Engine Definition and 999 Threads

1. Thot reservoir= 600K, Tcold reservoir= 300K, Output= 0.5 J of work for every J of thermal energy extracted from the hot reservoir. What is Qh? 2. efficiency= W/Qh; Carnot efficiency= 1- (Tcold/Thot); 3. I have found the Carnot efficiency to be 0.50. I don't know where to go...

Homework Statement I'm taking a practice test and I need some help with a heat engine problem. There are three parts, the one that's giving me trouble is a-->b. The Volume v. Pressure graph shows a straight line. Pa= 5 atm Va= 5 L Ta=300K and Tb=800K are given. So pressure is decreaseing...

Is this gas turbine engine compressor discharge air temperature calculation relatively accurate? Problem: Calculate the compressor discharge air temperature in ºF of the following gas turbine engine compressor core specifications. Gas Turbine Engine Compressor Core Specifications...

I have a motorcycle engine on a test stand and I need a way to measure the mass flow rate into the engine. It is currently carburated. I had two ideas off the top of my head. 1) build a venturi, and measure the pressure drop to figure out the velocity and therefore the mass flow rate...

Homework Statement A heat engine uses the closed cycle shown in the diagram below. (Figure 1) The working substance is n moles of monatomic ideal gas. Find the efficiency of such a cycle. Use the values for pressure and volume shown in the diagram, and assume that the process between points...

The problem: An engine puts an ideal monatomic gas through a clockwise rectangular cycle on a PV diagram with horizontal and vertical sides. The lower left point has a pressure of 1 atm and a volume of 1m^3 and the upper right point has pressure and volume three times greater. Calculate the...

Homework Statement I am only confused about question 2. The Attempt at a Solution I decided to use bernoulli's equation to find velocity at point 1. With velocity at point 1 and point 2 I can use conservation of momentum to solve for the force exerted. In this case there would be Fx...

Thomas the tank engine and Diesel are involved in an elastic collision. A 2.5 kg Thomas is at rest but is approached head-on by a 5.0 kg Diesel moving at 0.60 m/s. The force-separation graph for the ensuing collision is given. FYI I am terrible with graphs, IDK WHY.. :frown: mT =...

With four Rolls-Royce Turbojet engines attached on A380, I wonder, if the optimization of fuel efficiency as its prime design factor/variable? If so, may I know, what it is air by pass ratio?

The 6575-lb engine is suspended from the crane boom. Assume the initial weight of members CD and AB to be 10lb/ft and 50lb/ft. Determine the resultant internal loadings acting on the cross section of the boom at point E. Also, find the joint reactions at A, C and D. So far I solve for the...

Homework Statement An electric generating station is designed to have an electric output power of 1.4 MW using a turbine with two-thirds efficiency of a Carnot engine. The Exhaust energy is transferred by heat to a cooling tower at 110°C. a) Find the rate at which the station exhausts energy...

criteria to find oil pump capacity for engine , do anyone knows for diesel engine 3lits.

Basically, my understanding is that every satellite that is not at a lagrange point will see its orbit eventually decay and it will crash back into the earth. Could an ion engine be set to fire at certain times to offset this? Because the rate of decay is slow, an ion engine might be up for it...

Does a stronger engine need a higher viscosity fluid? What's the reasoning behind this?

When the F-35 is taking off or landing vertically, are any of the jet exhausts supersonic? I have seen the amount of thrust they produce but nothing about the Mach number. I am not looking for anything specific just whether or not the exhausts are supersonic.

Stirling engine: the cycle is composed by two isothermals and 2 isometrica and there are just two heat reservoirs. By the isometrics I would say that that it is irreversible since you exchanging heat with a reservoir at a different temperature than your gas. However my notes say the...

An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +38 ft/s2. After some time t1, the rocket engine is shut down and the sled moves with constant velocity v for a time t2. Assume the total distance traveled by the sled is 15750 ft and the total time...

I was stopped at a red light and there was some smoke coming out of the engine compartment of my car. There is also a slight burning smell. This is definitely not good. If you are a mechanic or automotive engineer, what is your take on this?

Hi, I have a problem with measuring cooling performance of a car on a chassis dynamometer. But maybe I should start with the theoretical part of my problem, namely with the dimensional analysis. If I have a physical system and I am interested in finding one variable as a function of all other...

Ok, so I have complete faith in the tried and proven laws of thermodynamics, including the part of the second law which states that it is impossible to create a heat engine working in cycle that takes in a certain amount of heat energy, and converts all the heat energy it takes in, into...

Hey guys. I am new to engineering and I came to this because I wanted to make my own miniature jet engine. I have a limited knowledge of physics but I wish to broaden it through this idea. Now I know that this was made before for RC models, but I want to actually make one so I understand how...

Hello, my question is about air in engine cooling systems. Coolant is formulated to resist boiling, and furthermore kept under pressure to increase its boiling point. I think this is to control its phase. In other words we must prevent coolant from boiling (vaporizing) because vapor does...

Jetpack International's T-73 achieves vertical takeoff with an actual jet engine as opposed to the rocket engines used by the majority of jetpack models. This allows it to have longer flight time (9 minutes as opposed to 30 seconds). Some fighter planes also manage VTOL with a jet engine, the...

This is all in relation to a 90 degree v8 I am looking for the highest frequency/note/tone/pitch I can get. I very much enjoy the higher, crisper, cleaner sound the european v8 makes. I hate with a passion the rumble of the harley/dumptruck American v8. I have heard flowmasters on these cars. I...

Is making photon Engine possible ? :A different thought to power space craft! Now a days Scientists are working on photon engine. They are trying to power engine from light. Thought is looks great but there is practical engineering problems with it. Ya it is true that photons have momentum...

http://en.wikipedia.org/wiki/Heat_engine This is one of those threads where the OP proposed a device which will not work and hopefully by the end understands why. So here's the device... Air enters through a long intake tube. At the end of the tube it enters a combustion chamber where fuel is...

Hi all, I am trying to compare the heat input into an engine with useful work out. I have taken a measurement for Torque, and have calculated heat input per cylinder based on combustion calculations i.e throttle % x cal value of fuel x fuel mass. I am happy with the heat input...

Hello again, I am currently designing a flywheel for a 745 KW engine inertia dyno. Basically my design requirements are so: Max RPM: 530 RPM (=55.5 rad/s) Flywheel Diameter: 1.7 meters Time needed to accelerate: 60 second (to max rpm) I need help determining the mass of the...

Homework Statement A nuclear power plant generates 2000 MW of heat energy from nuclear reactions in the reactor's core. This energy is used to boil water and produce high-pressure steam at 300° C. The steam spins a turbine, which produces 700 MW of electric power, then the steam is condensed...

Aloha, This is my first post, I am happy to be here. Would there be any advantage to a internal combustion engine(ICE) that fired two pistons simultaneously? This would be an alternate-firing ICE that would fire the pistons in pairs every 180º, instead of one piston fire and the other...

Mutations: evolution’s engine becomes evolution’s end!? Did scientist Alex Williams really disprove evolution? is he right ? is there a reply to his topic ? i need to understand how does this make mutations evolution’s end ! Mutations: evolution’s engine becomes evolution’s end! by Alex...

Hey guys. As the title reads, I am a part of a research project and we will soon be testing a 100lbf jet engine. We take safety very seriously and want to take all the proper precautions in order to ensure everybody involved will come out of the experimentafely in case something goes wrong...

Just wondering what the name of the component as a whole is? And what is it made of? Also, if you could tell me the name of all the constituent parts, that would be great...

Hi, new to the forum, it is a really spiffy place. I'm not really much of a programmer, but I have an interest in it and kind of like to piddle around with programming. I am learning C and C++ mostly by doing, browsing books, and asking dumb questions of people who know a lot more about it than...

Stirling engines use regenerators(heat pumps) to recover heat and increase their efficiency.The basic problem here is "The regenerator constitutes a (dead) volume which thwarts the benefit of its presence.There is never absolute truth" I believe I have a working concept of the heat pipe.My idea...

why cannot hydrogen and oxygen not used in internal combution engine as fuel? it would be pollution free.

Hi for a bit of work I have to explain the advantages and disadvantages of a higher engine intake air temperature. I have been told that it decreases the power output of the engine but I can't seem to work out why it would decrease. I also want to comment on how it affects the efficiency but...

My problem only gives me joules to work with. Is it possible to convert from joules of energy to temperature (Kelvin)?? If so how?

Homework Statement An inventor claims to have developed an engine which takes in 1.1x108J of heat energy at 400K, and rejects 5.0x107J of heat energy at 200K. Would you advise investing in this project? Explain your answer. Homework Equations W = Q1 – Q2 η = W/Q1 = 1 – Q2/Q1 The...

i was admiring its animation like when this popped into my head. any answers? also anybody know any latest developments in lubricating closed off engines?

Hello Gentlemen, Do you help me in finding flow rate calculation for diesel engine oil pump? Is anyone know procedure need follow based nominal clearance / maximum clearance? How we can find flow rate requirement for engine.

Homework Statement Taken from adkins Introduction to thermal physics A reversible heat engine is operated between two bodies, one of heat capacity C1 initially at temperature T1 and the other of heat capacity C2 initially at temperature T2. As the engine operates, the warmer body gradually...

This guy ran over his own engine block after it completely exploded during a tractor pull. I have been a life-long fan of motorsports and I've never heard of this happening before. Must be a world's first.

Hello, I am having difficulty understanding the paragraph in my textbook explaining why no other engine can be more efficient than a carnot engine. What does it mean? To prove the validity of this theorem, imagine two heat engines operating between the same energy reservoirs. One is a Carnot...

Homework Statement A hypothetical engine, with an ideal gas as the working substance, operates in the cycle shown in the diagram, show the efficiency of an engine is : n= 1 - 1/\gamma ((1-(P3\P1))/(1-(V3/V1))) The diagram is basically a section the bottom left quadrant of a circle with an...

Just a simple question of what the ideal torque/engine speed graph would like? Also, could anyone direct me to a good website or book that would help me understand the following things better: tyre slip/traction control gear ratios and how they affect acceleration

Homework Statement The Diesel cycle is an idealized representation of the process that occurs in a Diesel combustion engine, as shown in the graph below. Starting at point a, the Diesel cycle consists of an adiabatic compression, an isobaric expansion, and adiabatic expansion and an isochoric...

The burned gases of a rocket engine are ejected from the rocket nozzle at a speed of 17,000 ft/sec. If the weight of gas ejected is one pound per second, find the thrust developed by the rocket. I don't really have an equation to use here but my guess is F = M\32.2 * Ejection Velocity...

Allegedly, this video is a test demo of the physics and vehicle damage engine that will be included in the upcoming video game Grand Theft Auto 5. I'm not sure if this a hoax or if it's the real deal. If it's true then we will finally have some breathtakingly realistic crashes. Although...

Homework Statement It's basically the classic problem I've seen here a lot. There are two bodies, both with equal heat capacity (C_P), one at temperature T_1 and the other at T_2. They exchange heat using an infinitesimal-reversible Carnot Engine, which will work until thermal equilibrium is...