Latvian Maritime academy

using C# coding language for lubricating, cooling and fuel main engine auxiliary systems and ismentioned below with examples for main engine cooling system.Main engine expert diagnostic and evaluation systemMain engine central cooling systemThe central cooling system consists of three lines; a sea water (SW) line, a low temperature (LT)line and a high temperature (HT) line. Main engine cooling water system of ocean-going vessel is basedon three-level-cooling method to cool main engine cylinders. Firstly, high temperature fresh water(HTFW) is used to cool the cylinders; after low temperature fresh water (LTFW) is used to cool theHTFW. Finally, seawater is used to cool the LTFW. HTFW cooling is the most important and the mostcomplicated part in three-level-cooling method because it is related with lots of factors. HTFW systemworking diagram is given in Figure 1.The main devices of main engine HTFW system always consist of cylinders, desalination machineof seawater, remaining steam condenser and main cooler. HTFW brings away partial heat quantity ofmain engine and simultaneously is heated by the main engine cylinder. Then the heated HTFW goesthrough desalination machine and heats the seawater. Afterwards, the HTFW passes through remainingsteam condenser. Finally, HTFW goes into the main cooler and is cooled with LTFW [6].Fresh Water TankFresh Water SupplementCooling WaterPumpMain EngineCylindersSea WaterDesalinationMachine ofSeawaterFresh WaterSteamRemaining SteamCondenserHot WaterHigh Temperature Fresh WaterLow TemperatureFresh WaterMainCoolerLowTemperatureFresh WaterGeneral structure of the systemFigure 1. Structure of main engine HTFW system [6]During the development of the expert system for lubricating, fuel and cooling systems for diagnosisand evaluation, MAN B&W 7S50MC-C main engine is used which, is commonly used in merchant oceangoing ships. This engine has 7 cylinders, 2 strokes, 127 rpm period and has 10.500kW power [7]. The62