تاثير عوامل الوسط الخارجي على اداء منظومات تشحين المحركات البحرية

External medium parameters have a major effect on the efficiency of marine power plants performance. Comprehension of the amount of these effect helps to improve the economical and exploitational characteristics of this plants. In this research, this problem had been treated using mathematical modeling method. To achieve that purpose a mathematical model designed representing the performance of marine power plants during navigation in eastern region of Mediterranean. The program had been done by Delphi program, Excel and MathCAD. To confirm the accuracy of results of this mathematical model some experiments had been performed upon Syrian ships plants. According to this study a method of selection and explanation of the suitable working systems for using power plant when external medium parameters changes had been performed. Some related suggestions and recommendations are provided to augment the efficiency of using main power plants that can be used to push ships.