• VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY

    CHANGE OF EXERGY MOTION IN THE MARINE STEAM PLANT WITH MAIN SHAFT SPEED VARIATION

    Trans Motauto World, Vol. 2 (2017), Issue 4, pg(s) 174-177

    Exergy flow motion insight and analysis of plant requirements for a typical conventional LNG carrier with Rankine regenerative feed water heating steam cycle is given in this paper to clarify and distinguish auxiliary flow streams from the useful ones. Auxiliary flow supports the plant operation, but reduces exergy efficiency by certain amounts. Main boilers exergy flow streams are divided into two major groups: superheated and de-superheated flow stream consumers. A plant run test was carried out by varying main shaft revolutions to collect required thermodynamic data at various plant locations. In the presented marine steam plant is explained exergy flow streams for considering components and flow streams ratios of particular plant components. It is detected and explained the points of excessive auxiliary stream flows consumption and recommendations for possible reduction in saving auxiliary power or steam consumption are given.

  • VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY

    MONITORING OF CHANGE IN VOLUMES FOR DIESEL ENGINE IN-CYLINDER PROCESS WITH QUASI-DIMENSIONAL NUMERICAL MODEL

    Trans Motauto World, Vol. 2 (2017), Issue 3, pg(s) 124-127

    Distribution of volumes and their change in the diesel engine cylinder is an essential parameter of each numerical model. Quasidimensional numerical model divide space inside the engine cylinder into two main areas: fuel spray packages and a large surrounding area without combustion, which is used for air distribution into the fuel spray packages. This paper analyzes the four-stroke diesel engine for thelight truck drive in several operating modes. Numerical model is validated by using laboratory measurements. In a selected engine operating mode are presented the results of a numerical model for the observed volumes inside the engine cylinder. The observed volume change provides insight into the details of the air-fuel mixing process and fuel evaporation. Described changes are the basis for the calculation of heat-release and pressure changes in the cylinder. The developed numerical model provides insight into the details of the process inside the engine cylinder which cannot be measured with standard measuring equipment.