Homework Statement
A car with mass 1000 kg accelerates from 0 m/s to 40 m/s in 10.0 s. Ignoring air resistance. The engine has a 22% efficiency, which means that 22% of the thermal energy released by the burning gasoline is converted into mechanical energy.
a) What is the average...
Homework Statement
21. A heat engine operates in a cycle between temperatures 700 K and 400 K. The heat input to the engine during each cycle is 2800 J. What is the maximum possible work done by the engine in each cycle?
(A) 1200 J
(B) 1600 J
(C) 2100 J
(D) 2800 J
(E) 4400 J
I...
I have designed a powerful rotary internal combustion engine. When rotor round one time,engine work six times. It can be used UAV power or portable generator or soldier power.for it is a high speed machine ,we can pay few attention about the seal problem.you know,when the speed of the engine is...
Hey, I am working on a project and yahoo answers hasn't been much help. I am building a light weight race truck and I was hoping someone in here had heard of a high horse power diesel engine that wasn't heavier then the rest of the truck :)
Homework Statement
http://img291.imageshack.us/img291/7786/effx.jpg
Homework Equations
e=1-1/(V1/V2)^(gamma-1)
The Attempt at a Solution
This is a practice test where he gives the solutions, as you can see the first thing he asks for is the efficiency, and lists the answer as...
Homework Statement
A Carnot engine working with a monatomic gas operating between two temps, 288K and 497K. The engine performs 800 J of net work.
Homework Equations
Q = nRT ln (V final/V initial)
The Attempt at a Solution
I don't have enough info for the above equation. I...
Homework Statement
I=\frac{p_{ave}}{4\pi r^{2}} is derived on the assumption that the transmitting medium does not absorb energy. It is known that the absorption of sound in dry results in a decrease in energy of about 8 dB/km. The intensity of sound at a distance of 120 m from a jet engine is...
Ok so I'm no grad student asking for help on a research project. I'm a senior in high school that is totally burnt out when it comes to the daily grind. I think I found a project, that hopefully is possible, and that will take me oodles of time and feed my hunger for education without a stupid...
Homework Statement
A Carnot engine has 40 g of helium gas as its working substance. It operates between two reservoirs of temperatures T1 = 400°C and T2 = 60°C. The initial volume of the gas is V1 = 2.0 X 10-2 m3, the volume after isothermal expansion is V2 = 4.0 X 10-2 m3, and the volume...
Homework Statement
I'm trying to find the final temperature of a carnot engine with two finite thermal reservoirs. We're told that the heat capacities for both reservoirs are constant (and equal) and to regard the change in each reservoir's temperature during any 1 cycle as negligible...
Homework Statement
An ideal Carnot engine operates between a heat reservoir and a block of ice of mass M. An external energy source maintains the reservoir at a constant temperature T_{h}. At time t=0 the ice is at its melting point T_{0}, but it is insulated from everything except the...
Homework Statement
Assume that the speed of sound in the air is V=343m/s. Use the generalized form of the Doppler equation to solve the following problem.
You are standing 100m away from a long straight road while a fire engine passes by along the road. The fire engine is equipped with a...
[b]1.A heat engine is rejecting 200btu/h and 30% efficient, how much power does it use in watts?
[b]2. QH=w+QC and power=energy/time (1kwh=3412btu)
and a power diagram: QC= wasted heat, w=work
QH
l
30%l---->W
l
QC
[b]3. 200btu/h(1kwh/3412btu)(1000w/1kw)=58.6watts...
i have diagram of the turning moment in flywheel in internal combustion engine , i want to determine the mass of moment of inertia of the flywheel needed to keep speed fluctuation < or equal 1.5% at engine speed 560 rpm ?
http://img534.imageshack.us/img534/1765/57306264.jpg
Homework Statement
An ideal monatomic gas is confined to a cylindrical container having a movable, yet "snuggly-fitting," lid that slides up and down to accommodate changes in pressure and volume. The diagram shown below, outlines the steps in a heat cycle starting at position A and moving...
Homework Statement
A car of mass 500 kg has a maximum speed of 40 ms-1 on a level road with the engine of the car working at a constant power of 20 kW. The resistance to motion is proportional to the square of the speed.
(i) find its acceleration when the speed is 20 ms-1
(ii) find the...
Given :
QH=W+QC and Power= E/t or W/t
A heat engine is attached to a 200W lamp. If we power the lamp for 1 hour and extract 700 btu from the heat source, how much heat is rejected?
Attempt:
200w(3.412btu/1w) = 682.4 btu now, 700 btu-682.4 btu =17.6 btu rejected??
Homework Statement
The diagram below shows the thermodynamic cycle of a diesel engine. The compression ratio is the ratio of maximum to minimum volume; r=\frac{V_{1}}{V_{2}}. In addition, the so-called cutoff ratio is defined by r_{c} = \frac{V_{3}}{V_{2}}. Find an expression for the...
Hi, I'm not sure if I've got this in the right section, but I'm hoping someone can point me in the right direction.
I'm trying to create a model of what's actually happening during the combustion cycle in an engine and where the energy is going.
As the intake valve closes and the piston...
Morse test!
A morse test is sued to determine the mechanical efficiency of a petrol engine. these are the results
Torque (Nm)
No plugs shorted 91
no1 shorted 63
no2 shorted...
if i have calorific value of mixture, volume at time of compression, bore diameter, can i know the pressure being exerted on the pistons due to the combustion?
Note this is more of a coursework question about the theory behind Carnot engines as opposed to an actual homework question.
Homework Statement
The Attempt at a Solution
So I am reading the theory behind a Carnot Engine and I am a little confused about the cooling stages of the Carnot cycle...
I got a small 16inch folding bike weight 13kgs and managed to shed it down to 9kg and working in weight reduction further... eg using hollow shaft at the peddle and using clips at the axles and replacing to 14inch rims and redoing the frame in lighter stainless 201 - these are my next to-do...
1. I have heard the argument that "the Effort ( Force ) required to move a certain mass by Pulling is greater than the Effort required to move the same mass by Pushing it".
What is the truth regarding this statement and what causes the difference in the applied force to move the same...
Hi guys
I read somewhere that "the actual torque transmitted from the engine to the clutch is the total engine torque subtacted by the amount of torque required to accelerate the inertia of rotating components of engine.i.e:"
T(c) = T(e) - [ I(e) x \alpha(e) ]
where T(c)=Torque at clutch...
I’m from a group that is current working on the theory of a Hydrogen Economy. Our first area of development is the Hydrogen Highway. We are currently seeking help in the form of freelance / work for hire basically engineer(s) that could aid in design and calculations of internal combustion...
Hello,
I am currently doing a project on reciprocating compressed air engine and would like to have explanations about the mechanical design - is it similar to a reciprocating air compressor or steam engine, that is, does it have a conventional piston-cylinder assembly, connecting rod...
Hi,
i am interested to know the major components of the fuel system of a car. I know, these are the major ones:
Fuel Tank, Fuel Pump, Fuel Filter, Injector Valve, Return Lines
but what i am interested is in the fuel system for (1) a single cylinder engine, (2) no carburetor (instead, i am...
Homework Statement
18. (II) At a steam power plant, steam engines work in pairs, the heat output of the first one being the approximate ehat input of the second. Th eoperating temeprautres of the first are 680 degrees C and 430 degrees C, and of the second 415 degrees C and 280 degrees C...
Im looking at designs for a engine, but I am giving myself a headache over something which is probably incredibly obvious. Ill explain it as simply as I can in text and I've drawn a (terrible) paint image to help explain it a bit better.
There are two cylinders. One cylinder needs to have its...
Homework Statement
A heat engine operating between 78.5oC and 204oC achieves 20.6% of the maximum possible efficiency. What energy input will enable the engine to perform 10.2 kJ of work?
The only help I need with this is exactly what equation(s) to use. I would think thermal efficiency...
So, I've been working on an engine design that has been tried already, and nobody has really got it to work the way i think that it should. The engine I'm working with is a Wankel Rotary Engine and what I'm trying to do is make a modern, high-efficiency, high power-output diesel out of it. I'm...
please explain engine braking? the definition i found was " braking effect caused by throttle position induced vacuum in petrol engines".In what way is this better than external braking?
Hey,
I'm an electrical engineering student and I'm trying to design a solar dish which converts the heat from sunlight into electricity. I managed to make a small stirling engine with the results i got from google (The stirling engines made from coke cans). I was wondering how costly...
A jet engine develops 1 * 10^5 n of thrust in moving the airplane forward at a speed of 900 km/h. What is the power developed by the engine?
I thought I needed to convert 900 km/h to m/s, so I did and I got 15000 m/s.
The only equation I see to use for this is:
P = Fvcosθ
When I...
Homework Statement
A steam engine has a cylinder 80cm in diameter with a piston that has a total travel length of 1.8m. Assume that there is no "dead space" between the cylinder head and the piston when the piston is farthest in the cylinder. Steam is piped into the cylinder head from an...
Advice needed please with the design of cooling vents, louvres on the cowling of a radial engine. Plane is a Sukhoi, as per vid links below, 76 inch span 37cc petrol engined radio control. Cooling will be from cutouts in the cowl approx 20 x 80 mm with a flat plate louvre at the leading edge...
Homework Statement
The hot reservoir of a heat engine is steam at 100 while the cold reservoir is ice at 0. In 1.3 of operation, 12 of steam condenses and 59 of ice melts.
What is the power output of the heat engine?
Homework Equations
W=Q_h - Q_c
n=W/Q_h=1 - (T_c/T_h)
Q=ML...
Hi there, my first post on this forum and I hope its in the right place !
My question is this, in an exisitng air-cooled motorcycle engine what is the viability of using heat pipe technology to cool exhaust gas temperature? Using heat pipes to remove heat from exhaust valve areas to external...
What is the fastest speed ever recorded, achieved by a internal combustion piston engine on a land vehicle, and not an aircraft/propeller? I know that some top-fuel dragsters can exceed 300 MPH.
Hi you all
Seaching in internet, I have not found an answer to this:
In a air-gasoline stechiometric mixture, what can be the volumen relationship between the unburned (intake gas) and final exhaust gases?.
I guess temperature is important, but let's consider a normal working...
Homework Statement
Engine: 100 tonnes, with 1,000N frictional force
Train: 400 tonnes, with 20,000N frictional force
Speed = 80km/hour
Engine is exerting a power of 4000kW
Find the tension in the couplings between train and engine
The Attempt at a Solution
I'm not sure where to...
! Cyclic variation of engine torque
If the cylinders fire sequentially according to the fire order 1-2-4-3
What is the pattern of the cyclic variation of each cyclinder engine torque and the resultant engine torque?
can anyone please tell me what is the gas pressure which applies on piston head just after combustion in cylinder
its very urgent and necessary for me to know this
please help me
I once saw an engine study that uses solenoids in compensating engagements much like the internal combustion engine. It was a small contraption but it worked. It used 12v dc current. I am just wondering if the engine can produce enough electricity to recharge the battery it uses if an alternator...
The gas in a 748mL cylinder of a diesel engine has a pressure of 1.72 atm at 306K. What will be the volume of the gas when the piston compresses it to 46.5 atm and 777K?
Hi all,
I have recently been shown a diagram of pressure versus piston position for a particular heat engine. The system is based on a Joule cycle and is designed to take a drive stroke at constant pressure.
Now what I'm trying to understand is, the pressure appears to 'wobble' slightly...