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The intent of this paper is to present a multi-domain and structural study of a hydraulic hybrid machine. The evaluation of different solutions is based on simulation approach, using LMS Imagine.Lab (Amesim) and Ansys Workbench software packages. Amesim provides a 1D simulation suite to model and analyze multi-domain intelligent systems, to predict their multi-disciplinary performance and Ansys Workbench Durability tool performs the high cycle fatigue life calculation. The multi-domain analyses are made for different constructive solutions at different drive ratio. The comprehensive fatigue calculations and results enable engineers to evaluate the main shaft design of the hydraulic motor in order to avoid failures under real world conditions. Some recommendations are made regarding possible solutions.

In this paper is presented the dynamic study on the fuel feeding line of a compression ignition two stroke engine with two cylinders. The common rail type feeding line is working on a pressure of 1600 bar. To provide a uniformity of the fuel dosage introduced in the cylinder and a suitable control of fuel mixture realization a study was made of dynamic phenomenons that occur during the openings and closings of the injectors. The mathematic model was calibrated based on the experiments done on the engine.

The main purpose of this study is to analyze the contact stresses at the interface between the piston-balls and the swash plate of the axial hydrostatic motor, for two constructive solutions. Contact problems are highly nonlinear and required significant resources to solve. In this study, three-dimensional elastic-plastic stress analysis of sliding contact is conducted on 3D piston-swash plate model. The contact pressure distributions are calculated using elastic Hertz theory and finite element method for two constructive solutions. For every solution it was analyzed the influence of the geometric dimensions of the parts in contact.

Internal combustion engines continue to be the vehicles main propulsion system. For all engines, low friction levels are extremely important for the overall efficiency. Components and sub-systems where friction reduction can take place are: crankshaft main bearings, conrod bearings, cam shaft bearings, balancer shafts (if present), auxiliary drives (chains, alternator etc.), valve trains and pistons/pistons ring with liners. This paper describes how the bearings were calculated and assesses motor mechanism friction losses in the engine mechanism.

The objective of the presented research work is the demonstration of the working principle as energy efficient and environmental friendly, low cost vehicle propulsion system of the free piston Stirling principle coupled with the alternant hydraulic transmission in order to use the alternant displacement of the Stirling principle, also to the hydraulic transmission and convert the alternant movement of the liquid using a free wheel based hydraulic motor. The design methodology considers the advantages of efficiency, noise and low emissions of Stirling principle, that can be further improved by a free piston solution and the advantages of a direct alternant energy transfer to the liquid column that is converted in a free wheel based hydraulic motor. An analytical and 1D multi-domain model is used in order to demonstrate the running principle, performance and parameter influences that allow the simulation of the combined Stirling principle with alternant hydraulic transmission integrated on a vehicle. For the heat transfer and flow simulation of the Stirling prime mover, 3D CFD software is used to simulated the temperature distribution. Experimentally the solution was demonstrated on a test rig and integrated on a ATV type demonstration vehicle equipped with the alternant hydraulic propulsion system. Flow, thermal and mechanical parameters are measured to evaluate overall system performance. The former research work of the authors was focused on the demonstration and performance evaluation of the alternant hydraulic propulsion, being demonstrated its efficiency (up to 95 %), adaptability and low mass qualities. Main advantages of the Stirling principle may be improved by using a proper transmission. Coupling also the transmission based on the same alternant principle is a low cost, simple, efficient way to maintain the advantages of the Stirling energy conversion in the same time with an application of the hydraulic transmission that works also alternant in a more efficient way.