What is Engine: Definition and 999 Discussions

An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a heat engine, in which heat from the combustion of a fuel causes rapid pressurisation of the gaseous combustion products in the combustion chamber, causing them to expand and drive a piston, which turns a crankshaft. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, and clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and ultimately motion.

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  1. T

    Basic Vibration Damping and Isolation

    Hello, I am studying and trying to understand Powertrain / Engine mounts used in automotive such as these: http://images.gasgoo.com/MiMwMDRfMDA0Izc4MDA3NzIwMA--/auto-part-engine-torque-strut-mount-engine-mounting-for-buick-enclave-chevrolet-traverse-gmc-acadia-25840458.jpg...
  2. T

    Carnot cycle heat engine max work done

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  3. voltech444

    Oxygen Enriched Internal Steam Compression Ignition Engine (OEISCIE)

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  4. S

    Heat engine efficiency could approach 100%?

    According to Carnot theorem, the higher temperature of a hot side and the lower temperature of a cold side the higher is the efficiency of a heat engine. Does it mean that in theory it could get anywhere close to 100%? If we take in account that 100% efficiency means it is a perpetuum mobile...
  5. C

    What happens when gasoline gets old - chemically and in car engine?

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  6. R

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  7. ajayguhan

    How Does the Efficiency Formula Change for Reversible Heat Engines?

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  8. C

    Torque of a small gasoline engine

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  9. K

    Calculating Heat Engine Efficiency: What is the Energy Input?

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  10. K

    Solving Heat Engine & Refrigerator Problems

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  11. S

    How to design a radiator to dissipate heat generated by a 39 KW rotary engine?

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  12. G

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  13. A

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  14. J

    Engine Coolant Heat Dissipation Calculations

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  15. E

    Highest possible efficiency of an engine

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  16. joema

    Polar graph for engine balance on common types?

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  17. J

    Can Engines Be Disabled with Poison?

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  18. E

    Power of an Engine: Work & Effects

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  19. A

    Effects of inertia forces and friction forces on a piston in engine

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  20. X

    How Does Recirculation Work in Steam Engines?

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  21. D

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  22. R

    Thrust from model engine exhaust

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  23. R

    Need help understanding engine acceleration and relation with torque

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  24. Z

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  25. N

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  26. R

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  27. J

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  28. J

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  29. A

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  30. C

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  31. N

    Can a Jet Engine be Created Using a Traffic Cone Design?

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  32. V

    My engine oil is green color. Its normal?

    today i did a oil change on my outboard engine. i found out the oil is green, its normal? If yes, why the oil will be green color? because i fill the new oil is golden color.
  33. U

    Can Polystyrene Withstand the Heat in a Stirling Engine Displacer?

    Hey Guys, I'm working on a Stirling engine to show my nephew. I have made one before that runs off off coffee water but now I'm planning on making a system which will use a heat source around 90-125°C and I do not know if polystyrene will melt or not. So if you guys have any suggestions for a...
  34. Nathanael

    Engine with constant power; Time taken to finish track?

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  35. W

    Has this engine cylinder/ block design be done before,would it work?

    I believe artillery guns and barrels that are highly pressurised often use shrink fitting (heating up a tube causing it to expand allowing it to be fitted over a smaller tube which it will apply an inward pressure on when it cools) to oppose the pressure from inside the barrel. Could this...
  36. S

    Heat Engine efficiency Problem

    Please help me with the question below with a proper explanation and also suggest me a reference to read for the same. Thank you! A solar collector receiving solar radiation at the rate of 0.6 kW/m2 transforms it to the internal energy of a fluid at an overall efficiency of 50%. The fluid...
  37. I

    Understanding Heat & Work: An Engine Explained

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  38. N

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  39. G

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  40. N

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  41. 9

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  42. K

    Lockheed Martin F-35 Lightning II engine power?

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  43. T

    What is the Minimum Time for Acceleration in an Auto Engine Power Problem?

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  44. S

    Relation between SFC vs RPM in diesel engine?

    What is the relation between sfc vs rpm in diesel engine and why does it happen like that ? what is relation between air flow vs rpm ??
  45. K

    Gasoline engine - max torque and efficency

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  46. A

    Engine Test Bed Fourier Analysis

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  47. A

    Exploring Diesel Engine Friction and Fuel Mass Flow Rate

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  48. zoobyshoe

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  49. R

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  50. J

    Does Constant Engine Power Guarantee Constant Acceleration?

    Homework Statement a cars engine produces constant power therefore the cars speed will increase at a constant acceleration. is this true or false Homework Equations Power=w/t work=fd so P=mad/t The Attempt at a Solution so if p is constant it appears a must be constant...
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