Gas and Oil Engines, Simply Explained Trivia Quiz Questions and Answers

What is the name of the four-stroke cycle that became the standard for most gas engines by the early 1900s?

Diesel Cycle
Otto Cycle
Atkinson Cycle
Miller Cycle

Correct Answer: Otto Cycle

Correct Answer Explanation: The Otto cycle, named after Nikolaus Otto, is a four-stroke cycle that involves suction, compression, power (expansion), and exhaust strokes. It became the standard for most gas engines due to its efficiency and reliability.

In early gas engines, what was the primary method used for igniting the fuel-air mixture?

Electric spark
Hot tube
Chemical reaction
Laser ignition

Correct Answer: Hot tube

Correct Answer Explanation: Early gas engines often utilized a hot tube ignition system. A heated tube, typically made of iron or porcelain, was placed in the combustion chamber. The hot tube would ignite the fuel-air mixture as it passed by, initiating combustion.

Which type of governor is used to regulate engine speed by responding to changes in the engine’s rotational inertia?

Centrifugal governor
Inertia governor
Electronic governor
Hydraulic governor

Correct Answer: Inertia governor

Correct Answer Explanation: An inertia governor works by sensing changes in the engine’s rotational inertia. As the engine speed increases, the inertia of the governor’s moving parts resists the change, creating a force that acts on a control mechanism to regulate the engine speed.

What is the main purpose of valve timing in an engine?

Regulating fuel injection
Controlling engine temperature
Optimizing engine efficiency
Preventing backfire

Correct Answer: Optimizing engine efficiency

Correct Answer Explanation: Valve timing plays a crucial role in engine efficiency. Proper valve timing ensures that the intake and exhaust valves open and close at the right moments, allowing for optimal filling of the cylinders with fresh air and efficient expulsion of exhaust gases.

In early oil engines, what was the primary challenge that engineers faced?

Designing efficient fuel injection systems
Converting liquid oil into usable gas
Preventing premature ignition
Controlling engine noise

Correct Answer: Converting liquid oil into usable gas

Correct Answer Explanation: Early oil engines faced the challenge of converting liquid oil into a usable gaseous form. This was achieved through various vaporizer designs, which heated the oil to vaporize it and mix it with air for combustion.

What is the purpose of the air vessel in an oil engine pump?

To reduce noise
To maintain constant pressure
To filter impurities
To regulate fuel flow

Correct Answer: To maintain constant pressure

Correct Answer Explanation: The air vessel in an oil engine pump acts as a pressure reservoir. It helps to maintain a steady flow of fuel to the engine by cushioning pressure fluctuations caused by the pump’s pulsating action.

What is the approximate ratio of air to gas required for a typical explosive mixture in early gas engines?

1:1
5:1
10:1
20:1

Correct Answer: 10:1

Correct Answer Explanation: A typical explosive mixture in early gas engines required approximately ten parts air to one part gas. This ratio ensured a proper mix for efficient combustion while preventing excessive pressures that could damage the engine.

What was the main fuel source used in Robert Street’s first real gas engine in 1794?

Natural gas
Kerosene
Coal tar
Gasoline

Correct Answer: Coal tar

Correct Answer Explanation: Robert Street’s first real gas engine, developed in 1794, utilized coal tar, spirit, or turpentine as its primary fuel source. Coal tar was readily available at the time, making it a practical choice for early engines.

What significant improvement did Barnett introduce to gas engines in 1838?

The use of electric ignition
The principle of compression
The four-stroke cycle
The use of a water jacket

Correct Answer: The principle of compression

Correct Answer Explanation: Barnett, in 1838, introduced the principle of compression to gas engines. By compressing the fuel-air mixture before ignition, the efficiency of the engine was significantly increased, resulting in more power output and reduced fuel consumption.

Which early engine, introduced in 1860, was widely popular but notoriously inefficient?

Otto & Langen’s engine
Lenoir’s engine
Hugon’s engine
Barsanti & Matteucci’s engine

Correct Answer: Lenoir’s engine

Correct Answer Explanation: Lenoir’s engine, introduced in 1860, gained widespread popularity due to its simplicity. However, it was known for its high fuel consumption, consuming a significant amount of gas per horsepower produced.

What is the purpose of the swelling on the exhaust cam in some early engines?

To prevent backfire
To reduce engine noise
To aid in starting the engine
To improve fuel efficiency

Correct Answer: To aid in starting the engine

Correct Answer Explanation: The swelling on the exhaust cam, often referred to as a half-compression mechanism, helps in starting the engine. It allows for partial opening of the exhaust valve during the compression stroke, reducing the compression pressure and making it easier to crank the engine.

What is the primary function of a magneto ignition system in an early gas engine?

To provide a continuous spark for ignition
To regulate engine speed
To control fuel injection
To prevent backfire

Correct Answer: To provide a continuous spark for ignition

Correct Answer Explanation: A magneto ignition system is a self-contained generator that produces the spark for ignition without the need for batteries. It utilizes a rotating magnet to generate electricity, which is then used to create a spark at the spark plug, igniting the fuel-air mixture.

Why is cooling water essential in early gas engines?

To regulate engine speed
To prevent overheating
To improve fuel efficiency
To reduce engine noise

Correct Answer: To prevent overheating

Correct Answer Explanation: Cooling water is essential to prevent overheating in early gas engines. It circulates around the cylinder and exhaust valve, absorbing heat and carrying it away from the engine. This prevents damage to the engine components due to excessive temperatures.

What is the primary reason why early gas engines often required frequent maintenance?

Poor materials
Complex design
Inconsistent ignition
Lack of lubrication

Correct Answer: Inconsistent ignition

Correct Answer Explanation: Early gas engines often required frequent maintenance due to inconsistencies in their ignition systems. Hot tube ignition was unreliable and prone to failure, requiring frequent cleaning and adjustments to ensure proper operation.

What does it mean for the air and gas mixture in an engine to be homogeneous?

The mixture is evenly distributed throughout the combustion chamber
The mixture contains only air
The mixture contains only gas
The mixture is highly flammable

Correct Answer: The mixture is evenly distributed throughout the combustion chamber

Correct Answer Explanation: A homogeneous air-gas mixture is essential for efficient combustion in an engine. It means that the fuel and air are evenly distributed throughout the combustion chamber, ensuring that all fuel is burned completely and without creating pockets of concentrated fuel that can lead to incomplete combustion or backfire.

What is the purpose of the cold portion of the bunsen flame when using a bunsen burner for ignition?

To provide a constant heat source
To prevent backfire
To ensure complete combustion
To heat the ignition tube

Correct Answer: To heat the ignition tube

Correct Answer Explanation: When using a bunsen burner for ignition in early gas engines, the hot portion of the flame is directed at the ignition tube. The cold portion of the flame is not used for heating the tube; it is simply a byproduct of the combustion process.

What is the main purpose of the exhaust cam in an engine?

To regulate engine speed
To control fuel injection
To open and close the exhaust valve
To prevent backfire

Correct Answer: To open and close the exhaust valve

Correct Answer Explanation: The exhaust cam is a rotating component that controls the timing and duration of the exhaust valve’s opening and closing. It ensures that exhaust gases are expelled from the cylinder at the appropriate time, allowing for efficient combustion and reducing backpressure.

What is the role of the size and shape of the cams in an engine?

To regulate engine speed
To control fuel injection
To determine valve timing
To prevent backfire

Correct Answer: To determine valve timing

Correct Answer Explanation: The size and shape of the cams are critical in determining the precise timing of the intake and exhaust valves opening and closing. This valve timing is crucial for engine efficiency, performance, and overall operation.

What does the term “half-compression” refer to in early engine design?

The process of compressing the fuel-air mixture before ignition
The partial opening of the exhaust valve during the compression stroke
The use of a water jacket to cool the engine
The use of a magneto ignition system

Correct Answer: The partial opening of the exhaust valve during the compression stroke

Correct Answer Explanation: “Half-compression” refers to a mechanism that allows for the partial opening of the exhaust valve during the compression stroke in early engines. This reduces the compression pressure, making it easier to start the engine.

What is the key characteristic that makes Capel’s oil engine design notable?

Its use of a magneto ignition system
Its ability to operate on a variety of fuels
Its simplicity and adaptability from gas engines
Its high fuel efficiency

Correct Answer: Its simplicity and adaptability from gas engines

Correct Answer Explanation: Capel’s oil engine design was notable for its simplicity and the fact that it could be easily adapted from existing gas engine designs. This made it a popular and practical choice for early oil engine users.

What is the primary function of a vaporizer in an early oil engine?

To filter impurities from the oil
To convert liquid oil into gas
To control fuel injection
To regulate engine speed

Correct Answer: To convert liquid oil into gas

Correct Answer Explanation: A vaporizer in an early oil engine was a key component used to convert liquid oil into a usable gaseous form for combustion. It heated the oil to vaporize it and then mixed it with air for efficient combustion.

Which of the following early engines was known for its use of automatic ignition by compression heat?

Otto & Langen’s engine
Lenoir’s engine
Hugon’s engine
Hornsby-Akroyd’s engine

Correct Answer: Hornsby-Akroyd’s engine

Correct Answer Explanation: Hornsby-Akroyd’s engine was a notable early oil engine design that utilized automatic ignition by compression heat. It used a hot bulb combustion chamber, where the compressed air-fuel mixture was ignited by the heat of the bulb itself, eliminating the need for external ignition sources.

What is the main component of coal gas that contributes to its flammability?

Carbon dioxide
Hydrogen
Nitrogen
Oxygen

Correct Answer: Hydrogen

Correct Answer Explanation: Coal gas is composed of various gases, with hydrogen being the most abundant and contributing significantly to its flammability. Hydrogen is a highly combustible gas, making coal gas a suitable fuel source for early gas engines.

What is the purpose of the annular space in the Capel oil engine vaporizer?

To filter impurities
To regulate fuel flow
To mix air and oil vapor
To prevent backfire

Correct Answer: To mix air and oil vapor

Correct Answer Explanation: The annular space in the Capel oil engine vaporizer was designed to facilitate the mixing of air and oil vapor. This ensures a proper mixture for combustion, preventing incomplete burning and maximizing engine efficiency.

What is the main difference between an atmospheric gas engine and a compression ignition engine?

The method of ignition
The type of fuel used
The number of strokes in the cycle
The use of a water jacket

Correct Answer: The method of ignition

Correct Answer Explanation: The main difference between an atmospheric gas engine and a compression ignition engine lies in the method of ignition. Atmospheric gas engines utilize external ignition sources, such as a flame or a hot tube, to ignite the fuel-air mixture. Compression ignition engines rely on the heat generated by compressing the air to ignite the fuel, eliminating the need for external ignition.

What is the approximate value of the compression ratio in early gas engines?

Correct Answer: 4:1

Correct Answer Explanation: Early gas engines typically had a compression ratio of around 4:1. This means that the volume of the cylinder at the beginning of the compression stroke was four times larger than the volume at the end of the stroke.

What is the primary advantage of using a magneto ignition system over a battery-powered system?

Increased fuel efficiency
Reduced engine noise
Elimination of the need for batteries
Improved reliability

Correct Answer: Elimination of the need for batteries

Correct Answer Explanation: A magneto ignition system eliminates the need for batteries, making it a more self-contained and reliable ignition source. It generates its own electricity through a rotating magnet, providing a continuous spark for ignition without relying on external power sources.

What was the initial claim regarding the fuel economy of Lenoir engines?

They were very fuel-efficient, consuming half the fuel of a steam engine.
They were relatively fuel-efficient, consuming slightly less fuel than a steam engine.
They were fuel-inefficient, consuming more fuel than a steam engine.
They were extremely fuel-inefficient, consuming significantly more fuel than a steam engine.

Correct Answer: They were very fuel-efficient, consuming half the fuel of a steam engine.

Correct Answer Explanation: Lenoir engines were initially advertised as being very fuel-efficient, claiming to consume only 3.4 shillings per day, half the cost of operating a steam engine. However, these claims proved to be inaccurate.

What was the actual fuel consumption of Lenoir engines in practice?

They consumed about half the fuel of a steam engine.
They consumed about the same amount of fuel as a steam engine.
They consumed about twice the fuel of a steam engine.
They consumed significantly more fuel than a steam engine.

Correct Answer: They consumed significantly more fuel than a steam engine.

Correct Answer Explanation: The actual fuel consumption of Lenoir engines was significantly higher than advertised. They often consumed up to 105 cubic feet of gas per horsepower per hour, making them much less fuel-efficient than claimed.

What is the approximate degree at which the exhaust valve opens before the crank reaches bottom dead center?

5°
10°
15°
20°

Correct Answer: 10°

Correct Answer Explanation: The exhaust valve typically opens about 10° before the crank reaches bottom dead center in early engines. This allows some of the exhaust gases to escape before the compression stroke begins, reducing backpressure and improving engine efficiency.

What is the approximate degree at which the exhaust valve closes after the crank reaches bottom dead center?

15°
25°
35°
45°

Correct Answer: 35°

Correct Answer Explanation: The exhaust valve typically closes about 35° after the crank reaches bottom dead center. This ensures that all the exhaust gases are expelled from the cylinder before the intake valve opens, allowing for a fresh air-fuel mixture to be drawn in for the next combustion cycle.

What is the main purpose of the cooling water passages in an early gas engine?

To reduce noise
To prevent overheating
To improve fuel efficiency
To regulate engine speed

Correct Answer: To prevent overheating

Correct Answer Explanation: The cooling water passages in an early gas engine are designed to circulate cooling water around the hottest parts of the engine, such as the cylinder and exhaust valve. This prevents overheating and damage to the engine components due to excessive temperatures.

What is the approximate percentage of hydrogen in coal gas?

Correct Answer: 50%

Correct Answer Explanation: Coal gas is composed of various gases, with hydrogen being the most abundant component at approximately 50%. Hydrogen’s high flammability makes coal gas a suitable fuel source for early gas engines.

What is the main advantage of using a four-stroke cycle over a two-stroke cycle in gas engines?

Increased power output
Improved fuel efficiency
Reduced engine noise
Simpler design

Correct Answer: Improved fuel efficiency

Correct Answer Explanation: The four-stroke cycle generally offers improved fuel efficiency compared to a two-stroke cycle. This is because the four-stroke cycle allows for a more complete combustion process and reduces the amount of unburned fuel that escapes through the exhaust.

What is the main purpose of the hot bulb combustion chamber in a Hornsby-Akroyd engine?

To preheat the fuel
To provide a source of ignition
To reduce engine noise
To improve fuel efficiency

Correct Answer: To provide a source of ignition

Correct Answer Explanation: The hot bulb combustion chamber in a Hornsby-Akroyd engine serves as a source of ignition. The compressed air-fuel mixture is ignited by the heat of the hot bulb itself, eliminating the need for external ignition sources.

What is the main advantage of using a centrifugal governor over an inertia governor in early engines?

It is simpler to design and manufacture.
It is more responsive to changes in engine speed.
It is more accurate in regulating engine speed.
It is more durable and reliable.

Correct Answer: It is more responsive to changes in engine speed.

Correct Answer Explanation: Centrifugal governors are generally more responsive to changes in engine speed compared to inertia governors. They use the centrifugal force generated by rotating weights to regulate engine speed, providing a faster and more sensitive response to speed variations.

What is the main reason for using a water jacket in early gas engines?

To reduce engine noise
To prevent overheating
To improve fuel efficiency
To regulate engine speed

Correct Answer: To prevent overheating

Correct Answer Explanation: A water jacket is a key component in early gas engines, designed to circulate cooling water around the cylinder and exhaust valve. This prevents overheating and damage to the engine components due to excessive temperatures generated during combustion.

What is the name of the process that converts liquid oil into a usable gaseous form for combustion in early oil engines?

Vaporization
Combustion
Compression
Ignition

Correct Answer: Vaporization

Correct Answer Explanation: Vaporization is the process of converting liquid oil into a usable gaseous form for combustion in early oil engines. This is achieved by heating the oil to a temperature that vaporizes it, creating a gas that can be mixed with air for efficient combustion.

What is the main function of the air vessel in an oil engine pump?

To filter impurities from the oil
To regulate fuel flow
To maintain constant pressure
To prevent backfire

Correct Answer: To maintain constant pressure

Correct Answer Explanation: The air vessel in an oil engine pump acts as a pressure reservoir, helping to maintain a steady flow of fuel to the engine. It cushions pressure fluctuations caused by the pump’s pulsating action, ensuring a consistent fuel delivery to the engine.

What is the primary purpose of the exhaust cam in an engine?

To open and close the exhaust valve
To control fuel injection
To regulate engine speed
To prevent backfire

Correct Answer: To open and close the exhaust valve

What is the main advantage of using a hot tube ignition system over an electric spark ignition system in early engines?

It is simpler and less expensive to manufacture.
It is more reliable and less prone to failure.
It is more efficient in igniting the fuel-air mixture.
It produces a more powerful spark.

Correct Answer: It is simpler and less expensive to manufacture.

Correct Answer Explanation: Hot tube ignition systems were simpler and less expensive to manufacture compared to electric spark ignition systems in early engines. They were also relatively reliable, although they required frequent cleaning and adjustments to ensure proper operation.

What is the primary purpose of the cooling water passages in an early gas engine?

To reduce noise
To prevent overheating
To improve fuel efficiency
To regulate engine speed

Correct Answer: To prevent overheating

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