1. Z

    Carnot engine question help

    I've been stuck on this question for a long time ; here is what i have tried so far: In a well-insulated refrigeration unit, a Carnot engine using an ideal gas is driven by a 1KW electric motor (80% efficient) to freeze water. Assuming that the temperature of the thermal sink is 20 °C...
  2. I

    Working out Thrust of a Turbojet Engine

    Air at 7 °C enters a turbojet engine at a rate of 20kg/s and at a velocity of 300m/s (relative to the engine). Air is heated in the combustion chamber at a rate 20,000 kJ/s and it leaves the engine at 427 °C. The enthalpy of air at inlet and outlet of the engine is 280.13 kJ/kg and 713.27 kJ/kg...
  3. M

    Rotor and power of engine

    The question and answer that I have problem understanding is as follows: A helicopter of mass 800 kg rises to a height of 170 metres in 20 seconds, before setting off in horizontal flight. Calculate the potential energy gain of the helicopter, and hence estimate the mean power of its engine...
  4. J

    airplane engine

    If the right wing right engine suddenly fails.how the rudders and how must be moved so that airplane maintains its attitude and flies straight (assuming the plane is on air not landing)
  5. J

    airplane engine

    If the right wing right engine suddenly fails.which of the two rudders and how must be moved so that airplane maintains its attitude and flies straight (assuming the plane is on air not landing)
  6. C

    Finding volumetric flow rate of heat engine

    A Heat Engine has a thermal efficiency of 40% at a steady power output of 30kW. Calculate the required volumetric fuel flow in L/Hr ( litres/hour) if the fuel has a density of 850 kg/m^3 and an energy content of 45 MJ/kg.
  7. T

    Newcomen's Atmospheric Engine

    Hi All, I just finished this... Take a look! Atmospheric Engine | THERMO Spoken Here! JP
  8. T

    The Jet Engine

    Good morning everyone, I had several questions regarding basic thermodynamics. After going to Paris Airshow (Le Bourget), lot's of questions came to my mind after looking at those beautiful Jet engines... I have always had a very basic understanding on these engines: a fan, a compressor...
  9. A

    Jet engine Brayton Cycle help

    Can anyone help me find the errors in this real cycle h-s diagram of a jet engine? I attached the image. Thank you!
  10. K

    Why engine efficiency drops for light loads?

    It is known that automotive engine efficiency (ie. fuel efficiency) is maximum at a specific range of medium loads. If we go higher than this range, the efficiency drops. If we go lower than these loads, the efficiency drops as well. Do we know the reasons for that? I am particularly interested...
  11. T

    Necomen's Atmospheric Engine

    Hi All. Tommy Newcomen's steam engine ran in 1712 ~ 300 years past. Here's my "physics proof" that it worked.. Atmospheric Engine | THERMO Spoken Here!
  12. kelsiu

    Is Carnot engine the only reversible engine?

    Is Carnot engine the only form of reversible engine? Is it possible to have a different form of reversible engine that goes through different processes? For a standard Otto cycle working with ideal gas, theoretically the two processes involving isochoric pressure change can be reversible...
  13. J

    Volumetric Efficiency of 4 cylinder 4 stroke engine

    I have been asked to calculate the following problem and I am struggling with calculating the volumetric efficiency part c. So far I have calculated: A 4 cylinder 4 stroke engine of 78mm bore and 105mm stroke develops an indicated power of 47.5kW at 4400rpm. The air/fuel ratio is 21kg air/kg...
  14. I

    Internal Combustion Engine (Injectors)

    I need a solution to this problem. An automobile has a 3.2-litter, five-cylinder, four-stroke cycle diesel engine [8] operating at 2400 RPM. Fuel injection occurs from 20° bTDC to 5° aTDC. The engine has a volumetric efficiency of 0.95 and operates with fuel equivalence ratio of 0.80...
  15. D

    Airflow into an engine

    Hello all, this isn't a school related question (although I am currently in a fluid mechanics class) but I'm just double checking and this seemed like the most logical place to ask. If I have a length of tube and I were to move it at 10mph then the air traveling through it is traveling at...
  16. G

    Combustion engine calculations

    Hello everybody here, Well, i am working on internal combustion engine calculations, taking inputs from engine simualtor software, and make my own calculations to compare with the software output and spreadsheet it in excel file, take a look at the software website...
  17. T

    Non – stop engine (II)

    Dears, Few months ago I had chance to put my thread here to say about a model of a non stop engine. Now it has been improved and works well. I would like to introduce again my new model here. 1. Tools and facilities: - The main component of this model is a wooden toy with dragonfly shape...
  18. T

    Non – stop engine

    Dears, I am investigating a way to make an engine that can run continuously. I do not declare that it is a perpetual motion. However, my result until now is so positive. 1. Tools and facilities: - The main component of this model is a wooden toy with dragonfly...
  19. C

    Kender Solar Engine

    Dear Forum, I have run across a very interesting machine that I was wondering if someone could comment on. It is a version of the Sterling Engine, that uses a turbine instead of a piston. Supposedly, they are close to a finished product that will "revolutionize energy production". Here is a...