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The paper presents the simulation of engine model that was made in AVL Boost Software. The model assumption was the indirect additive supplying hydrogen to the SI engine. The simulation test model of a spark ignition engine, have been developed in the AVL Boost software. The model is based on a real four-cylinder engine, codenamed A14XER that meets the Euro 5 emission standard. This engine is used in passenger vehicles Opel Corsa. In order to most accurate reflection of real engine, the model was developed based on data provided by the engine manufacturer. In the simulation studies two-zone combustion model Vibe (Vibe 2 zone) was used. A General Species Transportation model was also defined, which allowed to use the fuel as a blend of gasoline and hydrogen to supply the engine. Calculations were performed for a full load for different values of rotational speed of the engine crankshaft (from 1000 rpm to 6400 rpm).

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.

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 paper presents the results of the analysis of the simulation tests of the flow of fuel through the fuel rail for the designed radial aircraft engine. A 3D model has been developed for CFD calculations including the fuel rail and elements supplying the fuel to the injectors. Simulation tests were carried out using Star-CD software. The objective of simulation tests has been to determine flow characteristics of the fuel rail design. This design is atypical due to: the shape of the rail - a torus with internal diameter 630 mm, and the fuel flow rate of approximately 30 l/min. Analysis covered flow velocity and pressure at selected points of the design. The tests were conducted for two cases. The first covered constant fuel flow from all injectors; the second covered dynamic states that take place when the injector is opened. The purpose of these tests was to check the possibility of using this solution for prototype purposes.

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 an algorithm of idle speed control of the spark ignition automotive engine by means of spark advance control. The control algorithm is based on a neural network model of the effective torque. The additional load is estimated as effective torque less brake torque on the basis of a linear quadratic model. The additional load is understood as the sum of the alternator brake torque and the momentary and/or permanent changes of the engine's characteristics. The additional load value estimated, the required value of angular acceleration can be determined to make the engine return to the specified speed. This acceleration is achieved by adjusting spark advance. The required value of spark advance is estimated on the basis of the neural network model converse to that of the effective torque. The algorithm was experimentally compared with PID and adaptive algorithms in the same test bed. The tests were conducted under sudden change of external load.

The paper presents the results of analysis of radial piston carburettor engine operation irregularities. The analysis covers indicated pressure and maximum pressure and the angle of its occurrence. Both the values of these parameters at different points of operation of this engine and individual differentiation of individual cylinders in the given points are shown.

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 presents a three-dimensional model of the fuel rail for the purposes of CFD calculations, created by means of the Star-CD system. The model consists of four working sections. The gas flow opening element is a electromagnetically lifted flap. The model was used to calculate gas flow thru each element of the rail, both by continuous outflow and in the case of opening of a particular section. The aim of this part of research was to find parts of the rail critical for its further optimization. The paper summarizes and discusses the results of the calculations and describes the improved design.

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 paper is devoted to the issues of the non-stationary, stochastic analysis of the fuel injection. The aim of the experiment was to obtain data about SI engine operating parameters during operation. The object randomness in sequentially injected combustion engines are investigated. A numerical procedure is designed for the intake manifold mixture preparation to compensate the mixture variations. There are some direct consequences of inherent non-linearities in the basic dynamics of mixture preparation. Compensating for the mixture dynamics (fuel path, air path consisting of intake manifold and wall-wetting dynamics and the oxygen sensor dynamics) performs well only if the statistical properties of the stochastic processes are sufficiently matched. Since this a priori knowledge is hardly accessible in the present case, the authors implemented an experimental procedure.

The paper describes a hybrid air-fuel mixture control system that uses neural network and the direct adaptive algorithm. The A/F ratio stabilization to the stoichiometric value is required to obtain maximum efficiency of the three-way catalytic converter operation. The issues of the algorithm synthesis of the adaptive control of the fuel injection have been formulated. This was supplemented by the presentation of the state-of-the-art in the adaptive control theory as applied to non-stationary random object identification. The control algorithms of the fuel injection have been reviewed and classified. The fuel injection algorithms in the SI engine have been described and differentiated in terms of the used engine model and regulator structure. The algorithms comprise elements of the object modeling as well as adaptive coefficients for the control quality of the air-fuel ratio in the steady and non-steady conditions.

The forced level of permissible vehicle exhaust emissions requires accurate control of the air-fuel ratio. In other words, the amount of air flowing into the cylinder and the fuel quantity must be known accurately. The wall mass of deposited fuel in the manifold of an injection system has a significant effect on fuel maldistribution and the air-fuel ratio excursion. This paper outlines an identification process of a mixture preparation model of the fuel injection in a spark ignition engine. A type of a prototype combustion probe integrated into a spark plug has been developed. This in-cylinder sensor which measures the combustion luminosity is characterized by the good correlation with traditional combustion parameters, including the air-fuel ratio. This paper describes the application of in-cylinder probe in the mixture strength examination. The proposed measure method estimates the fuel mass in a cylinder (where air mass has been constant) as well as the fuel film model parameters.