Steady Definition and 255 Threads

I have a homework problem that I need to use the steady periodic oscillation to solve, so instead of having help on the problem I'd rather just understand how they did it then apply it to my homework (I think that's alright?) I'm kind of wondering where my book gets this from...

Hello, Here is a homework problem that I have been working on. I am wondering if for the mass balance of substance A, do I include the terms in the reaction rate that involve species R and B? Also, wouldn't A and B start reacting in the pipe before they even go into the CSTR? (I guess put in...

How can we make the assumption that the Galaxy is approximately in a steady state at the present time? I read this from the textbook: "the time required to complete one orbit at 10kpc is 3×108yr... a typical disk star has completed over thirty revolutions, and hence it is reasonable to assume...

Homework Statement Find the steady-state motion of the mass–spring system modeled by the ODE: 4y''+12y'+9y=225-75sin(3t) Homework Equations for a diff eq modeled as: my''+cy'+ky=F0cos(ωt), yp=acos(ωt)+bsin(ωt) a=F0*(m(ω02-ω2))/(m2*(ω02-ω2)2+ω2c2) b=F0*(ωc)/(m2*(ω02-ω2)2+ω2c2)...

when we electric field between two conductors in certain direction the current density should pass in its direction why current density direction change at boundary although the direction of electric field is the same for both conductors

Although I understand the derivation of boundary condition in case of steady electric current but I did not understand, that the electric field which is in direction of J current density which is generated from permanent potential to have a current in a conductors that is applied between two...

Hi all, can i know is it true that charge flow is equal to zero at steady state current? Or is the rate of charge flow equal to zero. Thanks :)

Hey! When a stream is steady-state, you can cancel the acceleration term in navier-stokes equation, right? so: \rho \vec{a} = 0 = - \nabla P + \rho \vec{g} + \mu \nabla ^2 \vec{V} But there are many terms in the total acceleration which are not dependant on time! The acceleration term in...

Hello everyone, I have this setady state, heat transfer problem; I hope you can help me with it. I have flux source of 400 W/m² (a lamp), and i want to calculate the heat flux passing through a surface arbitrarily placed and oriented in the space. There is air in between. How can i do this...

Suppose I am putting a compound A in a reactor where the reaction A → B is occurring. If the concentration of A coming into the tank and leaving the tank are not changing (meaning, the value of C_a in is not the same as C_a out, but C_a out stays the same throughout) and the volumetric flow rate...

Homework Statement a) Determine the phasor current and impedance of the circuit b) Determine the steady-state current i(t). Homework Equations impedance conversion: ZL = ωLj ZC = -1j/ωC ZR = RPolar form conversion: rectangular form = R + jX Zmag = (j2 + r2)1/2 Zangle = arctan(j/r)V = IR...

Hello, I'm having trouble with a conduction problem, I have access to the answer but not the solution. I did it on my own and my value is half of what the answer is. Now, my calculus is a little rusty, but I don't know where I am going wrong. So the dimensions and temperatures of the sphere...

I'm having trouble solving this problem. I'm trying to find the steady state angle of a rod with wind /fluid drag. Assume Cd, L, U, etc. are known. The viscous and form drag forces are a function of the angle θ so I don't have enough equations to solve the problem. Maybe there's some type of...

Homework Statement A flat plate lies in the region: 0<x<35, 0<y<inf The temperature is steady (not changing with time), and the boundary conditions are: T = { x if 0<x<35; y=0 70-x if 35<x<70; y=0 0...

Homework Statement Subpart of the question requires me to find the steady state of the transition matrix: P=\begin{bmatrix} 0.1 & 0.7 & 0.2 \\ 0.1 & 0.8 & 0.1\\ 0.3 & 0.1 & 0.6 \end{bmatrix} Homework Equations We thus need to find vector \boldsymbol{v} in the equation...

Homework Statement Find the steady state temperature ##U(r, \theta)## in one-eighth of a circular ring shown below: Homework Equations The Attempt at a Solution I start by assuming a solution of the form ##u(r,\theta) = R(r)\Theta(\theta)##. I also note that ##u(r,\theta)##...

Nozzle: Why for subsonic flow the cross-sectional area of nozzle decreases?

Hi all, I am getting confused about how to calculate steady state error in a system. My particular transfer function is: G(s)= 4.992/(s^2+3s-1) Firstly, with an input step am I right in saying that the Steady State error will always be zero? If so can someone explain the reason behind this...

Hey, Can someone explain to me how you calculate time to steady rate? Or provide a website that explains it? Not having much luck :( Thanks!

Essentially, this looks like a differential equation problem but being rusty on differential equations I am a little stuck. Homework Statement Consider the following SDE d\sigma = a(\sigma,t)dt + b(\sigma,t)dW The Forward Equation (FKE) is given by \frac{\partial p}{\partial t} =...

I have attached the picture of the circuit. I'm trying to figure out the steady state voltages across the 2 resistors and the capacitor. V_s is given to be 10V DC. At steady state in a DC circuit, a capacitor acts as an open. When that happens, we shouldn't expect any current to flow...

Hi all I am doing a university module on vehicle dynamics and wish to clarify/enhance my understanding of vehicle handling and the effects of weight transfer. Here are a points based some past exam questions and my answers, if anyone can spot a mistake or would like to add anything this would...

Homework Statement I'm unable to solve a problem of heat equation in a cylinder in steady state. The problem is a cylinder of radius a and a height L. The boundary condition are ##T(\rho , \theta , 0)=\alpha \sin \theta##, ##T(\rho, \theta , L)=0## and ##\frac{\partial T}{\partial \rho} (a...

This is the problem: http://oi47.tinypic.com/6qij4o.jpg I set fx, fy, and B equal to zero. 'x' forces: Fx - Bsin(30) = 0 'y' forces: Fy - mg + B(cos(30)) = 0 lower end: -0.5*mg(cos(30)) + 0.4*B = 0 Using the third equation I solved for B, and got -477.4. I then plugged B into the...

Hi all, I am wondering how I plot the steady state temperature distribution of a square flat sheet in maple. I solved the initial partial differential equation I was given and ended up with a function generalized as T(x,y) =(constants)*sum(stuff). Which is a Fourier series representing...

Homework Statement Find Vo in steady state. V1 = 5cos(1400t) V R = 100 Ω L = 25 mH C = 20 μF Homework Equations L = Ls C = 1/Cs The Attempt at a Solution I first solved for the transfer function T(s): T(s) = \frac{LCs^2 + 1}{LCs^2 + RCs +1} From here I can plug in...

Homework Statement Water is discharged from a reservoir through a pipe 700m long. For the first 100m of its length the pipe is 100mm in diameter and then suddenly enlarged to 150mm diameter for the remaining 600m. The pipe terminates in a nozzle which discharges a jet 25mm in diameter at a...

Hi, I'm interested in the theory of an Aluminum sphere that is initially at some temperature that is hotter than its surroundings. The sphere is surrounded by air at some small radius, say one meter, and then the air and sphere are both enclosed by an infinite shell of Aluminum at some...

I have 2 doubts . First one was to figure out how the positive and negative scrub radius will affect the dynamic toe during braking or accelerating . Then it made me realize that to understand this I will have to analyse all the forces acting on the tire (tractive forces) . Then i read up...

I come from a civil engineering background and I'm about to start a masters in nuclear energy. I have no experience in thermodynamics and I've been doing a bit of revision before the course commences to get me up to speed. I've been working my way through 15 revision questions and I only have a...

Hello all, I am trying to solve the FPE in 2D, The equation is (with implied summation over repeated indices): 0 = \left(- \displaystyle \frac{d}{dx_i} D_i^{(1)} + \frac{d}{dx_i}\frac{d}{dx_j} D_{ij}^{(2)}\right) ( n ) where my diffusion coefficients (the D are functions of position...

(1) A mass of 3.0 kg is suspended from a vertical spring and produces a static deflection of 60 mm. The system is also subjected to viscous damping of 36 N s/m. Calculate the value of the: (a) natural frequency i. In Hz ii. And rad/s (b) damping ratio...

Homework Statement Air is to be compressed from 120 kPa and 310 K to 700 kPa and 430 K. A heat loss of 20 kj/kg occurs during the compression process. For air: cv=0.7165 kj/kg.K and R=0.287 kj/kg.K . A) Neglecting kinetic energy changes determine the power input required for a mass flow...

I have a project where I need to solve T''(x) = bT^4 ; 0<=x<=1 T(0) = 1 T'(1) = 0 using finite differences to generate a system of equations in Matlab and solve the system to find the solution So far I have: (using centred 2nd degree finite difference) T''(x) = (T(x+h) - 2T(x) +...

So would the inductance of a inductor be effected if it was in a large steady state magnetic field. Say the inductor produces a field of about .01 Tesla and the large electromagnet produces a field of 1 Tesla or more. How would a high permeable core vs a air core effect it? Would it add...

I was given the following interesting question. A closed room contains several identical machines in it, they are fed by an electrical cable. The machines can be turned on or off. When a machine is turned on, it consumes electrical energy and as a by product generates heat. The heat is...

Homework Statement So this is a bit of a two-part question and I'm unsure which part I'm not doing right (or both!). i) Find the closed loop transfer function of the system shown ii) Design a proportional controller for the system to give a 10% steady state error Any help, hints, suggestions...

Homework Statement At steady state, a stream of liquid water at 20C, 1bar is mixed with a stream of ethylene glycol (M=62.07 g/mol) to form a refrigerant mixture that is 50% glycol by mass. The water molar flow rate is 4.2 kmol/min. The density of ethylene glycol is 1.115 times that of water...

http://dl.dropbox.com/u/33103477/2007%2010b.png I'm can't get my head around this question, there doesn't seem to be enough information to compute a steady state ? Any ideas on how to begin ??

http://dl.dropbox.com/u/33103477/harvesting.png So am I right in saying the 2 steady states are: N_1=\frac{h}{r}, N_2=\frac{1-h}{\alpha} Now plugging in N_1 into the equation I get: \frac{-h^2 \alpha}{r} < 0 So N_1 is stable. But I can't quite figure out how to classify...

http://dl.dropbox.com/u/33103477/model.png Form of the equation \gamma -\delta p_t = \frac{p_{t-1}-\alpha}{\beta} or p_t = \frac{-1}{\delta \beta}p_{t-1} + \frac{\alpha + \gamma \beta}{\delta \beta} So the steady state is p^* = \frac{\alpha + \gamma \beta}{\delta \beta + 1}...

Given the following system (d(t)=0), I'm supposed to calculate the steady state error for unit step and unit ramp inputs respectively. Basically, the open-loop transfer function of the system is \frac { 3s+0.5 }{ s({ s }^{ 2 }+3s+8) } The closed-loop system is \frac { 3s+0.5 }{ { s }^{ 3...

Cubic Population Model with steady states ! I am unsure as what this question means: Consider the cubic population model: dN/dt = cN(N-k)(1-N) where c>0 and 0<k<1 If the the initial populations is N_0 describe without proof the future of the population, distinguish the various cases on...

Homework Statement Consider the steady flow between two long cylinders of radii R_1 and R_2, R_1 > R_1, rotating about their axes with angular velocities \Omega_1, \Omega_2. Look for a solution of the form, where \hat{\boldsymbol{\phi}} is a unit vector along the azimuthal direction...

A straight, uniform circular pipe of internal diameter of 88.43 mm and external diameter of 118.38 mm carries hot water at 63.67 deg cel. The pipe has a thermal conductivity of 247 Wm^-1 K^-1. how to calculate the steady-state rate of heat transfer per unit length, in W m^-1, when the outside...

Homework Statement Air passes over an electrical heater at a steady rate of 2500cm^3 per second. The inlet temperature of the air is 20^oC ( 20 degrees celcius ) and the steady outlet temperature is 40^0C ( 40 degrees celcius) a) What heat is absorbed by air passing over the heater in 2...

I know that in an AC circuit at the steady state a capacitor behaves like a short and inductor behaves like an open. Since the inductor is open wouldn't that just mean the answer is 0?

Hey all. I sure hope somebody can assist with this! I am a hobby beer brewer and am writing my own heat control algorithms. Part of the process involves heating water to a desired temperature setpoint. I'm using an electric water heater element (5500W) inside the water vessel (~5-10 gal)...

I am trying to understand steady state tracking error. I was looking over one of the example problems in my textbook and this is what it said: G(s) = (-1)/(100(s^2-10.791)) D(s) = K(s+5)/(s+10) Td(s) = 1/s as it states above I don't understand how they got the value 3300... I got 2156 when...

\begin{align} \dot{x} =& -x + ay + x^2y\notag\\ \dot{y} =& b - ay - x^2y\notag \end{align} The only steady states are $(-b,0)$ and $\left(0,\frac{b}{2a}\right)$, correct? I feel like there should be more but I don't think there any.