Engine Definition and 999 Threads

I have an spark ignited 4 cylinder 2000 cc engine in a wagon and I think its 50% thermally efficient at idle due to the mods I have done on the intake manifold. My engine uses (mesured on video) roughly 9.807 cc/min at approx 750 rpm and the only reference I have come across is a similar...

I think it is due to friction and the carnot efficiency is derived in a reversible cycle. Also,can i build just a little bit irreversible but still carnot? But if irreversible how can i draw the graph? Still smooth line?

hey guys, We have a design project where we are supposed to design something cool to machine and later auction it off. My group has already come up with a plan to build a small stirling engine. I've been thinking if there could be anything we can add on to it, like a useful/fun addon...

Homework Statement A Carnot heat engine operates between temperatures Th and Tc. (a) If Th = 515 K and Tc = 363 K, what is the efficiency of the engine? 0.30 Your answer is correct. (b) What is the change in its efficiency for each degree of increase in Th above 515 K? ? K-1 (c) What...

Hello all. I've been wanting to build a Stirling engine at home out of parts that i could easily afford/scrounge up. Not one of those small ones that you hold in your hand, but one that could generate some real work. Enough to run a small generator maybe. The problem is that i have absolutely no...

Hello, For a reversible heat engine between temperatures T_1 and T_2, the ratio of heat going in and out the engine is \frac{Q_1}{Q_2} = \frac{T_1}{T_2} (second law). Say T_1 = 200 K and T_2 = 273 K, then heat goes from 2 to 1 and as we can see, the ratio of heat that goes in the engine is...

one problem, the website is down, and has been for quite some time now. lots of info on the site great candidate for a high efficiency diesel engine.

I wanted to ask about plasma propulsion engine. Plasma can be made by using radio waves. How this part of device looks like?(I know something, like an antenna, is used) I searched the net, but I didn't find anything. Thanks in advance. P.S Please explain as simple as you can

In several textbooks I've read that treat classical thermodynamics, there is a theorem due to Carnot that is commonly stated: "No engine operating between two given temperatures is more efficient than a Carnot engine" (incidentally, this is the statement in Huang's book) In these same...

I've never taken physics, and I'm not even sure this is physics. :S On the hint it mentions, think of freshmen physics, but I honestly have no clue. Could someone help me out on how to even start this problem? Estimate the weight savings if a typical automobile engine (100 kg) is made of...

Homework Statement A rocket is launched at an angle of 53 above the horizontal with an initial speed of 100 m/s. It moves along its initial line of motion with an acceleration of 30 m/s^2 for 3 s. A this time its engines fail and the rocket proceeds to move as a free body. a. Find maximum...

I wanted to get some opinions on this, I am serious considering designing a ramjet rocket hybrid engine for my 3rd year mechanical engineering degree project and have started doing the research to see exactly how much work it entails I still can't quite decide... is this a realistic project? (my...

From a chemical point of view, what are some of your thoughts about powdered graphite in engine oil? I think it would work very well because it would suspend particles between the graphene sheets.

Homework Statement A 1600kg jet engine is fastened to the fuselage of a passenger jet by just three bolts (this is the usual practice). Assume that each bolt supports one-third of the load. (b) During flight, the plane encounters turbulence, which suddenly imparts an upward vertical...

I posted this on another section, but got no replies in three days...so thought maybe I'd had posted in the wrong section...apologies. I have an idea pertaining to energy storage in flywheels, something like they do in the KERS, and need assistance here... Ok, my idea involves using a...

Homework Statement A Carnot engine performs work at the rate of 360 kW while using 720 kcal of heat per second.If the temperature of the heat source is 650 C, at what temperature is the waste heat exhausted? Homework Equations because Th,Qh,and W are given so i going to use this formula...

Homework Statement During the working cycle of an engine, the heat transferred out of the system was 200kj/kg of working fluid. The internal energy also decreased by 300kj/kg of working fluid. find teh work done and state whether it is work done on the engine or by the engine. Homework...

Hi Guys I m trying to make a Stirling engine power by solar heat. Somewhere I found out that the solar flux available on Earth is abt 1350watts/m2 Is this heat energy only or "heat & light " combined?? I m trying to find out if my soar engine will be better than traditional solar...

what is an implosion engine?

I have a qualitative understanding of a heat engine; that being that when heat moves through a heat engine from a source to a sink, an amount of energy that passes through the heat engine will be absorbed, until no heat gradient exists between the source and the sink The attachment is a...

How to choose thermodynamic cycle for designing new jet engine? While designing new jet engine what parameters are important for choosing thermodynamic cycle? what other parameters are important for jet engine designing?

Recently there was information that military is developing a nutating disk engine http://en.wikipedia.org/wiki/Nutating_disc_engine" which, as they hope, will have higher power density, than reciprocating engine.Also some people say,that this is low friction design. Does anyone know what is...

Is there a way to figure out the horsepower of an electric motor if you know the horsepower of a gas engine. For example: If the torque-to-horsepower equation goes as follows: [(Torque x Engine speed) / 5,252 = Horsepower] and I know that a 161cc gas engine has a Gross Torque of 7.00 ft-lbs...

So with most of the hybrid vehicles around, they use a conventional engine and transmission with an electric motor to take over at certain points, and the engine recharges the electric motor. But could a hybrid be made that uses say an ordianry gasoline or diesel engine that directly powers an...

How the specification of an engine power done. Why its said power and torque max at some speeds. I am searching for the answer for a long time. Can someone help me..

A pulse jet has only one moving part. Nice. But what if it didn't need any moving parts? Stupid idea, right? Check out this stupid idea. They're all over the internet. http://www.youtube.com/watch?v=5U-grFuXZ9U&feature=related"

I've been reading about the SR-71 and the J58 engine and I'm confused about what I've read about the inlet spike. The spike would start out extended 3 feet but as speed (Mach) went up it would retract, up to 26 inches when at Mach3.2. This confuses me as I thought you'd always want the...

dear all, some literature which I'm read, measuring blow by of engine can be execute use the pipe. not use with pressure gauge. how to measuring and calculating this if we must be use by pipe (not by pressure gauge)...? here is the ilustration...(attach) rgrds =wahyudi.jr=

The new issue of the mechanical efficiency of the new 4 stroke engine.What will have the efficiency of the engine, which increases its volume swept by two times slower rotating crankshaft- piston systems ?? Two times slower or inertia four times smaller. Regards Andrew

So I'm back home from uni for afew days during summer. My dad has a little bike 2 stroke engine that won't start, so he has given me the job of attempting to get the little thing to start. The spark plug works. I've taken off the top of the engine block and fitted a fresh seal ontop of the...

I think i know how the ramjet works at supersonic speeds, because of the shock wave the air particles traveling through the inside of the tube converge and bump into each other and because the air cannot expand it slows down, increasing the pressure, so when the air escapes it expands very...

Is there any way of calculating rev-gain based on engine specs, like bore and stroke? What other variables are involved? Maybe I am thinking of rev-gain in a wrong sense. If the former isn't capable, is it capable to find out the rotating mass of an engine, like the force the engine has to...

Powerful rotary engine? This is a powerful rotary internal combustion engine. When rotor round one time, engine work six times.My mechanical design aim was to create a power for UAV,MAV, robotics, mini-generators; engine size is very small, can be forged or EDM etching method of mass...

let use injector as an example Many of the fuel injector problems are centered around the dirty fuel injector. If a fuel injector is dirty i.e. the injector is clogged, the fuel spraying into the engine is going to be restricted. Hence if the fuel injector is dirty you are going to face...

Homework Statement Why does an IC engine generate about the same maximum torque over a range of engine speeds but the maximum power at only one speed? Homework Equations None. The Attempt at a Solution For max power, the best I can come up with is that since torque does not drop as...

Homework Statement A railway wagon runs on frictionless rails and is pulled by an engine traveling at 10 ms−1 . The wagon is loaded at constant rate with 1000 kg of coal, dropped vertically from rest for a time of 2 s. What is the work done by the engine to keep the wagon moving at...

Hi I'm need to check if the securing arrangements for a load are adequate... Weight of engine and steel transport stand - 7826 kgs secured to a wooden flat bed trailer by 4, 3.2 tonne SWL chain blocks (1 at each corner) maunfacturer states that the securing arrangement must withstand a...

I am in the airport right now and I was wondering if there is someway to determine the speed of the aircraft engine from the sound the engine makes inside the plane. I have a audio analysis program and I can determine the frequency of the sound inside the airplane. Is there any way to...

Hi, Could someone tell me the rough temperature the air gets to under compression, just prior to the diesel being injected and auto igniting? thanks in advance

if i were to connect a central axis to the turbine in a small jet engine and down gear it using planetary gearing is there potential for jet a type engine to put out some "real" tourque is there a way i could figure this in foot lbs using the thrust? absolute pressure? thermal efficiency?

Homework Statement A Carnot engine runs between a high temperature of 500 C and a low temperature of 50 C. The isothermal expansion (upper branch) occurs between a volume of 0.5L and 1.0L. The isothermal contraction (lower branch) occurs between 2.0L and 1.0L. There are 2 moles of gas...

Homework Statement A railway wagon runs on frictionless rails and is pulled by an engine traveling at 10 ms−1 . The wagon is loaded at constant rate with 1000 kg of coal, dropped vertically from rest for a time of 2 s. What is the work done by the engine to keep the wagon moving at...

Homework Statement A heat engine operating between temperatures of 500 K and 300 K is used to lift a 10-kilogram mass vertically at a constant speed of 4 meters per second. (a) Determine the power that the engine must supply to lift the mass. (b) Determine the maximum possible efficiency...

how electric motor can have full torque at start? is it because magnetic forces are in phase with turning moment curve of rotor of electric motor. i mean the peak of magnetic forces and peak of turning moment occurs at same time. if we implement this in IC engine does it to can have full torque...

Hi Guys, I would like to write some software to teach people to tune internal combustion engines. More specifically, as some of you may know, an engine is controlled by two 2D grids or 'maps' which have engine load on one axis and engine RMP on the other. One map tells the engine how early to...

A Carnot air conditioner takes energy from the thermal energy of a room at 76°F and transfers it as heat to the outdoors, which is at 96°F. For each joule of electric energy required to operate the air conditioner, how many joules are removed from the room? Attempt at problem 76 + 273 = 349 96...

For a personal project, I am analysing the physics in the Source video game engine and comparing it with real life. I have set up in the engine a platform which increases in inclination from 0 to around 70 degrees. On this platform there are four, equally weighted cubes each with a...

My question is referring to the first picture of the SR-71 on wikipedia. http://en.wikipedia.org/wiki/Sr-71 What are those dark streaks on the wings of the aircraft near the engine?

When I got my motorbike it had a non-standard rear sprocket with two extra teeth. I decided to swap it for a standard one. I expected to get a better overall mpg, but it didn't change noticeably. So... An engine has a red line at 14000 rpm. Peak power is delivered at 12000 rpm. Driving...

how would you find the correct formula for the temp at state 3 and 4. i found it for 1 and 2