Flow Definition and 1000 Threads

Homework Statement when the balance point is achieved , there're no current passing thru , so Galvanometer should show 0 . Am i right... so there's no current passing thru the 20 ohm resistor . so my working is ( 8.1/120 )(40) = 2.7 V ... correct me if I'm wrong...Homework EquationsThe Attempt...

I am trying to find out what is the best method / correct formula to calculate Flow rate at inlet/outlet when pressure is known. Please see attached image. any help would be greatly appreciated. Note: Flow Rate can Vary from 100 sccm to 500 sccm.

[FONT=Courier New] Without the salt bridge then there is no flow of charge and there are no electrons flowing in the external circuit.?HOW?i know function of salt bridge is only to maintain neutrality i.e if salt bridge is not there there will be accumulation of positive charge in one half...

Homework Statement [/B] The shape of a car windshield is approximated in the figure below; its length is 2.0 ft and height is 1.5 ft. Obtain an equation of the windshield shape r as a function of θ, r(θ), in the polar coordinate system shown in the picture. When the car moves at 55 mph...

Homework Statement From my lecture notes, here are the equations for convection between two plates. I have derived equations 9.6, 9.7 and 9.8. But for 9.4 there's a problem when gravity becomes involved. Homework Equations Navier stokes: ## \rho \frac{D \vec u}{D t} = -\nabla p + \mu...

A thought came to me while pouring antifreeze into my car today. As I pour in the anti-freeze it fills to the brim and takes awhile to flow through the cooling-system. However, if I choke the hose a few times it for some reason swallows the antifreeze faster. Is this similar to the bottle-neck...

Homework Statement Hi Guys, I am wondering how voltage can flow in an open circuit as I = 0 so surely V=IR; V = 0*R so V = 0 I know it does as when a capacitor is fully charged no current flows yet there is a voltage. I'm about confused thanks! Homework Equations V = IR The Attempt at a...

Hi my name is Federico and I'm a student of mechanical engineering and i have to make a research on this material: waspaloy. Now, i have the flow stress model, but i don't have some constant of this equation. In particular , there are a classic JC model where stress is...

Hello all, this is my first post here, so please excuse me if there are any mistakes or important information is left omitted. Now, my problem is quite intricate and specific so I will be thankful for any information I can get. Using Excel, I am looking to model the volume flow of air through...

I have made a pitot tube that I am using to measure the velocity of air in a pipe. First, I placed the probe into the pipe such that the hole in the probe was parallel to the flow to obtain static pressure. It did this successfully and I proved this using a piezometer. However, I then turned the...

Hi guys, (I apologize if I'm wrong here, and I apologize for my bad English but I'm Italian): if I have two container, where: container "A" (there is "He" with a pressure of 2 atm); container "B" (remember "O2" with a pressure of 1 atm). 1) you tell me which formula to use to calculate the speed...

Hello, I was hoping someone on here could suggest some affordable software to model the flow produced by a ducted fan. I saw someone using Solidworks flow simulation, which is convenient because I can use SW to model the fan AND get a rough estimate of the thrust produced. I'm not looking for...

Homework Statement Water (η = 1.00E-3 Pa·s) is flowing through a horizontal pipe with a volume flow rate of 0.0125 m3/s. As the drawing below shows, there are two vertical tubes that project from the pipe. Assume that H = 0.0458 m and L = 0.738 m. Calculate the radius of the horizontal pipe...

So Volume Flow Rate (Q) = (P2-P1)/R where R is the total resistance of the system. R is directly proportional to Length and inversely proportional to surface area, and the inherent resistance (viscosity) of the fluid. But R =nL/r^4. r^4 rather than r^2. So there has to be another factor...

Basically, I'm modelling the flow of a "coating" process -- a fluid flow between a flat moving plane and a stationary cylinder, 2D, cartesian coordinates. Subscript 0 is the at the minimum height b/w the plane and the cylinder, and subscript c is at the point at which the flow leaves the moving...

I would like to know how carriers flow in a bipolar junction transistor when working in saturation mode. Normally, electrons would flow from the emitter to the base. Then, from the base, some recombine with holes nad leave, forming the base current, and the others (the majority) diffuse in the...

I have an assignment involving a duct vent and turbulent flow. Flow enters a duct vent of a certain cross-section, it then reaches another section with a smaller area, at the beginning of which there is a horizontal plate that is radiating heat. It's a 2D problem. Fluid is Air, inflow T=20C...

Homework Statement Process water with a specific heat capacity of 4.182 kJ kg–1 K–1 flows at a rate of 0.050 kg s–1 through a heat exchanger where its temperature is increased from 16°C to 85°C. Heat is supplied by exhaust gases (mean specific heat capacity 1.075 kJ kg–1 K–1) which enter the...

Homework Statement i) A particular source of potential difference is capable of providing a maximum potential difference of 2 Volts. Sketch how you would connect two such sources to provide a potential difference of 4 Volts. ii) If each source can provide a current of 20 mA before its...

Hello, I went through a problem in my reaction engineering textbook, and solved them correctly by basically mindlessly plugging into the equation, but now I wanted to get some help interpreting the results. So we had a reversible, elementary gas phase reaction that is isothermal and isobaric...

Homework Statement [/B] A 1.5 volt battery is short-circuited by a 2–meter long wire having a resistance of 0.02 ohm per meter. How large is the current flowing through the wire (before the wire or the battery burn out)? Homework Equations Voltage = Ampere x Resistance Ampere =...

Right, I'm sure this is bread and butter to a lot of you but I have just been introduced to the SFEE. mgz+0.5mC^2+H +Q = mgz + 0.5mC^2 +H+W Where Q is the heat transfer, W is work done and H is enthalpy. Where is it assumed that the heat energy is in the energy balance? If heat is added where...

I have a small conductive, non-magnetic particle in which I will induce a fairly strong electromagnetic field into using a flow of current. I will then disconnect the power source that makes the particle electromagnetic. How long will it take the magnetic effect of the particle to diminish...

Hello, I do not really know if this is the right place to post this message ... if it's not then I'm sorry I am looking for a valve that allows the flow of liquid but prevent air escaping out form let's say a sealed container ... Is there such a thing?

Homework Statement The cross section of a 20 cm thick, 3 m wide, and 1 m high composite wall is shown. The conductivities of materials A, B and C are 1.0, 0.1, and 0.05 W m-1 K-1, respectively. One side is exposed to air at 295 K with a heat transfer coefficient of 4 W m-2 K-1, and the other...

If I'm losing 30 psi every 20 seconds at a pump, how many gallons am I losing in that time frame? I don't really have a lot of information to go on, which is frustrating. I know the diameter of the pipe is 8" and there's a total length of 500 feet of the pipe. With this info I'm having trouble...

Homework Statement Consider a large plane wall with thickness L whose thermal conductivity varies in a specified temperature range as k(T) = k_{0}(1 + \beta T) where ##k_{0}## and ##\beta## are two specified constants. The wall surface at ##x=0## is maintained at a constant temperature of...

Hello :-) I can't seem to get a good understanding about a part of transistors and how they act. What I think I know about transistors now is as follows: They're made up of npn or pnp called emitter, base and collector, and the junctions between them are emitter base junction and collector...

Homework Statement Write down the complex potential for a source of strength m located at z=ih and a source of strength m located at z=-ih. Show that the real axis is a streamline in the resulting flow field, and so deduce that the complex potential for the two sources is also the complex...

Homework Statement The same question was asked on this forum about two years ago, however I did not find any of the given answers clear. The question was the following: A small pond has a layer of ice 1cm thick floating on its surface. The air temperature is -10C. (a) What is the temperature...

Homework Statement When the rate of blood flow in the aorta is 5 litres per minute, the speed in the capillaries is about 0.33 mm per second. If the average diameter of a capillary is 8 microns (0.008 mm), calculate the number of capillaries in the circulatory system. Homework Equations Flow...

Homework Statement The problem is here: Homework Equations q = heat flow k = thermal conductivity q = -k (dT/dY)The Attempt at a Solution While this is quite an easy question, I just want to verify that I'm doing it correctly. Would it be correct to begin at the bottom of the rock layer...

I was wondering why when the blood vessels constricted the speed of the blood decreased? I thought that since the flow rate has to be the same, the volume of blood that reaches a smaller area from a bigger area will increase in speed and hence decrease in pressure? Perhaps is this due to the...

Hi there, I have a double-barreled question for you all. So I have two pipes connected to each other. The first pipe is 0.64cm and has a Re = 5000, the second pipe is 4.5cm and has a Re = 700. The two are connected so that the gas expands from the the first pipe to the second. Now, I wish to...

0http://math.stackexchange.com/questions/946493/solve-for-pressure-drop-across-and-orifice# I'm running 1/2" pipe but the only way to connect a 9/16" flow switch is with a 1/4" adapter. I'd have to go from 1/2" down to 1/4" to the 9/16" flow switch down to 1/4" back to 1/2". I was wondering if...

Hi all, I am relatively new to compressor theory and I am looking for a good explanation as to how volumetric flow affects pressure ratio between the stages within a centrifugal compressor. My current knowledge is that as volumetric flow decreases, pressure ratio increases as stated in one of...

With a given 2kW pump That pumps a liquid with a density of 820kg/m³ from one tank to another that's 30m higher. With a calculated change in pressure to be 241.3kpa. Find the volumetric flow rate. I feel like there are not enough given variables for this problem. What do you think?

Hi! Been lurking around here for a while but joined today :) My question is about heat transfer in low pressures. I have an object in a vacuum chamber that is much smaller than the mean free path of the air in the chamber. However, the general dimensions of the chamber are much larger than the...

If I have water being pumped through two lengths of pipe, both at 50 psi, but one pipe is 1.25" diameter and the other is 10" diameter, approimately how many gpm will be flowing through each pipe? Thanks in advance!

i am trying to develop a Parabolic Velocity Profile in 3D tube/channel flow. for the 2D case i use u = 1.5*Um *(1-(2y/H)^2) where Um= fluid velocity y = position of solid on "y" axis (x,y) H = width of channel The above equation is not possible to used for 3D case (x,y,z). i try to...

My chemical engineering is a little rusty after 25 years and I could use a little help with this real world problem. This isn't my project but I've been asked to advise. Sorry for the limited information. We have a 30 gallon tank with 75% hydrogen/25% nitrogen mixture at 100 psig. From the...

With work I have not had much time to research this much myself. I was wondering if anyone could give me a link for an article or book that details the process and why's of this calculation; maybe also a short explanation. Thank you in advance, -Tyler.

Hello, Long time lurker, 1st time poster. I need a sanity check that I am solving this problem correctly. I have a pipe with a combination of gas and liquid flowing through it, the density of the gas (ρg) is 5.5kg/m^3, the density of the liquid (ρL) is 435 kg/m^3. I have a vapor...

For a project in my 3rd year hydraulics course we have to design a water distribution network for a residential area using EPANET and optimizing it using GAWUP (GANEO). I have the entire network set up with all the peak flow demands set for each of the required nodes. Using GANEO I can easily...

hello first of all i'd like to appologise for eventual speeling mistakes i am going to make in this thread :D ive chosen as subject for my maturity paper the coanda-effect applied in the common experiment with water flowing along the curved-convex surface of a spoon. i want to make a model of...

I am designing an almond dehydrator as a part of my university project and need some advice regarding air flow in the dehydrator. There is a hollow perforated cylinder with a heating device in the middle. This cylinder is divided into two sections. The lower section has to take in cool air...

Homework Statement A hair dryer is basically a duct in which a few layers of electric resistors are placed. A small fan pulls the air in and forces it to flow over the resistors where it is heated. Air enters a 900-W hair dryer at 100 kPa and 25° C, and leaves at 50° C. The cross-sectional area...

Homework Statement A current-carrying ohmic metal wire has a cross-sectional area that gradually becomes smaller from one end of the wire to the other. How does the current vary along the length of the wire? Homework Equations a. It increases. b. It remains constant. c. It...

Hi, If you are entering motor load data (Real and Apparent Powers) into a power system analysis software so that a load flow analysis can be conducted and you are calculating these powers based on current and voltages, do you assume and use the full load power factor for the motor, as...

Hi all, I am studying for the MCAT and a section in the book lists the equations dT= IR dP=QR dV=iR For thermal, fluid, and electricity flow respectively. It then goes to state that a thicker conduit allows for greater flow. That part makes sense to me because a larger diameter pipe has...