Engine Operation and Basics
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What was the primary energy source for early steam engines?

  • Electricity
  • Petroleum
  • Coal
  • Atmospheric pressure (correct)

    • Which of the following was a challenge in the development of early engines?

  • The use of steel
  • Maintaining a seal between the piston and the cylinder walls (correct)
  • Fuel availability
  • Efficient lubrication

    • Who invented the first practical four-cycle internal combustion engine?

  • James Watt
  • Nikolaus Otto (correct)
  • Rudolf Diesel
  • Gottlieb Daimler

    • Which of the following is NOT a basic requirement for an engine to convert heat energy into mechanical energy?

    <p>A renewable fuel source</p> Signup and view all the answers

    What is the correct sequence of events in an engine cycle?

    <p>Intake, Compression, Power, Exhaust</p> Signup and view all the answers

    Which major engine part provides surfaces for attaching other parts and accessories?

    <p>Cylinder block</p> Signup and view all the answers

    What is the purpose of the main bearing journals inside the cylinder block?

    <p>House the crankshaft</p> Signup and view all the answers

    Which materials are commonly used to make the cylinder block?

    <p>Cast iron and aluminum alloys</p> Signup and view all the answers

    What is the primary function of the water jackets within the cylinder block?

    <p>To allow for the circulation of coolant around the cylinders</p> Signup and view all the answers

    Which of the following best describes a 'dry sleeve' in an engine cylinder?

    <p>A thin, replaceable wear surface that fits into the cylinder walls and is not exposed to the coolant</p> Signup and view all the answers

    What is the function of the oil pan in an engine?

    <p>To serve as a reservoir for lubrication oil</p> Signup and view all the answers

    Which component is bolted to the top of the cylinder block?

    <p>The cylinder head</p> Signup and view all the answers

    What is the main function of the crankshaft in an engine?

    <p>To change the reciprocating action of the pistons into rotary motion</p> Signup and view all the answers

    What are the precision machined bearing surfaces on the crankshaft called?

    <p>Journals</p> Signup and view all the answers

    What is the purpose of the counterweights on the crankshaft?

    <p>To balance the crankshaft during rotation</p> Signup and view all the answers

    Which component is attached to the end of the crankshaft?

    <p>The flywheel</p> Signup and view all the answers

    In a four-stroke engine, where can the valves be located?

    <p>Either in the cylinder block or the cylinder head</p> Signup and view all the answers

    How many crankshaft revolutions are there in a single four-stroke engine cycle?

    <p>Two</p> Signup and view all the answers

    What is the 'Otto cycle' another name for?

    <p>Four-stroke cycle engine</p> Signup and view all the answers

    During the intake stroke of a four-stroke engine, which way does the piston move?

    <p>Downward, toward BDC</p> Signup and view all the answers

    In a four-stroke engine, when is the fuel-air mixture compressed?

    <p>During the compression stroke</p> Signup and view all the answers

    What is the primary function of the power stroke in a four-stroke engine?

    <p>To convert heat energy into mechanical energy</p> Signup and view all the answers

    How many crankshaft revolutions happen in a single two-stroke engine cycle?

    <p>One</p> Signup and view all the answers

    Which of these is NOT a method used for intake and exhaust in two-stroke engines?

    <p>A multi-stage turbocharger</p> Signup and view all the answers

    What is the primary function of the flywheel in an engine?

    <p>To smooth out engine power impulses through momentum.</p> Signup and view all the answers

    What is the purpose of the camshaft in an engine?

    <p>To open and close the valves.</p> Signup and view all the answers

    What is the function of piston rings?

    <p>To prevent pressure and oil leakage.</p> Signup and view all the answers

    What role do connecting rods play in an engine?

    <p>To convert reciprocating motion of the pistons to rotary motion of the crankshaft.</p> Signup and view all the answers

    What action causes the valves to open?

    <p>The cam lobe action from the rotating camshaft.</p> Signup and view all the answers

    What are pistons made of?

    <p>Strong heat-resistant cast iron or aluminum alloys.</p> Signup and view all the answers

    What is essential for correct valve operation?

    <p>The timing of the camshaft to the crankshaft.</p> Signup and view all the answers

    What do valves move inside?

    <p>Precision machined valve guides.</p> Signup and view all the answers

    What is the defining feature of an in-line engine cylinder arrangement?

    <p>Cylinders are placed in a straight line above the crankshaft.</p> Signup and view all the answers

    Which of these is NOT a requirement for combustion to occur?

    <p>Compressed air</p> Signup and view all the answers

    What critical component is needed to ignite the fuel/air mixture in gasoline engines?

    <p>An electrical spark</p> Signup and view all the answers

    Which of these is NOT a method to increase the rate of combustion?

    <p>Breaking the fuel into increasingly larger particles.</p> Signup and view all the answers

    What is meant by the term 'detonation' in the context of engine combustion?

    <p>An uncontrolled explosion due to rapid flame propagation.</p> Signup and view all the answers

    What is the typical compression ratio seen in a gasoline engine?

    <p>8 to 1</p> Signup and view all the answers

    What is one potential negative consequence of higher compression ratios in gasoline engines?

    <p>Pre-ignition.</p> Signup and view all the answers

    What is the primary advantage of diesel engines compared to gasoline engines?

    <p>More efficient in fuel usage.</p> Signup and view all the answers

    What is the approximate fuel to air ratio for an internal combustion engine by weight?

    <p>1:15</p> Signup and view all the answers

    Which of the following describes 'stroke' in an engine?

    <p>The distance a piston travels from top dead center to bottom dead center</p> Signup and view all the answers

    What is the formula for calculating piston displacement (PD) for one cylinder?

    <p>PD = (3.1416 * bore * bore * stroke) / 4</p> Signup and view all the answers

    What is the primary method by which air or air/fuel mixture is drawn into the cylinder of a naturally aspirated engine?

    <p>Atmospheric pressure creating a vacuum during the intake stroke</p> Signup and view all the answers

    According to the content, which of the following is NOT a function of the lubrication system?

    <p>Provide heat to the engine.</p> Signup and view all the answers

    What is power defined as in the context of an engine?

    <p>The rate at which work is accomplished</p> Signup and view all the answers

    Which term describes the turning effect of a force?

    <p>Torque</p> Signup and view all the answers

    According to the provided information, what is used to measure and compare the work capacity of different engines?

    <p>Horsepower</p> Signup and view all the answers

    Study Notes

    Engine Operation

    • An engine converts heat energy to mechanical energy.
    • Engines differ from electrical motors, which convert electrical energy to mechanical energy.
    • Early engines utilized steam and atmospheric pressure.
    • Internal combustion engines (ICEs) use a piston to compress fuel within a cylinder.
    • Early ICEs used various fuel mixtures (coal gas, turpentine vapor, air).
    • Early ICEs had significant issues including size, weight, ignition, friction, and sealing.
    • Petroleum provided usable fuels and lubricants.
    • Otto invented a four-stroke cycle engine
    • This engine has commercial applications
    • Otto cycle engine developed in 1876
    • Rudolf Diesel later adapted this for a diesel engine.

    Basic Parts and Operation

    • Engines require fuel, oxygen, and a heat source for combustion.
    • Methods must be available for compressing, containing, and converting combustion heat to reciprocating and rotary motion.
    • This process occurs in a repeating cycle: This cycle is called compression
    • Filling a cylinder with a combustible mixture.
    • Compressing the mixture into a smaller space.
    • Igniting the mixture and allowing expansion to produce power.
    • Removing the burnt gases from the cylinder.

    Major Stationary Parts

    • Cylinder block: Houses the engine, provides mounting surfaces for other components, holds the main bearings for the crankshaft, and holds the combustion cylinders in the engine.
    • Cylinders are hollow tubes machined, or replaceable sleeves or liners.
    • Cylinders are responsible for combustion chambers and provide a smooth surface for the pistons to move.
    • Cylinder block may contain water jackets or passages.
    • Oil pan/crankcase: Serves as a reservoir for oil located at the bottom of the cylinder block
    • Cylinder head: Encloses top of the cylinders and forms part of the combustion chamber.
    • Cylinder head contains spark plugs or diesel injectors and coolant channels in addition to possibly intake or exhaust ports and valves

    Major Rotating Parts

    • Crankshaft: Converts reciprocating motion of the pistons and connecting rods into rotary motion of the crankshaft. Also contains journals. It is made of steel.
    • Flywheel: Attached to the end of the crankshaft used for steady turning motion.
    • Connecting rods: Connect pistons to the crankshaft, transmitting reciprocating motion into rotary motion.

    Valves

    • Valves open and close passages for the intake and exhaust ports.
    • Exception: Some engines use ports instead of valves.
    • Valves are made of materials that can resist high temperatures.
    • Valves are held closed by springs,opened by cam lobes (camshaft) and located in the cylinder head or cylinder block.

    Two- and Four-Stroke Cycle Engines

    • Four-stroke cycles require two complete crankshaft revolutions per cycle of events (intake, compression, power, exhaust).
    • Two-stroke engines complete a cycle with one crankshaft revolution and two piston strokes.
    • Two-stroke engines often utilize different valve types.

    Engine Lubrication and Cooling

    • Engine lubrication is essential for reducing friction within the engine.
    • Engine cooling is vital because of the heat generated during operation.
    • Engine lubricants and coolants must be specifically selected to handle the specific operating temperature range.

    Measuring Engine Power

    • Horsepower (HP): A measure of power, related to the amount of work done per unit time. A concept invented by James Watt in the 18th century.
    • Torque: A measure of the rotational force, often calculated as Force x Length. Useful for calculating the turning force of a shaft.
    • Horsepower equations: Combining concepts of torque, and RPM
    • Dynamometer is a device to measure torque and power.
    • Different types of horsepower - drawbar, engine, PTO

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Agricultural Mechanics PDF 8203-A Principles of Engine Operation

    Description

    Explore the fascinating world of engine operation and its fundamental components. This quiz covers the transition from early engines to modern internal combustion engines, their working principles, and the innovations by pioneers like Otto and Diesel. Test your knowledge on the key concepts of heat energy conversion and engine cycles.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser