Transient Definition and 170 Threads

Homework Statement For the below circuit, the switch was open for a long time. Find the current Ia(t) for t>0. All capacitors are initially uncharged.Homework Equations Complete response of a capacitor: v(t) = Voc + (v(0) - Voc)e^(-t/τ) Combining parallel capacitors: summation Current through a...

A problem from a heat transfer book with conduction and radiation led me to a differential equation like this: T'(t) = a - b*T(t) - c*T(t)^4 Although my professor said that there wouldn't be an analytical solution for this one and to get the answer by an iterative method I got curious and...

Homework Statement The circuit shown in Figure 5 contains two emfs of opposite polarity E1 = 40 V, and E2 = -20 V. The circuit also contains a switch, resistors R1 and R2, and a capacitor C.The capacitor is initially discharged. The switch is connected to position ‘a’ for a period of 8...

I AM DOING A PROBLEM ABOUT TRANSIENT HEAT TRANSFER AND IT SAYS: "A solid sphere of steel has 1 cm of diameter and a initial temperature of T0 =15 ºC. It is placed into a flow of Tinf = 60 ºC where the convection heat coefficient is h = 2000 W/(m^2K): (Density of steel rho = 7832 Kg/m^3 ...

Say you have a furnace wall at a temperature at 400 degrees C and you have oven gas at 200 degrees C and you place an copper rod into the furnace. The copper rod has an initial temperature of 25 degrees C and a length of 1 meter and a diameter of 2cm. You want to find what find the time it takes...

Hi guys I just stepped into the electronic fields, I have some problems confusing me a lot I read my lecture notes but I was confused by a term transient response modes From my lecture notes, it describe this term in linear/first order and second order system But I'm still confused Like...

Homework Statement Consider unsteady state heat conduction through an infinitely wide slab of solid material of thickness 2L. There is no internal heat generation and the thermal properties of the material are independent of temperature and position. Starting from an energy balance, show...

1. The problem statement: What is the value of capacitance needed in Fig. 1 so that the voltage across the capacitor never exceeds (a) 200 V, (b) 20 V, and (c) 2 V ? This is the Circuit Homework Equations Vc(0-) = 0V Vc(0+) = 150V ic = c v' vc(t) = final + [initial -...

Hey, I know you have a rule requiring an attempt at the problem before posting here. The trouble is, I have a department required simulation project due this Wednesday and my professor is very behind in her lectures and has yet to even mention transient circuits. I don't expect this...

Hello! For those that were with me at signals, I passed the exam, but barley. 10,5 points out 20. Going to cancel that exam and do it again when I have the chance. But anyway, back to the topic. I am trying to get the intuition for transient processes in RLC circuits. I was taught...

Hello, So is there any software, that generates the differential equation for the input circuit? I am trying to solve a problem and I want to check if my equation is right. Thanks.

Hello all: I'm a newbie, trying to write/use code for solving a 2D advection-diffusion problem. I'm not sure how many boundary conditions I should have for the property that is being transported. In my problem, I have diffusion switched off (advection only). The property being...

Homework Statement In the circuit shown below the switch has been opened for a very long time and closes at t = 0. Calculate the output voltage VO at: 1: t = 0−; 2: t = 0+; 3: t = t1 = 24 µs; 4: t → ∞. In the circuit shown below the switch has been closed for a very long time and...

Please Help! Trying to decipher transient flow results Hey guys, I'm currently studying a Bachelor of Aerospace Engineering and doing my honours level research project in a field called Active Flow Control. A brief intro to what the project involves: The motivation of the project is to...

My geometry is bit complex. I want to make a heat transfer model based on FDM in the radial direction. But it has become very difficult to discretize the domain because of multiple materials. As the segments are symmetric, I want to model the heat transfer in one segment. My schematic is given...

Let X be a Markov chain with a state s that is absorbing, i.e. pss(1) = 1. All other states communicate with s i.e. i → s for all states i ∈ S. Show that all states in S except s are transient. I understand this intuitively, but I'm not really sure how to start the proof.

Hi, I have to model a transient thermal problem in Ansys. I just need an outline of how I should proceed. The Problem: I am trying to model the cooling of a solar collector reciever tube from 150 degree celsius to ambient. My attempts have involved the following: 1. Initial condition...

Hi All, I'd be grateful if helped in this understanding; I'm following the attached pages to solve a numerical problem by Forward difference, backward difference and central difference- in fact to be precise, deriving the transient solution approach to a heat transfer problem--- In the...

Hallo, I have been trying to find some bibliography about this issue, but all what I found it is very simple and always discarding the effect of the Thermic Capacity of the elements. I have to work with matherials which operate in transient conditions and which have parts which accumulate...

Hi, I have written a numerical code to solve the 1D heat equation in cyclindrical coordinates: \frac{\partial T}{\partial t}=\kappa\left(\frac{\partial^{2}T}{\partial r^{2}}+\frac{1}{r}\frac{\partial T}{\partial r}\right) The problem I'm considering is a hollow cylinder in an infinite...

I'm trying to marry the concepts from my EM course with what I've been doing in my lab course. Correct me if I'm wrong, in a plain RC circuit, when closed with a DC source, the capacitor initially acts as a short (voltage is zero across the terminals, while I is max), until after a few...

:bugeye: http://www.pnas.org/content/107/40/17194

Hello Guys, I am planning to design electrical grid connected with solar distribution generation system using ETAP. I tried to run trasinet stability analysis of this system with fault at each and every line/branch of the system, to get corresponding critical clearing times. I realized that...

I need someone to tell me if what I am saying is true or BS? Switching Frequency: Is simply defined as the frequency (amount of times) the same operation occurs, in our case the amount of times per second each phase is switched on. Duty Cycle: is thought of as the time the object is on...

Hello All, I have to do a transient analysis of thin composite film. Following are the requirements: 1. Time t=0 to t=0.01, Initial condition of Temperature=300 K. 2. Time t=0.01 to t=0.05, Temperature=505 K. 3. Run the analysis from t=0.05 until a stable solution is obtained. I tried...

1. A large block of steel [k=45 W/m°C, alpha=1.4x10^-5 m2/s] is initially at a uniform temperature of 35 C. The surface is suddenly exposed to a constant heat flux of 3.2x10^5 W/m2 Find the temperature at a depth of 2.5 cm after 30 seconds has elapsed.

Ok, my apologies if this has been dissected on PF before, I did do a few searches and didn't stumble into anything, there doesn't seem to be much info online. Is it woo-woo or legitimate ? ----- Unexplained Weight Gain Transients at the Moment of Death Journal of Scientific Exploration...

Hello All, I have a bit of a problem with a series RLC circuit with no supply voltage. In the process of actually solving the second order differential equation for the voltage across the capacitor I have lost a handle on what it actually represents in terms of the circuit. I have attached...

Homework Statement Find the general solution of the given differential equation. Give the largest interval over which the general solution is defined. Determine whether there are any transient terms in the general solution. Homework Equations x(dy/dx) + 2y = 3 The Attempt at a...

Homework Statement Find T,K value such that the system's percent overshoot is .254 and peak time is 3 http://img560.imageshack.us/img560/6139/problemz.png Homework Equations [PLAIN]http://img46.imageshack.us/img46/51/releq.png The Attempt at a Solution...

please explain the transient and subtransient reactance of synchronous machines

Okay, since the most fluids I've studied are from the Euler equation in the context of plasma physics I may be asking a trivial question, but here goes anyway. What I am wondering about is why there is a transient response when I cap a straw with my finger, place the straw in water (while still...

Homework Statement Battery Voltage = 12 V, C = 1uF, R = 1Kohm, L = 0.2H. Find Transient Current. See Fig for more details. Homework Equations i = Cdv/dt. The Attempt at a Solution (I think the problem doesn't make sense)

Homework Statement "Consider the tank and water supply system as shown in the figure below. The diameter of the supply pipe, D1 = 20 mm, and the average velocity leaving the supply pipe is V1 = 0.595 m/s. A shut-off valve is located at z = 0.1 m, and the exit pipe, D2 = 10 mm. The tank...

Homework Statement Homework Equations ordinary mass balance The Attempt at a Solution So far I have gotten: d[rhob*V]/dt = Min - ?

Considering an engine generating thermal heat at 140 kw and when the generation starts the thermal equilibrium of the engine will be distrubed , a radiator is installed to cool the engine this radiator cool the engine through flow of water and water is cooled inside a heat exchanger with air ...

Hi everyone, I'm currently working on coding a finite element heat problem in Matlab that is as follows: I have a cross section of a beam made of an isotropic material (concrete) that is placed in a furnace, and the outside temperature is raised at a constant rate. I am interested in...

hello friends... i am having following problem in this question. first i don't understand how they have calculated R equivalent=5/6.i think its value should be 25Kohms. will it be different at 1ms and 4ms or same ?\\ i shall be thanks to u . in one picture is the problem n in other...

Hi guys. I am a Mechanical Engineering Student but we've a course called Control systems. My question is why does any system(physical like fan,motor or electronic like amplifier) have a TRANSIENT RESPONSE and specially why do electronic components like amplifiers,diode or for that matter any...

If the blood pressure jumps from a long term pre-hypertension stage (140/90) to 175/110 for ten hours, and then calms down to pre-hypertension stage again, are there any long term effects on the body for sustaining such high blood pressure? From what I've been able to find out, high blood...

Homework Statement For my internship I need to solve a problem with eddy currents involved. The problem shows a U-shaped aluminum slider (see attachment) with steel plates on the left and right side mounted on it. In this aluminum slider there are 10 magnets (5 at each side) with a...

I need a fem code either in MATLAB or fortran to refer to as I am stuck at some places. Please help.

Hi Anyone with experience with transient heat transfer please can you help me. I have attached an image that is a simple stirling engine schematic. One half is essentially a pipe that is heated from one end and kept at room temperature at the other end. Inside it is a displacer that is not...

Hello. I am watching this video: https://www.youtube.com/watch?v=xIQtnQ9XPbE and he says there: I see that the wave turns into a "normal" sinus in the end, but it's not constant. I think, that even on an unmatched transmission line, the waves should go back and forth, but eventually...

Hi, I have been quite confused about this for sometime now. It has not been mentioned clearly in the books/references that I have looked into. In transient thermal analysis using FEA with implicit scheme or the Crank Nicolson scheme, are there Newton Raphson iterations based on the...

Hi, I am studying the heat transfer in a stirling engine. The basic situation is a pipe blocked off at both ends, with air inside, and a displacer also inside, that moves backwards and forwards inside. It is not tight against the walls of the pipe, and air can pass around it. One end of...

Does anyone have a solution for the heat transfer from a pipe into a solid. I am looking for the temperature in the solid based on radius and time and also the heat transfer based on time. The temperature in the pipe (surface of the solid) is constant. The solid has a constant lower temperature...

hi all.. How can i describe initial conditions or initial forces in comsol(like wave forms such as ramp or parabolic)? I couldn't find it in the manual. in ansys, i do it in time steps(in solution options).(like t=0, F=10 t=0.001 F=0) I tried to give initial displacements to the points but...

Laplace help on a DC transient RC circuit ? PLEASE -------------------------------------------------------------------------------- I HAVE A RC CIRCUIT WHERE R1=100Kohm and R2=1Mohm and C=2.1micro farads with a Vin =10V, In order to calculate the voltage through the capacitor I...

I HAVE A RC CIRCUIT WHERE R1=100Kohm and R2=1Mohm and C=2.1micro farads with a Vin =10V, In order to calculate the voltage through the capacitor I deduce the following formula, Vc(s)=V/S {(((R2×1/Cs)/(R2+1/Cs)))/(((R2×1/Cs)/(R2+1/Cs)+R1) )} I then need to produce a laplace transform...