Combustion Eng Terms

Which is not a viscosity rating?

Entropy degrees API

Percent excess air is the difference between the air actually supplied and the theoretically required divided by

The theoretically air supplied

What is the apparatus used in the analysis of combustible gases?

Calorimeter

Percent excess air is the difference between the air actually supplied and the theoretical air divided by

The theoretically air supplied

The viscosity of most commercially available petroleum lubricating oil changes rapidly above

180 F

When 1 mol carbon combines with 1 mol oxygen

1 mol carbon dioxide

What are the immediate undersirable products from the petroleum based lubricating oil when subjected to high pressure and temperature?

Gums,resins and acids

What kind of bonding do common gases that exist in free state as diatomic molecules experiences?

Covalent bonds

An Orsat’s apparatus is used for

Volumetric analysis of the flue gas

A theorem that states that the total property of a mixture of ideal gases is the sum of the properties that the individual gases would have if each occupied the total mixture volume alone as the same temperature

Gibbs theorem

A small enough particles suspended in a fluid  will exhibit small random movements due to the statistical collision of fluid molecules on the particle’s surface. This motion is called

Brownian motion

When two or more light atoms have sufficient energy(available only at high temperature velocities) to fuse together to form a heavier nucleus the process called

Fusion

What is the residue left after combustion of a fossil fuel?

Ash

What is formed during incomplete combustion of carbon in fuels?

Carbon monoxide

A gas produced by the combustion of fuel oil and cannot be found in the flue gases is:

Hydrogen

Which of the following chemical reactions in which heat is absorbed?

Endothermic reaction

A chemical reaction in which heat is given off

Exothermic reaction

A colorless, odorless mixture of nitrogen and oxygen with traces of other gases water vapor and same impurities.

Air

The transfer of air and air characteristics by horizontal motion is called

Advection

Properties of non- reacting gas mixtures are given by

Volumetric weighting for molecular weight and density, and geometric weighting for all other properties except entropy

The process of separating two or more liquids means of the difference in their boiling point.

Fractional distillation

The gaseous products of combustion of a boiler which contains carbon dioxide, carbon monoxide, oxygen, nitrogen and water vapor is called

Flue gas

A substance whose burning with oxygen yields heat energy such as coal, petroleum and natural gas.

Fuel

A type of radiation consisting of singly charge particles that generate to intermediate distances.

Beta radiation

Stoichiometric ratio is

Chemically correct air- fuel ratio by weight

The increase in velocity past the throat is due to the rapid decrease in the:

Fluid density

In an oxidation – reduction chemical reaction, all of the following occur except:

Nuclear fusion

The residual oil left after distillation of gasoline and kerosene from crude petroleum; yellow to brown oil, used as a diesel fuel and for enriching water gas.

Gas oil

A fuel gas obtained by the destructive distillation of soft coal is called

Coal gas

Removing of impurities from a gas by bubbling it through liquid purifying agent is called

Gas scrubbing

During the fusion process, mass is lost and converted to energy according to:

Einstein’s law

A finely divided carbon deposit by the smoke or flame is called

Soot

Rare gases such as helium, argon, krypton, xenon and radon that are non-reactive are called

Inert gases

Kinematics and dynamic viscosity vary from each other only by a factor equal to the:

Fluid density

The following properties are different for isomers of the same chemical compound except

Number of atoms in a mole of each isomers

Atomic weights of the elements in the periodic table are not whole numbers because of:

The existence of isotopes

The tendency of a pure compound to be composed of the same elements combined in a definite proportion by mass

The law of definite proportions

How do you call of removing of impurities from a gas by bubbling it through a liquid purifying agent?

Gas scrubbing

What is the effect of catalyst in a chemical reaction?

Lower the activation energy

The relationship between the concentration of products and reactants in a reversible chemical reaction given by

The equilibrium constant

What fuel gas obtained by the destructive distillation of soft coal

Coal gas

The process of splitting the nucleus into smaller fragments.

Fission

The ash that is removed from the combustor after fuel is burn is the:

Bottom ash

A mixture of hydrogen and carbon monoxide made by passing steam over hot coke.

Water gas

All of the following are true of non-stoichiometric reactions except

Non-stoichiometric reactions are rare in the combustion process

It is the ratio of the volume at the end of heat addition to the volume at the start of heat addition

Cut-off ratio

Piston rings are made of:

Cast iron

Loss power is due to:

Low injection pressure

A branch system of pipes to carry waste emissions away from the piston chambers of an internal combustion engine is called

Exhaust manifold

The type of filter where the filtering elements is replaceable

Metal edge filter

When four events takes place in one revolution of a crankshaft of an engine, the engine is called:

Two stroke engine

Which of the following does not belong to the group?

Time injection system

Specific heat capacity is an SI derive unit describe as:

J/kg K

A device whose primary function is to meter the flow of refrigerant to the evaporator

Thermostatic expansion valve

The internal combustion engines never work in

Rankine cycle

The general chemical formula for all hydrocarbons is C_nH_m. In different combination of interest, as internal combustion engine fuel, n varies from:

1 to 26

The general chemical formula for all hydrocarbons is C_nH_m. In different combination of interest, as internal combustion engine fuel, m varies from:

2 to 54

The general chemical formula of a paraffin fuel is

C_nH_2n+2

Naphthenes and olefins are types of hydrocarbons with chemical formula of:

C_nH_2n

Which of the following types of hydrocarbons have chemical formula of C_nH_2n-2?

Diolefins

Which of the following types of hydrocarbons have chemical formula of C_nH_2n-4?

Asphaltics

What is the chemical formula of an aromatic type of hydrocarbon fuels?

C_nH_2n-6

At atmospheric condition, hydrocarbon molecules with a low number of carbon atoms, 1 to 4 are

Gases

Hydrocarbons with 5 to 15 carbon atoms are:

More or less volatile light oils

Hydrocarbons with 16 to 26 carbon atoms are referred to as :

Heavy oils

In a four stroke engine if a valve opens 25 before B.D.C. and close 10 after T.D.C the valve should be:

Exhaust valve

In a hot wire anemometer the rate of heat loss from sensing element is a function of:

Velocity of flow

Sticking valves

Valve springs of defective material

Detonation of pinging noise is due to :

Late timing of fuel injection

The thermal efficiency of a dual cycle engine with fixed compression ratio and fixed quantity of heat and with increase in pressure ratio, will

Increase

Scavenging efficiency of a four stroke diesel engine is:

Between 95% and 100 %

Volumetric efficiency of a well designed engine may be in the range of:

75 to 90%

During idling in  compression ignition engine the air fuel ratio may be of the order of:

30

Vapor lock is

Complete or partial stoppage of fuel supply   because of vaporization of fuel in supply   steam

Flash point of liquids is the temperature at which:

The fuel emits vapors at a rate which produces and inflammable mixture with air

The mean effective pressure of a diesel cycle having fixed compression ratio will increase if cut off ratio is:

Increased

Hot spots

Are the spots where heavier functions of fuel are vaporized

Flash point for diesel fuel oil should be:

Maximum 49 C

Morse test is conducted on :

Multi-cylinder engines

Prony brake is used for testing of:

Small engines

Clog point of an oil refer to:

the temperature at which paraffin ad waxes in oil start precipitating

Otto cycle consists of

two isentropic and two constant volumes processes

Diesel cycle consists of:

two isentropic, one constant volume and one constant pressure processes

Which is not correct for calculating air standard efficiency?

Gases dissociate at  higher temperature

The king pin inclination is generally:

Between 2 and 5

For balancing single cylinder engine a counter weight is added to:

Crank

To measure the clearance between the valve and tappet of an automobile engine we use a

Feeler gauge

By supercharging:

Thermal efficiency of the engine can be improve

Speedometer drive is generally taken from:

Front wheel

Odometer is:

An instrument used for distance  measurement

Automobile radiator is filled with:

Soft water

The ignition coil acts as:

A step up transformer

The self starting motor for automobiles is a:

Dc series motor

Starting motor current may be about

25 A

As a rule before the piston are removed, it is essential to remove the :

Piston rings

Common causes for excessive oil consumption

High speed and worn engine

The device that is used for reducing the exhaust noise is called

Muffler

The device that is used to measure the clearance between the valve and tappet of an internal combustion engine is measured by using:

Feeler gauge

Which of the following instrument is used in measuring specific gravity?

Hydrometer

Exhaust gas leakage into the cooling system is most likely occur because of defective:

Cylinder head gasket