The compression of air in a diesel engine is

1 Answer

Answer :

4:1 to 25:1.

Related questions

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 : 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 : In diesel engine, the compression ratio as compared with the expansion ratio is a. same b. less c. more d. variable

Last Answer : ANSWER c. more

Description : The tendency of a diesel engine to knock increases if a. engine speed is increased b. engine power is increased c. cetane number of the fuel is increased d. compression ratio is increased

Last Answer : ANSWER d. compression ratio is increased

Description : For the same capacity engines, the compression ratio of diesel engine a. is lower than the compression ratio of SI engine b. is higher than the compression ratio of SI engine c. is same as the compression ratio of SI engine d. cannot say

Last Answer : ANSWER b. is higher than the compression ratio of SI engine

Description : For same compression ratio a. Diesel cycle has lower efficiency than Otto cycle b. Diesel cycle has higher efficiency than Otto cycle c. Diesel cycle and Otto cycle have equal efficiencies d. Depends upon the load on engine

Last Answer : Answer a. Diesel cycle has lower efficiency than Otto cycle

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 : The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be (A) More (B) Less (C) Same (D) Data insufficient to predict

Last Answer : (A) More

Description : Pick out the correct statement. (A) Compression ratio of an Otto engine is comparatively higher than a diesel engine (B) Efficiency of an Otto engine is higher than that of a diesel ... Diesel engine normally operates at lower compression ratio than an Otto engine for an equal output of work

Last Answer : (B) Efficiency of an Otto engine is higher than that of a diesel engine for the same compression ratio

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 : Compression pressure in diesel engine cylinder is a) 6-10 kg/cm2 b) 10-20 kg/cm2 c) 20-35 kg/cm2 d) None of the above

Last Answer : c) 20-35 kg/cm2

Description : Air standard Otto cycle is more efficient than the diesel cycle for the same (A) Heat addition & compression ratio (B) Heat addition & pressure (C) Compression ratio & pressure (D) Cylinder dimension & rpm

Last Answer : (A) Heat addition & compression ratio

Description : Why is air compressed in a diesel engine?

Last Answer : In a diesel engine, filtered air enters the cylinder and gets compressed to generate enough heat to ignite the diesel.

Description : In a naturally aspirated diesel engine, the air is supplied by a A. supercharger B. centrifugal pump C. movement of engine piston D. reciprocating pump

Last Answer : ANSWER : C

Description : In diesel engine the fuel injected would burn instantaneously at about compressed air temperature of A. 1000°C B. 250°C C. 450°C D. 2000°C

Last Answer : ANSWER : A

Description : Which of the following is compressed in a diesel engine cylinder A. air B. fuel C. air and fuel D. air and lub oil

Last Answer : ANSWER : A

Description : The output of a diesel engine can be increased without increasing the engine speed or size in the following way A. feeding more fuel B. increasing the flywheel size C. heating intake air D. supercharging

Last Answer : ANSWER : D

Description : If the performance of diesel engine of different sizes, cylinder dimensions and power rating are to be compared, which of the following parameters can be used for such comparison? (a) Swept volume (b) Air fuel ratio (c) Specific brake fuel consumption (d) Volumetric efficiency

Last Answer : Ans :c

Description : In a 4 S diesel engine, the term ‘squish’ refers to the (a) Injection of fuel in the precombustion chamber (b) Discharge of gases from the precombustion chamber (c) Entry of air into the combustion chamber (d) Stripping of fuel from the core

Last Answer : Ans :c

Description : Keeping other parameters constant brake power of diesel engine can be increased by (a) Decreasing the density of intake air (b) Increasing the temperature of intake air (c) Increasing the pressure of intake air (d) Decreasing the pressure of intake air

Last Answer : Ans : c

Description : Mixing of air and fuel in the diesel engine occurs in a. injection pump b. carburetor c. engine cylinder d. inlet manifold

Last Answer : ANSWER c. engine cylinder

Description : Which of the following medium is compressed in a diesel engine cylinder? a. air b. air and fuel c. air and lubricating oil d. fuel

Last Answer : ANSWER a. air

Description : Scavenging air in diesel engine means a. air used for combustion under pressure b. forced air for cooling the cylinder c. burnt air containing products of combustion d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke

Last Answer : ANSWER d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke

Description : In diesel engine, the fuel is ignited by a. spark b. injected fuel c. heat resulting from compressing air that is supplied for combustion d. ignitor

Last Answer : ANSWER c. heat resulting from compressing air that is supplied for combustion

Description : In a diesel engine the high temperature needed to ignite the fuel is achieved by – (1) using heat from exhaust (2) the battery (3) compressing air in the cylinders (4) an electrical spark

Last Answer : (3) compressing air in the cylinders Explanation: Diesel engines use the heat of compressed air to ignite the fuel (intakes air, compresses it, then injects fuel). Diesel engines need high compression ratios to generate the high temperatures required for fuel auto ignition.

Description : What are the uses of air filter and superchargers in diesel engine power plant?

Last Answer : The purpose of air filter is to filter the air from dust and other suspended particles. The purpose of super charger is to increase the pressure of the engine to increase power of the engine.

Description : What Are The Uses Of Air Filter And Superchargers In Diesel Engine Power Plant?

Last Answer : The purpose of air filter is to filter the air from dust and other suspended particles. The purpose of super charger is to increase the pressure of the engine to increase power of the engine.

Description : In a diesel engine the high temperature needed to ignite the fuel is achieved by (1) using heat from exhaust (2) the battery (3) compressing air in the cylinders (4) an electrical spark

Last Answer : compressing air in the cylinders

Description : State the functions of following elements: i) Diesel engine system ii) Air intake system iii) Engine exhaust system iv) Engine starting system.

Last Answer : i) Diesel engine system:-  Four strokes Two strokes ii) Air intake system:- Air intake system is provided to supply air to engine cylinder for fuel combustion.  iii) Engine exhaust system ... provided to rotate the engine initially until the firing starts and engine run under its own power. 

Description : In four stroke engine which of the following is also known as power stroke a. Suction stroke b. Compression stroke c. Expansion stroke d. Exhaust stroke (Ans:c) Measurements of fuel and air ... into IC engine,___________its efficiency A. increase B. decrease C. does not alter D. unpredictable on

Last Answer : ANSWER : B

Description : In _____________ injection system only one pump is sufficient for multi-cylinder engine. a) air b) mechanical c) compression fuel d) common rail

Last Answer : Answer: d Explanation: None.

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 : Which of the following has the minimum value of COP for a given refrigeration effect? (A) Reverse Carnot cycle (B) Ordinary vapour-compression cycle (C) Vapour-compression process with a reversible expansion engine (D) Air refrigeration cycle

Last Answer : (D) Air refrigeration cycle

Description : Out of the following refrigeration cycles, which one has the minimum COP (Co-efficient of performance)? (A) Air cycle (B) Carnot cycle (C) Ordinary vapour compression cycle (D) Vapour compression with a reversible expansion engine

Last Answer : A) Air cycle

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 : Most high-speed compression engines operate on a. diesel cycle b. Otto cycle c. dual cycle d. Carnot cycle

Last Answer : ANSWER c. dual cycle

Description : The thermal efficiency of a diesel cycle having fixed compression ratio with increase in cut-off ratio will a. increase b. decrease c. independent d. increase or decrease depending upon other factors

Last Answer : ANSWER b. decrease

Description : For same compression ratio and heat input a. Otto cycle is more efficient b. Diesel cycle is more efficient c. Both are equally efficient d. None of the above

Last Answer : ANSWER a. Otto cycle is more efficient

Description : The efficiency of Diesel cycle depends upon  A. temperature limits  B. pressure ratio  C. compression ratio  D. cut-off ratio and compression ratio

Last Answer : Answer: D

Description : Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle  A. combustion is at constant volume  B. expansion and compression are isentropic  C. maximum temperature is higher  D. heat rejection is lower

Last Answer : Answer: D

Description : The compression ratio for Diesel engines is  A. 3 to 6  B. 5 to 8  C. 15 to 20  D. 20 to 30

Last Answer : Answer: C

Description : For same compression ratio and for same heat added  (a) Otto cycle is more efficient than Diesel cycle  (b) Diesel cycle is more efficient than Otto cycle  (c) efficiency depends on other factors  (d) both Otto and Diesel cycles are equally efficient  (e) none of the above.

Last Answer : Answer : a

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 : The part that is not needed in a diesel engine is

Last Answer : sparkplug/carburettor.

Description : The basis of diesel/petrol engine is Chemical change of

Last Answer : liquid when under goes

Description : List the differences between petrol engine and diesel engine.

Last Answer : Petrol Engine 1. Petrol vapour is used as fuel 2. Petrol engines are spark ignition engines. It requires a spark plug. 3. Cost of petrol is comparatively high. 4. Expansion of gaseous products with ... 6. Compression of air is in the ratio 4:1 to 25:1 4. Expansion against constant pressure.

Description : Mention the uses of diesel engine.

Last Answer : Diesel engines are used a) in transport vehiclesb) in generators to produce electricity d) by some sugarcane juice vendors to crush sugarcane.d) by cement concrete mixers

Description : Why there is not sparkplug in a diesel engine?

Last Answer : The compression of air in the cylinder is 4:1 to 25:1. This compression increases the temperature to around 1000K which is enough to ignite diesel. In the ignition stroke, a required amount of diesel is injected. Hence no sparkplug is needed.

Description : Briefly explain the working of a diesel engine.

Last Answer : Construction: A diesel engine consists of an airtight piston fitted inside a cylinder. The piston is free to move inside the cylinder. The cylinder has two valves - an inlet valve and an outlet ... there is an injunction pump. Working: The working of diesel engine consists of five strokes.

Description : Explain the principle of working of a diesel or petrol engine.

Last Answer : Chemical change of liquid fuels like petrol or diesel when under goes combustion produces large volume of gases and exerts pressure. This is the basis of working of petrol or diesel engine.