What causes ignition to occur in a diesel engine?

1 Answer

Answer :

When the piston compresses the fuel-air mixture, the spark ignites it, causing combustion

Related questions

Description : The knock in diesel engine occurs due to A. instantaneous and rapid burning of the first part of the charge B. instantaneous auto ignition of the last part of the charge C. delayed burning of the last part of the charge D. reduction of delay period

Last Answer : ANSWER : A

Description : Most high speed compression ignition engine operate on A. dual cycle B. otto cycle C. diesel cycle D.Carnot cycle

Last Answer : ANSWER : A

Description : A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel ... an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.

Last Answer : ANSWER c. The compression ratio of a diesel engine is higher than that of an S.I engine

Description : Which of the following cycle is used for Compression Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Last Answer : Answer b. Diesel cycle

Description : Which of the following cycle is used for Spark Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle

Last Answer : Answer a. Otto cycle

Description : Spark plug is provided in a/an (A) Engine having carburettor (B) Diesel engine (C) Compression ignition engine (D) Both (B) & (C)

Last Answer : (A) Engine having carburettor

Description : iesel engine has less reserve torque then spark ignition because ∙ Torque-speed curve is governed by volumetric efficiency of fuel pump and engine cylinder ∙ Torque is a function of thermal efficiency ∙ Diesel engine has generally low speed engine ∙ None of the above

Last Answer : ∙ Torque is a function of thermal efficiency

Description : If petrol is used in a diesel engine a. higher knocking will occur b. efficiency will be low c. low power will be obtained d. black smoke will be produced

Last Answer : ANSWER a. higher knocking will occur

Description : A fuel of cetane number 40 has the same ignition quality as a mixture of a) 40% cetane and 60% alpha methyl naphthalene b) 40% alpha methyl naphthalene and 60% cetane c) 40% petrol and 60% diesel d) 40% diesel and 60% petrol

Last Answer : Answer: a Explanation: A fuel of cetane number 40 has the same ignition quality as a mixture of 40% cetane and 60% alpha methyl naphthalene as cetane number is counted on cetane percentage.

Description : The probability of knocking in diesel engines is increased by a. High self-ignition temperature. b. Low volatility. c. High viscosity. d. all of the above

Last Answer : ANSWER d. all of the above

Description : Ignition quality of diesel is expressed by a. octane number b. cetane number c. calorific value d. carbon content

Last Answer : ANSWER b. cetane number

Description : The self-ignition temperature of diesel oil compared to petrol is a. higher b. lower c. same d. depends on the quality of fuel

Last Answer : ANSWER a. higher

Description : The probability of knocking in diesel engines is increased by a. High self-ignition temperature. b. Low volatility. c. High viscosity. d. All of the above

Last Answer : ANSWER d. all of the above

Description : The self-ignition temperature of diesel as compared to petrol is a. higher b. lower c. same d. varies

Last Answer : ANSWER a. higher

Description : High aniline point of diesel indicates that, it (A) Is highly aromatic (B) Has a large ignition delay (C) Is highly paraffinic (D) Has a low diesel index

Last Answer : (C) Is highly paraffinic

Description : Cetane number of a diesel fuel is the measure of its (A) Ignition delay (B) Smoke point (C) Viscosity (D) Oxidation stability

Last Answer : (A) Ignition delay

Description : High aniline point of a petrofuel (say diesel) indicates that (A) It is highly aromatic in nature (B) It is highly paraffinic in nature (C) It has a very low diesel index (D) Its ignition quality is very poor

Last Answer : (B) It is highly paraffinic in nature

Description : Compare detonation and diesel knock on the basis of (i) Fuel Ignition Temperature (ii) Compression Ratio (iii) Speed (iv) inlet temperature (v) inlet pressure (vi) cylinder wall temperature (vii) cylinder size 

Last Answer : Comparison between detonation and diesel knock: Parameter To avoid Detonation in SI Engine  To avoid Diesel knock i) Fuel Ignition Temperature High Low ii) Compression Ratio ... Cylinder wall temperature Low High viii) Cylinder size Small Large

Description : In a battery ignition system, the intensity of spark is A. minimum at low engine speed B. minimum at low engine speed and increases with engine speed C. maximum al low engine speed and decreases with engine speed D. maximum at low engine speed

Last Answer : ANSWER : C

Description : Ignition timing of a multi-cylinder SI engine can be adjusted by A. rotating the cam shaft B. adjusting the generator pulley C. rotating the distributor D. adjusting the pump pulley

Last Answer : ANSWER : C

Description : In compression ignition (CI) engine, the compression ratio is a. Cylinder volume / Clearance volume b. Swept Volume / Cylinder Volume c. Clearance volume / Cylinder volume d. Cylinder volume / Swept volume (Ans:a)

Last Answer : In two stroke engine there is one power stroke in _____ of crankshaft rotation. a. 90° b. 180° c. 270° d. 360° (Ans:d)

Description : The compression ratio in a Spark Ignition (SI) engine is generally in between a. 7 to 10 b. 10 to 14 c. 14 to 18 d. 18 to 22 (Ans:a)

Last Answer : Which of the following is not true for two stroke engine as compared to four stroke engine? a. Less cooling is required b. Greater lubrication is required c. More uniform torque on crankshaft d. Complete exhaust of products of combustion (Ans:a)

Description : The tendency of knocking in CI engine reduces by (a) High self ignition temperature of fuel (b) Decrease in jacket water temperature (c) Injection of fuel just before TDC (d) Decrease in injection pressure

Last Answer : Ans :c

Description : The knocking in spark ignition engines can be reduced by a. Retarding the spark. b. Increasing the engine speed. c. Both a and b d. None of these.

Last Answer : ANSWER c. Both a and b.

Description : Which of the following is not related to spark ignition engine? a. fuel injector b. spark plug c. flywheel d. distributor

Last Answer : ANSWER a. fuel injector

Description : Which of the following engine can work on very lean mixture a. Spark ignition engine b. compression ignition engine c. two stroke engine d. Four stroke engine

Last Answer : ANSWER b. compression ignition engine

Description : The knocking in spark ignition engines can be reduced by a. Retarding the spark. b. Increasing the engine speed. c. Both a and b. d. None of these.

Last Answer : ANSWER c. Both a and b

Description : Combustion in compression ignition engine is a. homogeneous b. heterogeneous c. laminar d. turbulent

Last Answer : ANSWER b. heterogeneous

Description : For spark ignition engine, the equivalence ratio of mixture entering the combustion chamber has values (A) for idling and for peak power conditions (B) for both idling and peak power conditions (C) for idling and for peak power conditions (D) for both idling and peak power conditions

Last Answer : ANSWER (B) for both idling and peak power conditions

Description : Rate of burning in the compression ignition engine can be controlled by a. rate of injection of fuel b. rate of air taken into carburetor c. both a. and b. d. none of the above

Last Answer : ANSWER a. rate of injection of fuel

Description : Use of gasoline blend like tetraethyl lead in internal combustion engine a. increases the octane rating of the fuel b. allows engine to operate at higher compression ratio c. avoids auto-ignition of fuel d. all of the above

Last Answer : ANSWER d. all of the above

Description : The compression ratio cannot be increased beyond certain limit as it results in a. auto-ignition of fuel b. detonation c. engine knocking d. all the above

Last Answer : ANSWER d. all the above

Description : In practice, the compression ratio of compression-ignition (CI) engine ranges from (A) 15 to 25 (B) 5 to 10 (C) 40 to 55 (D) 60 to 70

Last Answer : Option A

Description : With increase in __________ Knocking tendency in a spark ignition petrol engine decreases. (A) Supercharging (B) Wall temperature (C) Compression ratio (D) Engine speed

Last Answer : Option D

Description : Air-petrol ratio for maximum power generation in spark ignition engine is about (A) 6 : 1 (B) 12 : 1 (C) 18 : 1

Last Answer : Option B

Description : The violent noises heard in an engine during the process of combustion after the position has passed over the top dead center is known as? 1. Stationary 2. Spark ignition 3. Detonation 4. all of these

Last Answer :     <!-- [endif] -->ans 3

Description : Which of the following is a device used on a tractor or stationary engine for maintaining nearly constant engine speed under varying loads? 1. Volatility of fuel 2. Governor 3. Pre-ignition 4. carburetor

Last Answer : <!-- [if !supportLists] -->1.   <!-- [endif] -->ans 2  

Description : Which of the following types of internal combustion engine is generally used as portable engine for pumping and electricity generation? 1. Spark ignition 2. Stationary 3. Vertical single cylinder 3. all of these

Last Answer : ans 2

Description : If the ignition switch is placed in the ON position and all the engine instruments operate properly except the gas gauge, where would the fault probably be?

Last Answer : Between point (3) and the gas gauge tank unit ground.

Description : Main function of cutout relay in electrical circuit is A. To prevent the reversal of current flow from the battery when dynamo speed (engine speed) reduces. B. To restrict the maximum output at ... deliver current to the battery or to the lightening and ignition circuit. D. None of the above

Last Answer : A. To prevent the reversal of current flow from the battery when dynamo speed (engine speed) reduces.

Description : What is mean by ignition limit? Give ignition limit for SI engine.

Last Answer : Ignition Limit corresponds approximately to that mixture ratio, at lean & rich ends of the scale, where the heat released by spark is no longer sufficient to initiate combustion in the neighboring un-burnt mixture. ... 7:1 to 30:1 Actual Ignition limits for hydrocarbon fuels are 9:1 to 21:1

Description : What is meant by surface ignition in SI engine? 

Last Answer : Surface ignition: Surface ignition is the ignition of the fuel-air mixture by a hot spot on the combustion chamber walls such as on overheated valve or spark plug or glowing combustion Chamber ... and start propagates across the chamber in an analogous manner to what occurs in normal knock.

Description : Explain the effect of the following engine variables on ignition lag and flame propagation: (i) cylinder size (ii) cylinder wall temperature (iii) compression ratio and (iv) inlet air temperature

Last Answer : (i) Cylinder size - Engine of similar design generally run at the same speed. This is achieved by smaller engine having larger RPM and larger engines having smaller RPM. Due to the same ... all reduces the ignition lag. Pre-increase in the intake temperature and pressure increases the flame speed.

Description : Explain the effects of engine variables on ignition lag and flame propagation.

Last Answer : Effect of engine variables on Ignition lag 1) Fuel- it is depend on chemical nature of fuel. The higher, the self-ignition temp of fuel, the longer will be the ignition lag. 2) ... required for flame travel will be about the same irrespective of engine size, provided the engine are similar. 

Description : Can premium diesel be used in any diesel engine?

Last Answer : Premium diesel can be used in most diesel engines, but may not provide any significant performance benefits in engines that are not designed to run on premium fuels.

Description : Can biodiesel be used in any diesel engine?

Last Answer : Biodiesel can be used in most diesel engines, but may require modifications to the engine or fuel system.

Description : Can biodiesel be used in any diesel engine?

Last Answer : Biodiesel can be used in most diesel engines, but may require modifications to the engine or fuel system.

Description : What would be an equal alternative to the diesel engine in transport trucks?

Last Answer : Really, really, really, really, really strong ostriches, a whole team of them would get up enough speed…eventually.

Description : If engine calls for ultra low sulfur diesel fuel, is there damage if you put in higher sulfur diesel?

Last Answer : answer:I don't currently drive a diesel, but I don't believe you can buy low sulfur diesel at fuel stations by highways in the USA. Cold start issues are related to the items below. ... use additives to stop gelling ) 2)moisture in fuel ( separation filters remove and empty accumulated water )

Description : Why didn't GM use a small Diesel instead of a gas engine in the Volt?

Last Answer : answer:Actually diesel currently tends to be more expensive. But I would assume they went with gas because it is your average everyday americans fuel of choice. Plus the engines don't wear ... though if you see volts featuring diesel secondary engines at some point though, especially in Europe.