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Which of the following actions will help to reduce the black smoke emission of a diesel engine? 1. Run at lower load, i.e. derating 2. Have regular maintenance of the diesel engine, particularly of injection system 3. Use diesel oil of higher cetane number Select the correct answer using the code given below.

Which of the following actions will help to reduce the black smoke emission of a diesel engine? 1. Run at lower load, i.e. derating 2. Have regular maintenance of the diesel engine, particularly of injection system 3. Use diesel oil of higher cetane number Select the correct answer using the code given below. Correct Answer 1, 2 and 3

Black smoke at the exit of the diesel engine is due to the soot component of the diesel, particulate matter. Under normal operating conditions, this soot is oxidized in the cylinder and is not visible. The visible black smoke is generally due to injecting too much fuel for the amount of air available in the cylinder or due to poor mixing between fuel and air. This black smoke emission can be avoided by the proper design and maintenance of the injection system.

Cetane Number: Centane number is the measure of the fuel's ignition capacity under the combustion chamber temperature and pressure conditions. Cetane number is determined by comparing its ignition quality with the blend of two standard reference fuels, the straight-chain-paraffin n-cetane which ignites very quickly and a branched paraffin heptamethyl nonane which has a long ignition delay. Higher cetane number fuel is associated with improved combustion, improved emissions. Black smoke emission increases with lower cetane number fuels especially when it is below 45. 

Derating: Derating of the engine means a reduction in power output compared to the most efficient power output, to match the ambient air conditions. Derating reduces the power output, therefore, there will be a lean mixture of fuel and air, the combustion of fuel will be proper and there will be lesser black smoke emissions. 

Related Questions

In Diesel engines, the control of black smoke in the exhaust can be achieved by: 1) Running the engine at lower load. 2) Maintaining the injection system perfect. 3) Using Diesel fuel of higher Cetane number. Which of the above statements are correct?
In Diesel engines, the control of black smoke in the exhaust can be achieved by:
1. Running the engine at lower load.
2. Maintaining the injection system perfect.
3. Using Diesel fuel of higher Cetane number.
Which of the above statements are correct?
In the question below, are given a statement followed by three courses of actions numbered I, II and III. On the basis of the information given, you have to assume everything in the statement to be true, and then decide which of the following suggested courses of actions logically follow(s) for pursuing. Statement: High-sulphur fuel oil (HSFO), essentially the leftovers of an oil refiner's output, will still flow from refineries around the world even after new rules start up in 2020 curtailing its use in the global shipping fleet.Sixty percent of the 33 refineries in a global survey will still produce HSFO in 2020 although the supply will tighten as 70 percent of these refiners plan to reduce their output.  Courses of action: I. Starting that year, ships will use marine fuel, which primarily consists of residual fuel oil, with a maximum sulphur content of 0.5 percent under International Maritime Organization (IMO) rules to reduce air pollution.  II. Currently, the global shipping fleet, which includes oil and chemical tankers as well as container ships, uses as much as 3.3 million barrels per day of HSFO with a maximum of 3.5 percent sulphur.  III. Refiners will have little incentive to produce HSFO after the regulations though some demand will remain as a small but growing number of vessels are fitted with smokestack scrubbers that remove the sulphur from the exhaust fumes and power plants will continue to consume the fuel. 
All things which have smoke have fire; This hill has smoke; Therefore, The hill has smoke; and No non-fiery things have a smoke; This hill has smoke; Therefore, this hill is non-fiery The above is an example of which type of inference in Indian logic?
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilization is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The theme of the passage is
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilization is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. Biomass is an energy source used in
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The synonym for Ubiquitous is
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The energy sources of the future are
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Modern civilisation is completely dependent on energy, which has therefore to be abundant and also economical. About 85% of the world's energy is supplied by oil, coal and natural gas while nuclear, hydro, wind and solar power and biomass supply the rest. Coal, nuclear and hydro are used primarily to generate electricity while natural gas is widely used for heating. Biomass is used both for heating and cooking. The wind and solar power is the future's hope as they are sustainable energy sources. Oil powers almost all machines that move and that makes oil uniquely versatile. Oil powered airplanes carry 500 people across the widest oceans at nearly the speed of sound. Oil powered machines produce and transport food. Oil powered machines are ubiquitous. Clearly, we live in the age of oil but it is drawing to a close. According to data available if oil production remains constant until it's gone, there is enough to last 42 years. Oil wells will produce less as they become depleted, which will make it impossible to keep production constant. Similarly natural gas and coal will last another 61 years and 133 years respectively. Naturally, as they become scarce, they become expensive, leading to a worldwide energy crisis. If we are to survive on this planet, we have to make a transition to sustainable energy sources. The transition may be willy-nilly or planned - the choice is ours. The dawning era of limited and expensive energy will be very difficult for everyone on earth but will be even more difficult if it is not anticipated. It is of utmost importance that the public and policymakers understand the global energy crisis and act in tandem to ensure that the species 'homo sapiens' does not become extinct. The survival of mankind will depend on
In the question below, are given a statement followed by three courses of actions numbered I, II and III. On the basis of the information given, you have to assume everything in the statement to be true, and then decide which of the following suggested courses of actions logically follow(s) for pursuing. Statement: Starting October, all new cars will have pedestrian safety features, including new design of the bonnet, to reduce impact on pedestrians during accidents. Advanced safety features are needed in all vehicles in India as vehicle safety cannot be confined to luxury vehicles only. Around 1.5 lakh people are killed in road accidents every year in the country, nearly 60% of them are pedestrians.  Courses of action: I. The government has set a target to reduce the number of road deaths by half in the next two years. The ministry of road transport and highways has been issuing new safety standards for the automobiles along with eliminating the black spots on national highways.  II. By next month, all new cars will have pedestrian safety feature, including new design of the bonnet, to reduce impact on pedestrians during accidents.  III. Ministry of road transport and Highways is planning to implement all safety features in vehicles with active support of vehicle manufacturers. Electronic stability control (ESC) and autonomous emergency braking (AEB) will be incorporated in new vehicles by 2022.