Flow Definition and 1000 Threads

Homework Statement You open the plastic bottle lid to take a drink,and notice fluid flowing from a small hole in the bottom of the bottle. You put the lid back on and the flow stops. Explain why the flow did not start until the lid was off. Explain why the flow stopped when the lid was put...

Please could someone verify this statement as I understand things: If an object has a low reynolds number (or the fluid is very viscous) then it is dominated by viscous forces and inertia plays no role. The object is in a laminar flow regime. That last part, is it correct? What I'm asking is...

Homework Statement Q.2 One type of bearing that can be used to support very large structures is shown below. Here fluid under pressure is forced from the bearing midpoint (A) to the exterior zone B. thus a pressure distribution occurs as shown. For this bearing which is 30cm wide, what...

Hello everyone! I am new here. I have used this forum on and off through google searches in the past and learned a fair bit from the posts. This is the first time asking anything. The question is probably extremely simple but has been overrun in my head for a week! It is in regards to...

Hi, For my experiment I was asked to determine the length of the tube for a fully developed flow to occur ( Entrance length as shown in the attachment) , with the following flow parameters. Flow rate : 1, 5, 15 lit/min Fluid: Water Tube Id: 1 inch. My question How do I find out the length of the...

Look, I found that there exist two kind of electric current: conventional flow and electron flow. I have read that in every situation I have to use the conventional flow, however I'm going to work with electric circuits using copper wires. In solids, only negatively charged particles (electrons)...

Homework Statement Homework Equations ρ=789, μ=.0012 The Attempt at a Solution From the energy equation we get hf=0.9 We know that hf=f(L/D)(V^2)/(2g) [sorry don't know how to use latex after they removed the bar on the right] Now I can substitute V for Q, but I'm stuck with f and Q as...

How to calculate how much flowrate from blower i can push water pool 2,75m*1,8m down by 1,25m in 1 sec? Note : Blower Pressure 0.03 bar - 0.035 bar There is an empty room above the water pool with dimension of 2.75m*1.8m*1.7m This process happen in a closed chamber...

This thread will concern the workings of potentiometers, but I could use some help tackling something first. I will explain in my next post! Assume I have shorted out a battery with some resistor. I always thought that if you had a high enough resistor value, you could stop current from...

So say if you're in a vacuum, breathing via a space suit (so you're not grounded and are surrounded by perfect insulation) and you touch something with very high voltage relative to you, would you completely safe no matter how high the voltage is? Note I've made the setting a vacuum deliberately...

Homework Statement What is the current flow when a diode is connected in series with a resistor and battery.The cathode of the diode indicated as A is connected to the positive battery terminal.The Anode of the diode indicated as B is connected to the one leg of the resistor and the other is...

Actually i have to calculate the make up water capacity of cooling tower . M= E+B+W . but while calculating the particulars , i am needing the circulation flow rate . i searched it in internet also but it simply showing 18000 so getting confused . Is it 18000 a constant or anything there to...

Hello everyone, I'm new to this forum and this is my first post so go easy! I have an engineering problem which I am uncertain as to how to solve. I am trying to design a basic ballast system for pumping seawater. The idea is to use compressed air to evacuate the water through a series of...

Hi there, I have set up a flow loop for a uni experiment that will teach other students about the bernoulli equation. The loop will use a few working section that will increase and decrease pressure due to diameter, velocity and height changes. I first set-up my loop with the pump at the end...

Homework Statement Consider the following multi-layer wall consisting of an interior insulation layer and an external light-weight concrete layer. Calculate the heat flow thorugh the structure and the temperature at the interface between the two materials. Layer 1: Thermal insulation...

Is the speed of electron flow through a conductor such as copper equivalent to 'c'? I've heard of this being implied several times, but is it a fact? I know it can't be exactly the same as 'c' because we are not talking of energy propagating though a vacuum.

according to this one source, cardiac output (vascular) = blood flow (http://legacy.owensboro.kctcs.edu/gcaplan/anat2/notes/APIINotes5%20cardiac_equations.htm) However, their equations do not match: Cardiac output (CO)= Stroke volume * Heart Rate Blood Flow = cross sec area of vessel times...

Hi all, I have really a confusion between subsonic and supersonic speed evolution when the area decrease or increase I have a problem to understand why in supersonic regime the velocity evolution in a nozzle is adverse of the subsonic regime? for example in subsonic regime, when the area...

I know very little about electricity, but I'm trying to understand it better. I'm trying to wrap my head around something- I have heard it said that, "the flow of electricity through a circuit is due to the movement of electrons". While this explanation sounds simple enough, I have some...

Homework Statement Air at 1 bar and 20°C flows steadily at a rate of 2 m^3/min into a compressor. It leaves at a pressure of 15 bar and 120°C. The heat lost from the compressor is 10% of the work transfer to it. Find these work and heat transfers, assuming that air behaves as a perfect gas and...

I am trying to determine the size of a conductive 2-D sheet that has a specified degree of increased resistance (or reduced conductivity) compared to an infinite sheet. Imagine that electrons enter the infinite sheet and exit the sheet at 2 points which are 1 unit of distance apart and aligned...

Is it possible to have choked flow in a 1/4" diameter pressure regulator with pressure difference of 3.5bar?

is it possible to have a flow rate of 10lit/sec in a 1/4" diameter pipe at 1 bar pressure ?

Does the mass flow rate differ depending on whether it's after the feedwater heaters or before the turbines or is it just constant throughout the entire system?

Is it possible to have a flow rate of 10lit/sec for air in a pipe of diameter 6.35mm (1/4") at a pressure of 1 bar? As in this case, the velocity of air nearly equals the velocity of sound.

Would love to talk to anyonw that is familiar with MKS instruments 1179A Mass Flow controllers. I have taken apart a MKS mass flow controller and am trying to fix it but I am not sure where to get replacement parts, or even what some of the parts do.Most specifically is a small block on top of...

I know that current flows in the opposite direction of electrons but I'm confused as to whether it is the movement of holes like in a semiconductor or if there are actual positive particles flowing that way.

1. Homework Statement Homework Equations CFD The Attempt at a Solution I'm a bit confused by this question. So at first what I do for the problem on the left, I find the changes in the velocities in X and and Y on all four sides. I notice that the values on the diagram to the left are...

Hello everyone, I am quite new to Fluid dynamics, so I would like to ask for your help. Is it possible to calculate volumetric flow rate from the instantaneous pressure? We need to know the flow rate of the air entering the cylinder in the engine due to the suction pressure. It is required to...

Hey! Making a game. Say we have a room of 8*12*3 meters. It has the pressure of 1 atm and suddenly there's a hole of one cubic meter in a wall and outside it's space vacuum. Don't know if it counts how much air is inside the room or if that would be measured in pressure, say we have enough...

Is flow rate at inlet of pressure regulator ( not relief valve) equal to flow rate at outlet ?

Can I say that energy transmitted in DC by electrons flow like ants walking align and in AC by electron vibration like water wave ?

Homework Statement Please see attached. Homework Equations [/B] v = u + at s = ut + ½ at² v² = u² + 2as The Attempt at a Solution I've managed to get the first part of the question applying Bernoulli's principle and then the equations of motion above by considering separately the...

Homework Statement a viscous fluid with viscosity η flows through a circular vessel of length L and radius R under a pressure difference of P. Assuming the flow is laminar, calculate: a)the force on the walls of the vessel. b)the net force on the vessel. Homework Equations Hagen-Poiseuille...

Hello, I am Primarily a Software Engineer, but have some background knowledge from my A-Level and Uni days. However, I have the following problem. I'd like to find out the rate of change in pressure across a valve. Here are the things I know about the system: Cv at 100% open = 0.004 (I...

Hello guys, I need to calculate the flow rate for the following system. 2 lines of CO2 cyclinders at 60 bar. Each line (1/2'') goes to a 1/2'' PSV valve. Downstream the 2 PSV the line are collected together into 1'' pipe. The two PSV are identical and as per datasheet they have the following...

Hi. First of all, I should mention that I'm quite a novice in both physics and engineering. Let's consider an hourglass (or a silo) that is inclined at a constant angle. I'm unsure of how to calculate the necessary diameter of an orifice for a given mass or volume of granular matter to...

I have a setup where there is a source of air pressure, a tube through which the air flows, a connector through which air flows, and a flow meter which reads the flowrate of the air at the end. The final goal is to use the readings from the flowmeter to determine the diameter of the tube through...

Hello there, people! I am quite new here; in fact, this is my first post. I am quite strange to this place. Feeling kinda welcome, though. Okay, so short to the point. I am an 8th grader, and my school just started teaching us about electricity. Well, the basics. I knew much about it, much...

Homework Statement A two component gaseous system has a fundamental equation of the form $$S=AU^{1/3} V^{1/3} N^{1/3} + \frac{BN_1N_2}{N}$$ where $$N=N_1+N_2$$ and A and B are positive constants. A closed cylinder of total volume 2V_0 is separated into two equal subvolumes by a rigid diathermal...

I am doing a lab report and it is to do with compressible flow through rotameters. An upstream and downstream rotameter to measure flow rate with a needle valve between the two. The needle valve acts as a fixed orifice in one part of the experiment. Then the inlet pressure is altered. Plotting...

In the following process flow diagram for the production of hydrogen, why is the amine column placed after 2 heat exchangers?

Homework Statement Hi Guys, I have found that as flow rate increases the pressure difference in the sections of the venturi increases. Would someone please mind explaining in words why as I'm not sure. Homework EquationsThe Attempt at a Solution Well I know that when the fluid gets to a...

Homework Statement (a) Find energy of incoming beam that creates highest cross section (b) What are the differences in the two reactions, using quark diagrams? (c) What would the peaks of the two reactions be like? Homework EquationsThe Attempt at a Solution Part(a) [/B] Cross section is...

Hi, I'm taking a basic electricity course right now and I'm having trouble understanding a formula. The way they have their example makes no sense to me. Can anybody verify that their example is correct and explain a little bit for me? See attached file.

Currently i have a system using bulk argon and i am changing to nitrogen. To trial this i am going to use cylinders of OFN(oxygen free nitrogen). how do i caculate how many cylinders i need based on a flow rate of 16 liters/min. Thanks

is this true? thanks for help. i wished to abstract (generalize on topic) from electric current in physical wires, to for example in air. i hope this is in proper forum section. ---- Electric current's density J depends on electric current's intensity I measured in (A) & on conductor wire's...

I am working on a problem in which viscous flow comes out from an inclined tube, forming some kind of a fountain. In the tube the fluid is Newtonian and the flow can be treated as Poiseuille flow. I want to study the movement of the fluid after it leaves the tube. Can someone point me about the...

Hi, Could you explain the reason why the velocity varies in the wake region behind the cylinder in "flow over a circular cylinder"? the velocity variation is, minimum at a point parallel to the centre point of the cylinder and increases to free stream velocity as the vertical distance increases...

Homework Statement See Fig.2.4a, let the gases flowing through the nozzle control volume be perfect with Cp = 1.004kJ/kg.K Determine V9 if T5 = 1000K, T9 = 670K and V5 = 120ms^-1. Homework Equations I've detailed the equations in the attached pdf for clarity. The Attempt at a Solution See...