The article presents results of the 3D-CFD modeling of mixture creation process in the cylinder of diesel engine. The simulation was performed using the AVL Fire software. Based on the geometry of the ADCR engine, produced by Andoria-Mot Company, a 3D-CFD model of combustion chamber, channels in the engine head and CNG injector nozzle were created. This model prevented the simulation of the filling, compression and mixture creation process. Specially prepared CNG injector has been placed in the socket of the glow plug, to minimize interference with the structure of the engine. With this solution full functionality of the original fuel supply system was retained with the ability to work with one or two fuels. During studies the location of the gas injector nozzle was changed. The results of simulation are presented for three variants of CNG injector locations. Simulation studies prevented the determination of the degree of stratification and the distribution of fuel in the cylinder of the engine. Influence of the injector nozzle position on the air-fuel stratification in the cylinder was demonstrated. The characteristics of the fuel mass in piston bowl and the rest part of the cylinder were also analyzed. As a result of the simulation, the optimal position of the injector nozzle was presented.

The article presents vibration simulation studies of a crankshaft used in internal combustion engine. The simulation was performed using FEM method. The study was conducted in Abaqus software, and a shaft model was implemented in Catia v5. The influence of a mesh element size on the results of obtained calculations was analysed. A shaft which will be used in the ultralight aircraft engine was the subject of research. Results show the first 10 frequency modes and 12 grid examples for various element sizes, from 9 to 1.3 mm. Moreover, the effect of mesh size on the obtained results is presented. It has been proven that the maximum error for two extreme results (the densest and sparsest grid) is approximately 1.4%; therefore, it is justified to carry out calculations of own vibration on a fatal grid. Results presented herein will be used in the future work on the crankshaft geometry modifications.

The paper presents an analysis of piston thermal loads in an opposed piston engine. The purpose of the work was to check the achieved thermal values of different piston models. Two types of pistons were analysed. The first piston was made entirely of aluminium. The second one was a split piston, made of steel and aluminium. Simulation studies were performed using Abaqus software. Boundary conditions were taken from previously made simulations conducted in AVL Fire software. The wall temperature of the piston was mapped from CFD combustion model. The results of the analyses were illustrated by the distribution of temperature fields on a piston surface. The distribution of temperature fields on the piston surface shows that maximum temperatures are located on sharp edges of a piston bowl, values of maximum temperatures are 402 and 512 °C for aluminium and composed piston respectively.

The paper presents an analysis of the fluid flow in the cooling system of an internal combustion engine with oposite pistons.The purpose of the work was to optimize the flow of fluid through the channels located in the engine block. Simulation studies and subsequent iterations were performed using Ansys Fluent software. Two-equation k-epsilon turbulence model was used in the simulation model. Boundary and initial conditions were taken from previously made simulations conducted in AVL Boost software. The average wall temperature of the cylinder and the temperature of the outer walls of the cylinder were assumed for simulations. The results of the analyzes were graphically illustrated by the speed streamline distribution of velocity fields and temperature.