Cycle Definition and 617 Threads

Homework Statement Hi, I'm a new user and got this problem. Sorry to bother, but I couldn't find any relevant information from my Physics books.. The problem states: Build a heat engine using these processes: adiabatic, isothermal, isochoric and isothermal. The work-cycle of the engine must...

Hi! For our class project, we have to design a system that freezes an amount of water as quick as possible. The refrigerant is R134a. The compressor is known. I don't really know how to get started here. How do I choose the evaporator pressure and the superheating, and equally the condensor...

Homework Statement The last part of my question reads: Give the equations you would use to determine reactor thermal output if the plant is to produce 1000 MWe. All expressions for work and heat transfer rate should be expressed in terms of the appropriate mass flow rate ratios. Homework...

I have a heat exchanger with water/air as medium and we test it in a facility where we cycle the water temperature between 25 to 95 degrees Celcius with a cycle time of 5 minutes for thermal fatigue. Our customer require the testing to be between 5 to 95 degrees instead with 3 minute long...

hi , will change first law efficiency proportional to second law efficiency? for example in gas turbine cycle, how change? other equation: hi , will change first law efficiency proportional to second law efficiency? for example in gas turbine cycle, how change? other equation: How is the...

So I have been thinking about the photon gas, and I have read several papers talking about how a Carnot cycle could be created for it. This is fantastic, and it is something I am quite comfortable with. All of the papers present the P-V diagram as the "golden" Carnot cycle for the photon gas...

A basic instruction cycle consists of these 5 stages. 1. IF - Instruction Fetch 2. RD - Instruction Decode and Register Read 3. EX - Execute 4. MA - Memory Access 5. WB - Write Back I understood the meaning of all the stages accept 4th MA (Memory access), what's the significance of this stage.

hi friends, I am working EES software for thermodynamic lesson,I am analyzing second law efficiency(exergy efficiency) and exergy analysis for all components of gas turbine cycle. Now I have a problem,exergy efficiency of turbine decrease with increasing before temperature,why? As you know...

Homework Statement Hi Guys, I did a heat engine experiment where we put a weight on a piston and moved an air cylinder in a hot water bath, then removed the weight and but the air cylinder in a cold water bath to make a heat engine cycle. I am just wondering in the simple heat engine which...

Homework Statement A heat engine containing an ideal gas has a reversible cycle which consists of 2 constant volume segments with V = 1ℓ and V = 3ℓ and two constant pressure segments with P = 1 atm and P = 2 atm (see figure below). The temperature at point “c” is Tc = 273 K. A) Is the path...

i know that regeneration is heating the feed water by the bled steam from the turbine to reduce the sensible heat addition by the boiler but doesn't that also causes a reduction in the steam turbine work because we've taken some steam from it . can anyone explain please i'may have some...

Homework Statement Let ##g \in S_n## and suppose that we know the cycle notation for ##g##. How can one compute its order without repeatedly composing ##g## with itself? Homework EquationsThe Attempt at a Solution [/B] I took the group ##S_4## and tried formulating a conjecture. I composed...

The last reaction in CNO-I sees 15N + 1H --> 12C + 4He I'm interested why it doesn't produce 16O, which is also stable.

Homework Statement A Rankine cycle with reheat uses water as its working fluid. Superheated vapour enters the high-pressure turbine at 10 MPa and 440oC. The steam expands through this high-pressure turbine to 0.7 MPa and is then reheated to 400oC. The steam then expands through the low-pressure...

Homework Statement I understand the rest of the cycle, the way my textbook has it, which is: 12C→13N→13C→14N→15O→15N→12C+4He The portion in bold is what I don't understand. Homework EquationsThe Attempt at a Solution I do understand that when the mass number increases (like from Carbon-13 to...

Homework Statement During one complete cycle, a wave moves through ___ wavelength, ___ period, __ amplitudes Homework EquationsThe Attempt at a Solution Well I got 1 wavelength, 1 period, and 2 amplitudes But apparently the answer is 1 wavelength, 1 period, and 4 amplitudes But I don't see...

Hello everyone, The problem I am working on asks me to write a Cayley table for ##D_3## using cycle notation. However, I am having difficult with determining how to operate on a pair of "cycles." Here is my work so far: ##R_0 = e = ()## ##R_{120} = (123)## ##R_{240} = (312)## ##F_T =...

Assumption: -there is no serious astronomical phenomena determining that - either the planet is tidally locked, has too long day cycle, or is too far away from its star and inside bases anyway humans rely on artificial light; -there is a colony of a size of at least medium city; -post scarcity...

hi all. just to give you a background story - i am graduate student at U of Calgary in the ECE department. My colleague, from the Mechanical department did not show up yet, because of which I have to work alone on my project, including the mechanical part at which i am no expert but have some...

Wiki claims in stars, heavier than 1.3 solar masses (where CNO plays major role) there is an inner convection zone near the core, but no outer convection zone. Hence, such stars should be "calmer" - no solar flares, less radiation... Am I right?

What is current state of the solar cycle?

Homework Statement I have been given a description of a thermodynamic cycle that looks like this. I have two polytropic processes (n1=1.2, n2=1.9), and one isochoric. The known data are: p1 = 1 bar T1 = 15 °C p2 = 15 bar Homework Equations p v^(1.2) = 0.7958 p v^(1.9) = 0.69657 The Attempt...

Homework Statement 2. The attempt at a solution Is it only possible when 600J of heat is exhausted and 400J of heat is converted into work? Is the 600J heat will enter the cold reservoir and available to do work again? q1/T hot + q3 / T cold = 0 q3 = 600 when T = 300K

Greetings, Here is my thought process on the carnot cycle, regarding heat pumps and engines. I'd much appreciate it if you can clear up any misconceptions and answer my question at the very end. So my book states that there is no change in internal energy in a heat engine, but neither confirm...

I understand that you need certain work for the refrigerator to work, and that it comes from the compressor. Why isn't a pump used instead? Why do you have to compress and heat the air so much? Thank you

Please help me with this, In Reheat Rankine cycle, we first Expand the steam partially in a high pressure turbine and then reheat it again . How is this partial expansion in high pressure turbine done ? in the sense, what is the procedure followed to have only partial expansion of steam...

Do white dwarf planets ever die and eventually there will be no remains of the sun? What will happen to the gas giants with no sun to orbit?

When Stiochiometrically correct mixture(equivalence ratio=1) is burned in air fuel cycle some of the air is still left after point 3 in P-V diagram...Theoretically the whole fuel and air should combust till point 3..Then why is some air left out there.And thus the max temp is when mixture is 6%...

I am having a real tough time determining the torque required to power an electric motor used to drive a cycle. I have calculated the Torque as: Torque = μ X mg X r(radius of the wheel) Now I am confused as what is μ. I know it's the coefficient of friction but, not sure whether I have...

I have a project which is to create a mechanical device that would transfer close to 1 J of energy from one form to another and must be able to show how you calculated the 2 energy individualy and show that the energy loss between the 2 is within a % difference. I posted on here yesterday...

Homework Statement The temperature in a refrigerator evaporator coil is -6oC and that in the condenser coil is 22oC. Assuming that the machine operates on the reversed Carnot cycle, calculate the COPref , the refrigerant effect per kW of input work, and the heat rejected to the condenser...

Homework Statement Let the radiant energy in a cylinder be carried through a Carnot cycle. The cycle consists of an isothermal expansion at temperature T, an infinitesimal adiabatic expansion where the temperature drops to T-dT, ad returning to the original state via an isothermal compression...

Homework Statement See attachment Im struggling with b and c. I did an attempt, but really don't know if it is correct. Homework Equations The Attempt at a Solution See attachment

Year 0 in some systems exists and in year 0 there is a blue moon. There are also blue moons in year 3, year 8 etc. This 4,5 I have seen so far and this timeanddate.com makes me think that it has that 4,5,3,16,17,2,9, and then repeats at 16 cycle. Sites including wikipedia say that a blue moon...

hi guys , I am studying thermodynamic cycles in my thermodynamic course , I have a question about the power cycles like Rankine , in these systems v use superheated steam to produce work from turbine, so y there must be condenser to cool it first and then heat it , y can't v use turbine - boiler...

Homework Statement A certain fluid of mass 1kg undergoes a cycle of processes in a piston and cylinder device as follows: Process A-B: 70kJ of work done on the fluid. 35kJ of heat rejected to surroundings Process B-C: 50kJ of heat transferred to the fluid. No change in internal energy of...

Why does heat addition happen at constant pressure in diesel cycle ? what is the basic concept behind it?? please do enlighten me on this topic. thanks in advance

I've carried out some testing on a PWM controller using a 555 timer IC (see attached for circuit diagram) and I am having a little trouble understanding the results. When the POT resistance is increased the duty cycle decreases. As I understand it, when the resistance is increased the voltage...

Homework Statement Homework Equations The Attempt at a Solution I can do everything else except work for part one going from A to B. What I did was -∫PdV = -nRT ∫(1/v)dV = -nRT ln (Vf/Vi) I can solve for T because everything is given, T in Kelvin is 882. From PV=nRT T=(5atm)(10L)/1mol*R...

Homework Statement An ideal gas is taken through a Carnot cycle. The isothermal expansion occurs at 250°C, and the isothermal compression takes place at 50.0°C. The gas takes in 1 200 J of energy from the hot reservoir during the isothermal expansion. Find (a) the energy expelled to the cold...

What happens in a reversed carnot cycle? I mean in refrigerators.The gas is adiabatically compressed so that it's temperature rises.Then it is isothermally compressed so that the heat is rejected to the sink.But then why it is said everywhere that the working substance absorbs heat from sink...

Hi, In what cases do I neglect the work done by the pump in an actual rankine cycle? I am reading that h5-h4 is negligible but in what circumstances do I accept this. Is this only for ideal rankine cycles? As I understand thermal efficiency is (work out + work in)/Heat in Thanks

Hey I am new to this forum and I am looking for any pointers about my ORC before I start it up? I made an ORC in my garage with two Swep heat ex-changers, one B35 and one B10 (used but flushed). I have hooked up 3 (used) hot water heaters to the B35, 40 gal each with 4.4 kW elements in them, for...

Greetings, While attempting to learn something about cryptography, I have repeatedly encountered a commonly quoted argument about the minimum energy required to cycle a 256 bit counter through all its states. It says that the absolute minimum energy required to change the state of a bit is...

Calculating the Efficiency of A Rankine Cycle For Various Parameters Homework Statement Calculate the efficiency of a Rankine cycle that is modified from the parameters used in the text in each of the following three ways (one at a time), and comment briefly on the on the results: (a) reduce...

Homework Statement Basically I have the following problem. Given the equation of state \sigma = \frac{b}{T}\frac{L - L_0}{L_0} where b and L_0 are positive constants, calculate the work done over a Carnot cycle by a wire with this equation of state.Homework EquationsI already have the work...

Homework Statement The Clapeyron cycle efficiency is similar to the Carnot cycle except that two adiabatic paths are replaced with isobaric processes a) based on the above information, draw a Clapeyron cycle. b)Derive the efficiency of the reversible Clapeyron cycle Homework...

Hi all, for job reasons I have come across LCCA, and I have started documenting myself reading this ebook that I found googling: Fuller-Petersen, LCCA. Now, I'm new to the topic, and I have a few questions: 1) Is it just about calculating all the costs of two projects, maybe taking inflation...

Homework Statement n = 5 moles, monatomic, ideal gas p1 = 7280 Pa; v1 = 2 m3 p2 = 7280; v2 = 6 p3 = 6500; v3 = 6 What is the change in heat, from 2 to 3, and from 3 to 1? Homework Equations PV = nRT U = (3/2)nRT Q = du + dw The Attempt at a Solution PV = nRT (7280)(2) =...

Homework Statement In the thermodynamic cycle as shown, a) What is the direction that the cycle is executed-clockwise or anticlockwise? b) What is the work done? Homework Equations First law of thermodynamics for a cycle E2-E1= Q-W= Tds-Pdv=0 The Attempt at a Solution a) I...