Diesel engines have always been on the cutting edge of fuel efficiency technology. This advantage has lead Diesel engines to be used in a wide variety of applications, and some of these applications include aquatic applications. Diesel engines can be used to propel ships and boats efficiently to their destination with minimum downtime. The engines can also simultaneously power lighting systems, operate auxiliary equipment, and power communications and navigation equipment.
A diesel engine completes a four stroke cycle to create power. This cycle includes the intake stroke, the compression stroke, the power stroke, and the exhaust stroke. The engine will rotate twice during the duration of these four strokes. diesel engine’s fuel cycle mainly differs from gasoline engines because fuel is supplied at Maximum compression to ignite fuel, whereas a gasoline engine ignites a fuel mixture by spark ignition.
Although modern engine technology has led to increased fuel efficiency; pollutants emitted from cruise ships, cargo ships, and shipping accidents has led to a growing concern for ocean and lake contamination. Cruise ships have been known to create up to 37,000 gallons of Bilge water daily(Howstuffworks), and when the Exxon-Valdez shipwreck occurred an estimation of 11 million gallons of crude oil spilled from the ship polluting 1300 miles of coastline. As an example of Fuel consumption: the Oasis of the Sea cruise ship uses 1 gallon of diesel fuel for every 12 feet of travel through water(Henrichsen).
One configuration of Marine Diesel propulsion is through a Diesel-Electric Propulsion system. This system utilizes “azimuth thrusters (Wartsila)” to replace ship rudders as a more effective way of turning a vessel. Another format of ship propulsion is through a “BUS shaft” which allows ship propulsion even in the case of electric motor failure by means of applying multiple electrically powered motors to power a single shaft (Sam Electronics). Older models and conventional models can also use a transmission drive connected directly to the main power engine.
The Diesel engine operates by utilizing 4 strokes or 2 revolutions to complete its power cycle. On the Intake stroke the intake valve is open, and The piston is travelling in a downward direction ( in relation to crankshaft orientation). The piston’s rings create a tight seal, and during the pistons downward travel create a powerful vacuum that pulls air into the cylinder. On a forced induction engine, a turbocharger or supercharger may be utilized to force pre-pressurized air into the cylinder at this time. Many modern engines use a forced air intake system because it can increase the mass of air that can be placed into a measured volume. Consequently more fuel can be injected into the cylinder because of the increased amount of air in a forced induction system.
The Compression stroke begins when the intake valve closes and the piston starts its upward stroke. It is crucial...