14. starptautiskā konference 2012 - Latvijas Jūras akadēmija

Proceedings of 14th International conference „Maritime Transport and Infrastructure - 2012”Using formulas (1)… (5) calculate starting time duration t i (till moment when crankshaftachieves 1/3 from nominal RPM i.e. 4 s -1 , the consumption of air Q i at i starting time and the pressurein starting air receiver p oi at i time starting beginning at different compression pressures in cylinder p c( 8,5 MPa and 9,5 MPa ). Starting air receiver's volume V rec = 4 m 3 . The starting air supply suspensionis 65 degree of crankshaft rotation angle in relation to TDCThe results of calculations are shown diagrammatically in figure 1.ConclusionsThe paper offers a simplified calculation method of starting and reversing processes.The key starting and reversing parameters of an engine may be determined, from the cylindercompression pressure and the starting air pressure, without complex calculations. The parameterswhich may be determined, in this way, are: The engine starting time duration; the number ofcrankshaft revolutions needed for starting; the air supply suspension angle; the air receiver’s volumefor the required minimum 12 starts and the air consumption during starting.The method can be useful for marine engineers, also for ship designers, for evaluation indesigning new or redesigning existing propulsion systems.References1. Возницкий И. В. Судовые двигатели внутреннего сгорания. Моркнига Санкт. Петербург. 20072. Doug Woodyard Pounder, s Marine Diesel engines and gas turbines. 2004 Elsevier ltd.3. LPG tanker „Kurzeme” Main engine arrangement.67