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The net work produced is also represented by the area enclosed by the cycle on the p–V diagram. The net work is produced per cycle and is also called the useful work, as it can be turned to other useful types of energy and propel a vehicle (kinetic energy) or produce electrical energy. The summation of many such cycles per unit of time is ...
The elevator operator had to regulate the elevator's speed, which typically required a good sense of timing to consistently stop the elevator level with each floor. In addition to their training in operation and safety, department stores later combined the role of operator with greeter and tour guide , announcing product departments, floor by ...
p–V diagram for the ideal diesel cycle. The cycle follows the numbers 1–4 in clockwise direction. Most truck and automotive diesel engines use a cycle reminiscent of a four-stroke cycle, but with temperature increase by compression causing ignition, rather than needing a separate ignition system. This variation is called the diesel cycle.
Both are connected to the shaft with clutches; only one system is driving the ship, in contrast to combined diesel and gas (CODAG) systems that can use the combined power output of both. [1] The advantage of CODOG is a simpler gearing compared to CODAG, but it needs either more powerful or additional gas turbines to achieve the same maximum ...
Low speed diesel engines like the MAN S80ME-C7 have achieved an overall energy conversion efficiency of 54.4%, which is the highest conversion of fuel into power by any single-cycle internal or external combustion engine. [9] [10] [11] Engines in large diesel trucks, buses, and newer diesel cars can achieve peak efficiencies around 45%. [12]
For an example the new CODAG-propelled Fridtjof Nansen-class frigates of the Royal Norwegian Navy, the gear ratio for the diesel engine is changed from about 1:7.7 (engine:propeller) for diesel-only to 1:5.3 when in diesel-and-turbine mode. Some ships even have three different gear ratios for the diesel engines — one each for single-diesel ...
A gearbox and clutches enable either of the engines or both of them together to drive the shaft. Two advantages over simply using a single, larger diesel engine of the same total power output are that (1) diesel engines have somewhat better specific fuel consumption at 75% to 85% max output than they do at only 50% output, and (2) there is a weight and size advantage to using two higher-speed ...
The efficiency of the Diesel cycle is dependent on r and γ like the Otto cycle, and also by the cutoff ratio, r c, which is the ratio of the cylinder volume at the beginning and end of the combustion process: [4] = () The Diesel cycle is less efficient than the Otto cycle when using the same compression ratio.