Cycle Definition and 617 Threads

There is a technical document in reactor operation which contains neutronic calculations to predict reactor situation in different power lever and effective power days. Operators use this document which usually called Album of Reactor Core Neutronic to operate the reactor based on that. This...

Hi, I compute sum of energy in a cycle and I don't find 0, could you help me to find the error ? I started an equivalent thread in another physics forum but nobody understand. I hope my english is clear enough for understand the problem. The system is under gravity and everywhere outside...

Homework Statement Helium in an ideal Diesel cycle is compressed from 4 L to 0.25 L, and then it expands during the constant pressure heat addition process to 0.50 L. Under air standard conditions, the thermal efficiency of this cycle is: a) 79.5% b) 20.5% c) 61.4% d) 67.4% e) 84.3%...

Homework Statement "A car has a six-cylinder Otto-cycle engine with compression ratio r = 10.6. The diameter of each cylinder is 82.5 mm. The distance that the piston moves during the compression stroke (see fig. 1) is 86.4 mm. The initial pressure of the air-fuel mixture (at point a in...

Homework Statement Construct a Microsoft Excel® spreadsheet that models an internal combustion engine based on the ideal air-standard Diesel cycle. Given the minimum temperature (##T_1##) and pressure (##P_1##) in the cycle, the engine size (##V_1##), the compression ratio (##r_v##), the...

The question is: Consider a thermal battery - a device for storing mechanical energy. Use two large containers as heat reservoirs where one contains ice and water in equilibrium and the other contains steam and water in equilibrium. Both are held at pressure=1atm. Energy is stored by using a...

I'm having some difficulty understanding how to find the work and heat transferred in a carnot cycle. Problem: One mole of ideal gas (cV=1.5 R) perform a Carnot cycle between the temperature 400 K and 300 K. On the upper isothermal transformation, the initial volume is 1 liter and the final...

Homework Statement For the counter shown below, determine the main cycle, and for each of the unused states, show what happens if it starts up there. http://i45.tinypic.com/33l1lhc.jpg Relevant equations N/AThe attempt at a solution Based on the diagram in the link I provided, I know that...

In an adiabatic compression/expansion cycle of an ideal gas, does the temperature return to its initial value after the cycle has completed? Or does it increase as the cycles continue?

On what factors does the pressure in condenser of a rankine cycle depend? The lesser the pressure in the condenser, the more expansion work will be done by the steam turbine. And depending on the pressure in the condenser, the temperature of the steam entering the condenser will depend...

This is a very important question for me which has bothered me greatly. I started talking about it in the Smolin cosmic natural selection thread. What I would like to know is, if the Universe started over a very large number of times (n) from t=0, the start of the big bang, In how many of these...

hello, new to site. This is my first post. I just was wondering what any ones thoughts were on using the carbon, nitrogen, oxygen cycle in a dense plasma focus device to produce aneutronic fusion power.

Dear experts, please help me with this debate between my buddy and I. I'm on the side that most mammals, like cats, dogs, humans and monkeys have 2 stage life cycle. Young --> adult and back. My buddy says it should be 3 stage egg--> young--> adult and back. We are both rather weak on...

hello all I want to find costs of some components of a combined cycle power plants.like turbine.generator and ... how can I find them?

hello all I have a project about a combined cycle power plant costs from first to the end of the project. I just need the prices of componets of it. I need a guide to find them.

Hi all. I'm trying to find a durable elastic material for a project of mine but I can't seem to find the needed information. Basicly what I need is a elastic/rubber band that can withstand at least 100 000 (or preferably over 1 million) stretch cycles without its resting length increasing more...

Hello everyone, I'm trying to find the times when one cycle occurs for a FM wave. For instance, given y(t) = sin(2∏f_{c}*t_{1} + sin(2∏f_{m}*t_{1})) at an arbitrary time t_{1}, I wish to find the time t_{2} such that (f_{c}* t_{2} + sin(2∏f_{m}* t_{2}) – (f_{c}*t_{1} +...

Homework Statement The question is pretty much explained in the picture. The area ABCD is enclosed, i need to find that area. The equation for AB is P=0.8+8.6e^(-0.3V) and the equation for CD is P=1.2+9.6e^-(0.1V) What I did was find the area enclosed by the rectangular shape (C-B)*9. From...

Hello, I'm working on a small scale parabolic trough concentrator project to generate electricity. This electricity is used for pumping water for irrigation,and I want to use an open loop Rankine cycle with no condenser(if it is applicable),to reduce cost,with the steam exhausting directly...

Hello everyone, This is my first post on PhysicsForums (although not my first encounter) which I would like to start with asking a question. How does heat from the sun get distributed on Earth so that we have temperature variations between day and night? In other words, if an...

[b] My attempt [b] Q Reaction 1: Q1 = 2(1.007825) - (2.014102 + 0.000549) = 9.99E-4 u Q Reaction 2: Q2 = 1.007825 + 2.014102 - 4.002603 = -0.980676 u Q Reaction 3: Q3 = 3.016030 - (4.002603 + 2(1.007825)) = 0.013807 u --------- 2(Q1) + 2(Q2) + Q3 = -1.945547 u (-1.945547...

Homework Statement Derive a formula for the efficiency of the Diesel cycle, in terms of the compression ratio V1/V2 Homework Equations e=\frac{W}{Q_{h}} w= ∫pdV The Attempt at a Solution Now I know I should have used e=1-\frac{Q_{c}}{Q_{h}} to get it but he said it is...

Hello, In the Volume vs. pressure graph I understand the area under the curve is work. However, I have a hard time reconciling this graph with a pressure vs. temperature or a temperature vs. volume graph. What does the area inside the box represent? Work? Like which parts on the P vs. V graph...

http://www1.gantep.edu.tr/~physics/media/kunena/attachments/382/chapter2.pdf On page 9 and 10 of the above PDF the method for deriving the fractional energy loss per cycle in a lightly damped oscillator is described. I understand and follow this derivation. What would the derivation...

Hello, In http://www.aerostudents.com/files/gasTurbines/gasTurbinesFullVersion.pdf it is shown that the efficiency of a gas turbine is determined by the Brayton cycle and it depends on the pressure ratio ε. ε is the compression ratio before fossil fuel burning invests further energy into...

Hi, For my Bachelor's thesis I've been working on a finite time Carnot cycle. I've finished my numerical analysis using the differential equations governing the time evolution. My next step should be a simulation. First I should stick to a 1 dimensional system. This system consists of a...

Hallo, I read about thr Carnot-Cycle and got a problem. A->B: isothermal B->C: adiabatic C->D: isothermal D->A: adiabatic I want to understand how to calculate the work done in the isothermal processes. I have read: W_{AB}= T_{H}Nk\ln{(\frac{V_{A}}{V_{\text{B}}})}\\...

Two questions: 1. What does the T-s diagram look like for the irreversible cycle? 2. Do the isentropic efficiency equations that you apply to turbines and compressors (especially in the Rankine cycle) apply to the theoretical "turbines" and "pumps" in the Carnot cycle?

Hey, I wanted to generate a pulse of ON time of about 10-50 ns and time period of around 1us. Don't know how to get such precision ? Thanks

Homework Statement Consider the gas do the themodynamics process. If the process graph is one line with constant gradient, Homework Equations What process was happened? How to calculate its amount of heat which absorbed or liberated? The Attempt at a Solution I really need your...

Homework Statement A conventional vapor-compression refrigeration cycle uses ammonia as the refrigerant. Evaporation and condensation are at -4°C and 34°C respectively and the refrigeration rate is 5kW. The compressor efficiency is 0.75. Assume that the throttle process is isenthalpic...

In an liquid fluoride thorium reactor, how is the reaction started? My assumption would be a piece of fissile material would be somehow inserted into the fuel to introduce neutrons to the solution, but I have not found any information to show if this is how the reaction is started. If this is...

Hello ,everybody I plan to develop a nuclear fuel cycle simulation software . Is there any body interesting it. I think this is a very complex project. :)

For convenience, let's assume the following process to be ideal. Process 1-2 Isenthalpic compression Process 2-3 Condensation Process 3-4 Throttling Process 4-1 Evaporation The refrigerant is dry-saturated at the end of compression. Here's what I don't understand: During process 2-3, if we...

I have always been wondering how in an active star the H/He fusion cycle is "managed" for lack of a better word, a little like a logistical analogy really. Specifically: i) Where in the star is the yet-to-be-fused H 'stored'? ii) Where in the star is the He result of fusion 'stored'...

Hello, I have seen graphs of Battery's DoD (depth of discharge) vs Life Cycles. But at the same time, "life cycle" is defined as the no. of COMPLETE charge-discharge cycles that a battery can perform before its nominal capacity falls below 80% of its initial rated capacity. Here's the...

Homework Statement Consider the following reversible cycle: Where S2=S3=(S1+S4)/2 . Prove that the efficiency η is: η= 1 - 2*T6 / (T1+T3) Homework Equations The Attempt at a Solution I know that in a T-S diagram the heat received by the system is equal to the area...

Homework Statement Compute the efficiency of the following cycle: Homework Equations The Attempt at a Solution I know there's an isothermic process between a and b, where heat comes into the system, let's call it Qh. I also know that between b and c heat will leave the...

I am attempting to improve a spreadsheet I created back in uni some 5-6 years ago, which models all the velocities and accelerations of the pistons and rods, as well calculating pressure, temperature and resulting torque. It is only a simple model so far, originally it started simply by...

Homework Statement The problem and its solution are attached as TheProblemAndSolution.png. Homework Equations Integration P = VI V = RI The Attempt at a Solution I think Wolfram Alpha “says” ( http://www.wolframalpha.com/input/?i=integrate+900sin%5E2%28377t%29+dt+from+0+to+pi ) that...

I'm trying to find why this thermodynamics cycle is not possible but I don't find. The only problem for me is at step 3, the gas can't become a liquid but why ?

$$ \begin{cases} x'=.05\left[y-\left(\frac{1}{3}x^3 - x\right)\right]\\ y'=-\frac{1}{.05}x \end{cases} $$ So this a Van de Pol equation where $\mu = .05$. It is basically a circle at the origin with radius 2. How do I find the period?

s = NDSolve[{x'[t] == \[Mu]*(y[t] - (1/3*x[t]^3 - x[t])), y'[t] == -1/\[Mu]*x[t], x[0] == 8, y[0] == 2}, {x, y}, {t, 150}]; This code will show limit cycles when you parametric plot the Van de Pol Equation. However, I want to find the period T numerically. I need to add in a piece for mu...

So I get that when the VP is equal to atmospheric pressure of 14.7 psia, if you will be at a saturated liquid and when more heat is added, it is latent head changing it to a gas. If however you are at a closed container where the can physically alter the "atmospheric pressure" in the container...

Homework Statement How many elements of each cycle-type are there in S5? The Attempt at a Solution One way of working this out would be to write out each permutation and see how many 2-cycles, 3-cycles ,4-cycles and 5-cycles there are but given that there are 5! permutations this would...

Homework Statement For the counter shown below, determine the main cycle, and for each of the unused states, show what happens if it starts up there. http://i45.tinypic.com/33l1lhc.jpg Homework Equations N/A The Attempt at a Solution I thought I knew how to do this, but after some...

I'm trying to control the speed of a computer fan using the radio input from an RC transmitter/ reciever. The PWM output of the reciever is 1ms to 2ms high and 20ms low, so 10%-20% duty cycle. The computer fan requires a 30% to 100% duty cycle, at 25khz (about a 40uS pulse) I was thinking of...

Question is attached Thanks!

Would someone be able to help me with the question Life cycle of butterfly is egg -> caterpillar -> butterfly. Each week 5% of the eggs will hatch and 2% of the caterpillars will turn to butterflies. You start with 100 eggs and 60 caterpillars. Using calculus to obtain an equation...

Homework Statement A heat engine operating between freezing and boling points of water takes 20 cycles to raise a mass of 1000kg through a height of 3m. Calculate the minimum energy per cycle that must be extracted from the hot reservoir in order to achieve this. Homework Equations...