as 920kg/m3 and 5m/s, this fluid is flowing through an area of 25cm2. Calculate the mass flow rate? I am in search of some easy unite conversion tricks also.

https://drive.google.com/open?id=0B3IenBvKWb4PZW9rRWg4cXptT2c I had to find the resistance of this circuit between A and B. My teacher said that since the blank wires have zero resistance, the potential difference across the ends of the blank wire is zero(according to v = ir) and thus 1,4 are...

So, I am new to here and I am currently a technician that does vacuum systems for the semiconductor industry (mainly Electrical). I came across something today that has me quite perplexed. So We have this system that flows gas through 1/4" stainless tubing to a pump to dilute gasses and...

I used to have a slide chart that gave gpm through a level section of pipe (1/2" - 6") by measuring how long the exit stream was when it had dropped 4". Imagine a framing square with the blade on the pipe and the tongue hanging down in the stream. Slide the square out until the stream is...

Hi, I have a tank of air which has been depressurized to 0.2bar (absolute) via a vacuum pump, where air can be let in from atmosphere through pipework controlled by a valve. What would be the equation I can use to determine the flow rate into the tank with time? As the flow rate is determined by...

Homework Statement I'm running a simulation and was given 2 mass flow rates (let's say m1_dot and m2_dot) for 2 chemical species at the inlet. Homework Equations mass flow rate = density*velocity * area The Attempt at a Solution I need to compute the bulk velocity for the fluid (consisting...

Dear all, I'm wondering how a control valve can control pressure and flow rate. I understand that a control valve in a pipe induces a certain pressure drop but I don't understand how this affects flow rate. I'm disturbed with the continuity laws which states that the total flow rate between two...

First off, I'm a pathology resident, so it's been a long time since I've done real physics. But I really like physics and I try, whenever possible, to at least develop a basic understanding of the physics underlying physiology. With that as prelude, this question was inspired by blood flow but I...

If the single phase flows on the inclined surface and this phase (let's say water) is wetting the surface then closest layer to the surface will be bounded and will not move. And velocity of flow will be in inverse proportion with viscosity of the fluid. If now the second phase is introduced...

I am hoping this is the right place to post this. I have a hydraulic system that uses two pumps. Each pump is capable of producing 22.5 gpm. With out taking into account the different valves, restrictors, and pipe sizing, my question is, does my gpm double to 45 gpm or stay at 22.5? the pumps...

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...

Hello all, I have browsed this forum occasionally when I had questions and threads showed up on a search. I have been stumped by a problem, so I decided to create an account and see if anyone could help me out! 1. Homework Statement A coal barge 1000 ft long and 100 ft wide is submerged in a...

Homework Statement I am using the NASA CEA code to generate Isp and thrust data for the SSME. I solve the problem twice, once with a frozen flow condition and a second time with an equilibrium flow condition. However, there is a third request for solving the problem with equilibrium flow from...

I am a high school student interested in electronics. I have been able to understand almost everything about electricity and digital computers mosfets, logic gates,memory,cpu, fetching ,decoding, executing ,clock cycles, etc. except there is one thing that I can't seem to grasp my head around...

Homework Statement for shear flow at D , the Q = Ay , i tried another method , i gt 30000 , instead of 29750, why the ans is different from 29750? why can't i use this method( i break the shaded area into 3 parts ( as shown in figure) Homework EquationsThe Attempt at a Solution Q = Ay =...

How to convert volumetric flow rate to mass flow rate?

One thing that has always puzzled me is the fact that in a venturi, air accelerates as it approaches the narrow part of the structure. there are those that argue with the fact that pressure has to raise first , because as we all know, acceleration has to be caused by an increased force (...

I need 250 m/s of airflow speed in a wind tunnel. I can assume for this purpose, the test section of the wind tunnel has uniform flow. However, the wind tunnel can only generate a flow rate of 100 m/s but the pressure can be increased. I am drawing a blank on how could a generic boundary layer...

Hello! 1. Homework Statement I need to find the instantaneous height of a liquid during the simultaneous filling and emptying (through a hole) of a cylinder. I have varying Qin at incremental time of 1 sec. with cylinder area=5 cm and orifice area=0.5 cm. Homework Equations Torricelli's...

Homework Statement In the notes , I don't understand that flange is thin , and the top and bottom surface are free of stress , can someone help to explain please? Secondly , why the q' is assumed to be q ' throughout the flange is assumed to be 0 ? why are they stress free ? We could see that...

Homework Statement You've periodically helped the medical consulting firm Doctors Without Weekends on various hospital scheduling issues, and they've just come to you with a new problem. For each of the next n days, the hospital has determined the number of doctors they want on hand; thus, on...

Homework Statement A fuel gas consists of 75% butane (C4H10), 10% propane (C3H8) and 15% butene (C4H8) by volume. It is to be fed to the combustion chamber in 10% excess air at 25°C, where it is completely burnt to carbon dioxide and water. The flue gases produced are to be used to generate 5...

Hey, I'm working on a project to build a drone which is powered through air jets. The drone needs a valve control system which can control the flow rate (hence the thrust) going to each nozzle in order to adjust it's altitude and stabilty. I need to set up a circuit which can electronically...

Hi, In a standard converging-diverging rocket nozzle, we have (ex.) the relation:(1-M^2)\frac{dV}{V}=-\frac{dA}{A}By substituting in definitions, we can obtain\left(1-\frac{V^2}{\gamma R T}\right)\frac{dV}{V} = -\frac{dA}{A}This shows the dependence on temperature. The relation assumes that...

Hi everyone, I have to answer some question about a physics lab..here are the questions A tank is empty by a pipe and we measure the height (y-y0) of fluid in the tank as a function of time. We obtain this graph ( I join the graph) We can find the relaxation time with the relation : with...

I have to build a digital peak flow meter. I have two models based on calculations ( ideal). I have noticed that the flow rate on the model with a tighter constriction has a greater value than that of a much broader constriction. While testing it out, i noticed air resistance from the first...

I understand in a bulb when electrons flow they cause resistance and this heats up the bulb and the gases inside are ionised and they in turn emit light because their atoms become charged. How does flow of electrons cause sound? I know its an advanced explanation but what is the flow actually...

Hello, I'm interested in building a small non-invasive battery powered device that wraps around a pressured 1/2" pipe for measuring potable water. From https://en.wikipedia.org/wiki/Magnetic_flow_meter and watching youtube videos, it seems they all use electrodes which contact the liquid...

I know I am over thinking this but it's bugging me... When giving patients fluid through an IV giving set, we set the flow rate by adjusting a rolling clamp on the tubing line. This is in effect creating a construction. Reading about flow, I am told over and over that flow is conserved. That...

So, here's the problem I've come up with that I wanted to solve. We're going to be using a polar coordinate system for this one. A will represent our angle theta, and r will represent our radial coordinate. We are going to be looking at a non-compressible Newtonian viscous fluids. I'll now put...

In the principle study of the Pioneer Anomaly, John Anderson and Slava Turyshev suggested a speculative explanation for the apparent deceleration of the spacecraft : as an acceleration of the clock rate used for telemetry back on earth. To be clear, this explanation has been discounted-...

To start this question off, I'll just state what I do understand about potential flow theory 1.) I understand that the navier stokes equations are really difficult to solve analytically except in degenerate cases where the assumptions about the flow cancel out the non-linear terms. 2.) I...

Hello, So I was reading wikipedia the other day, as I do from time to time. I came across a rather interesting sample problem posed in the article, but seeing as Wikipedia is horrible in some of their physics articles on explaining what's the hell they're doing, I became lost. Here is the...

"An adverse pressure gradient strongly favors transition to turbulent flow. In contrast, strong favorable pressure gradients (where p decreases in the downstream direction) tend to preserve initially laminar flow." "High values of M∞ and low values of Re tend to encourage laminar flow" Looking at...

Do all airfoils(infinite wing) have a flow separation at a finite or zero AOA? I wonder if there exists such an airfoil that despite the presence of adverse pressure gradients, exhibits no flow separation phenomena, perhaps turbulent intensity could be high enough to sustain enough speed near...