Ad
related to: are diesel engines more efficient
Search results
Results from the WOW.Com Content Network
The most efficient reciprocating steam engine design (per stage) was the uniflow engine, but by the time it appeared steam was being displaced by diesel engines, which were even more efficient and had the advantages of requiring less labor (for coal handling and oiling), being a more dense fuel, and displaced less cargo.
The combined cycle gas turbine (Brayton and Rankine cycle) is a combustion engine that is more efficient than a diesel engine, but due to its mass and dimensions, is unsuitable for many vehicles, including watercraft and some aircraft. The world's largest diesel engines put in service are 14-cylinder, two-stroke marine diesel engines; they ...
However, practical Diesel engines are 30% - 35% more efficient than gasoline engines. [7] This is because, since the fuel is not introduced to the combustion chamber until it is required for ignition, the compression ratio is not limited by the need to avoid knocking, so higher ratios are used than in spark ignition engines.
However, a real diesel engine will be more efficient overall since it will have the ability to operate at higher compression ratios. If a petrol engine were to have the same compression ratio, then knocking (self-ignition) would occur and this would severely reduce the efficiency, whereas in a diesel engine, the self ignition is the desired ...
Hugo Güldner designed what is believed to be the first operational two-stroke diesel engine in 1899, and he convinced MAN, Krupp and Diesel to fund building this engine with ℳ 10,000 each. [2] Güldner's engine had a 175 mm work cylinder, and a 185 mm scavenging cylinder; both had a stroke of 210 mm.
Diesel engines are typically well suited to turbocharging due to two factors: A "lean" air–fuel ratio, caused when the turbocharger supplies excess air into the engine, is not a problem for diesel engines, because the torque control is dependent on the mass of fuel that is injected into the combustion chamber (i.e. air-fuel ratio), rather than the quantity of the air-fuel mixture.
Diesel engines generally achieve greater fuel efficiency than petrol (gasoline) engines. Passenger car diesel engines have energy efficiency of up to 41% but more typically 30%, and petrol engines of up to 37.3%, but more typically 20%. A common margin is 25% more miles per gallon for an efficient turbodiesel.
Actual efficiency can be lower or higher than the engine’s average due to varying operating conditions. In the case of a production gasoline engine, the most efficient BSFC is approximately 225 g/(kW⋅h), which is equivalent to a thermodynamic efficiency of 36%. An iso-BSFC map (fuel island plot) of a diesel engine is shown.
Ad
related to: are diesel engines more efficient