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To compete with internal combustion engines fuel cell system must operate and function at least as well as conventional engines. The fuel cell system power properties depends on the air and hydrogen feed, flow and pressure regulation, and heat and water management. Choosing an air flow control method is very important decision that defines many characteristics of the fuel cell system. The air supply method of the cathode side of the fuel cell can contribute to improvement of the system performance. A fuel cell is a stochastic object. Application an adaptive extremum control with bi-parameter identification provide to automatical adjusting the parameters of a controller to the changing characteristics of an object. The aim of control algorithm was air flow control of the fuel cell in order to find and hold the maximal value of net power produced by the fuel cell stack, regardless of changes of the parameters of the object of control and its outer environment.

The paper presents the problem of the influence of sequential injection start angle of LPG gas on the course and the effects of the working process of an IC engine with spark ignition. The research was done on the four-cylinder engine C20LE Holden powered by the evaporated LPG gas with the volatile proportions 50/50 %. The research was carried out in steady state conditions and selected spark advance angles for different injection start angles. The analysis considers parameters which characterize combustion processes (torque, indicated pressure) and the concentration of toxic components in exhaust gases.

The paper addresses the problem of the influence of the LPG injection technique on the course and effects of the SI engine work cycle. Described test-stand experiments were done using SI engine fuelled with simultaneous and sequential injection of vaporized LPG into intake manifold. For both cases of fuelling experiments were done at the same, steady conditions of engine operation. Analyzed engine parameters were: torque, indicated pressure and concentrations of toxic gaseous emissions. These quantities were compared correspondingly for both types of fuelling technique.

The fluctuations in the combustion process of diesel fuel with hydrogen addition in an internal compression ignition engine were investigated. The cyclic combustion pressure was measured and its cyclic oscillations were expressed by indicated mean effective pressure per cycle. The statistical and multifractal analyses applied to the corresponding time series showed considerable changes in the engine dynamics for hydrogen percentages ranging from 5% to 20%. The study for the diesel engine was carried out for 11 various operating points and at the speeds ranging from 1200 to 2000 rpm. Also, exhaust gas components were analyzed. The hydrogen addition was found to affect the differentiation of the indicated mean effective pressure in the engine. A reduction of CO₂ emissions and an increase in NOx emissions were registered.

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.

Nowadays, there is a permanent need to develop alternative fuel production and combustion technologies. The general objective indicated in Directive 2009/28/EC for biofuels in Poland is application in transport 10% of renewable energy by 2020 and 20% by 2030. In Poland, it can be achieved by adding bio-components to liquid fuels. Flexible fuel vehicles are not as popular in Europe as in Brazil, so further ethanol processing is justified. The researched synthetic gasoline was obtained from bioethanol at the Ekobenz Company Ltd. in Poland. In 2008, Sasol launched its 100% synthetic jet fuel produced by CTL (Coal to Liquids). A variety of engine concepts was tested and evaluated in terms of the key criteria for use as a range extender developed by AVL Company. The Wankel engine has been selected for the vehicle prototype as the most compact and of excellent NVH behaviour. The use of this engine in light helicopters is also considered.

This paper examines the possible electric energy collected by the photovoltaic (PV) modules installed on the roof of the bus. The tests were carried out for Mercedes Conecto LF12 buses equipped with CI engine meeting the standards of Euro 5. The research was conducted in the urban contexts/operation. Detailed results of the measurements such as fuel consumption, electric energy consumption, engine speed and vehicle speed are shown. Additional measurements included: the quantity of solar energy coming from the roof of the moving vehicle and electric energy generated from the photovoltaic modules installed. The study was conducted on a city bus taking different routes in the city of Lublin in Eastern Poland. The research bus was supplied with photovoltaic modules and a measurement system.

This paper proposes a fast and simple model of a Compressed Natural Gas indirect injection system to predict the system dynamics with high accuracy for different operating conditions. In a retrofit system the CNG Engine Control Unit (ECU) is able to translate the petrol ECU control strategy in CNG operation. The adaptation of the engine to the natural gas type is handled by using the factory engine control strategy embodied in the factory ECU. The ECU monitors the engine through various sensors and controls its operation using a variety of actuators. Because of many input parameters, the control over the engine becomes quite complex. The use of advanced emission control systems makes such process even more complicated. The new Gas Control Unit is used to reprogram the ECU control parameters to correspond with the use of Natural Gas along with the characteristics of the Natural Gas injectors.