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According to the information provided by the catalyst producer, the catalyst with the trade name Reduxco, which was used in the research, is a reaction product of acetic acid, iron, n-butanol, n-propanol and isopropanol. According to Customer data, Reduxco catalyst in a fuel causes a decrease of the energy of activation of the hydrocarbon fuel oxidation reaction, introduces additional OH groups allowing to increase the burning rate, facilitates the combustion of already formed solid particles in the engine cylinder. To confirm this information, comparative tests were carried out (in the Internal Combustion Engines laboratory of the Cracow University of Technology); the analysis included not only the energy parameters and exhaust gas composition of the diesel engine powered by standard diesel oil and Reduxco-containing fuel, but also the indicator charts and rate of heat release in the engine cylinder.

This article presents the results of an analysis of the yaw marks left by a car with normal pressure in all tires and then normal pressure in three tires and zero in one rear tire. The analysis is a continuation of research on influence of reduced tire pressure on car lateral dynamics in a passing maneuver, discussed in the SAE paper No. 2014-01-0466. Preliminary analysis of yaw marks has shown, that a wheel with zero pressure deposits a yaw mark whose geometry differs from the yaw mark made by a wheel with normal pressure based on which we could calculate: critical speed, slip angle and longitudinal wheel slip. The aim of the presented research was to analyze the yaw marks left by car with zero pressure in one rear wheel in order to check the possibility of determining the vehicle critical speed, slip angle and longitudinal wheel slip. It was reached by performing bench and road tests during which the vehicle motion parameters were recorded using GPS Data Logging System.

The paper presents a modeling and simulation of the pneumatic injection process of a fuel mixture and exhaust gases in two-cylinder two-stroke SI engine. The fuel is injected to the small chamber between two cylinders which is connected with combustion chambers of both cylinders by duct and gas flow is controlled by a valve. The pneumatic injection system enables the reduction mostly of the hydrocarbons by controlling of the valve opening and fuelling phase. The paper presents the mathematical zero-dimensional model of the fuel evaporation in the mixing chamber and 1-dimensional model of the unsteady multi-phase charge between the cylinders. The mathematical model takes into account also the thermodynamic processes taking place in the cylinders. The paper performs the engine parameters for different engine configurations and calibrations obtained from simulation. This is the initial development step of such engine, which was designed and recently made and will be tested by the author.

The authors measure and simulate the vehicle motion in situations where typical defensive maneuvers in road traffic are being carried out, namely straight braking, double lane-change (overtaking), and ramp input on the steering wheel. They reproduce the vehicle motion (i.e. velocity, vehicle's C.G. trajectory and yaw angle) by using real records or by the simulated electronic data recorder (EDR) outputs. Thus, they operate in a way that is similar to that employed by forensic experts who analyze the EDR outputs. The employed method provides means of comparing the real or simulated exact values of velocity and of the vehicle's C.G. trajectory to the readings obtained by integrating the EDR outputs simulation. Estimation of the error, produced by the expert employing the EDR outputs, can be made in this way. The results show a possibility of occurrence of significant values of the error for simplified version of the device.

The paper gives a short description of a rich mixture injection system (RMIS) with an additional mixing chamber shown in the enclosed Fig. 26. A mathematical model of air-fuel charge exchange with vaporization of fuel in the chamber is presented. The paper includes the results of thermodynamic parameters in the cylinder and the chamber taken from measurements and calculations. The main work was carried out to determine the influence of control parameters of the pneumatic valves for two filling systems of the mixing chamber on CO, HC and CO2 emission. Calculations were done by using of a modified code of the KIVA3V program and a specially written computer program. The program was based on a zero- and one-dimensional model of engine work cycles, unsteady gas flows and emission of exhaust gas. The paper presents possibilities of toxic exhaust gas components reduction and decrease of fuel consumption in RMIS engine in comparison to the standard engine.

Paper includes a description of a two-stroke engine with a rich mixture injection system. The injection of the fuel mixture follows from an additional chamber as a result of pressure difference between the chamber and the cylinder. Formation of the fuel mixture both in the chamber and in the cylinder is described by a simple mathematical model. The fuelling system of the engine was analysed both by use of zero-dimensional model and 3-dimensional model on the base of modified KIVA program. The results were compared with that obtained from the simple computer program based on given mathematical equations and experimental tests on real engines. A diagram of the fuelling system explains a principle of work and enclosed figures show variation of pressure and temperature in the chamber, vaporisation of fuel during crankshaft rotation and visualisation of the mixture injection to the cylinder at different engine speeds.

Recently in order to decrease of the exhaust emission and fuel consumption in the modern small SI two-stroke engines a direct fuel injection is applied or a rich fuel mixture is delivered directly to the cylinder. In order to increase the time required to vaporize all injected fuel and create a stratified charge with the rich mixture near the spark plug, a new concept of preparation and injection of the fuel mixture was analysed and tested. This paper includes a short description of the system shown in enclosed figures, the mathematical model of the charge exchange in the chamber and the cylinder and also the model of fuel vaporization in the chamber. The main aim of the paper was a comparison of the thermodynamic parameters especially the emission of CO, HC and CO2 obtained from experimental tests and from a simulation process in KIVA program for the standard carburetted engine and the engine with proposed system at some rotational speeds and control configurations.

The paper concerns to the filling efficiency in spark ignition two-stroke engines of small power with loop-scavenged system. Amount of lost fresh charge to exhaust system has been presented. By changing of geometrical dimensions of transfer and exhaust ports scavenge efficiency, delivery ratio and exhaust loss of fresh charge can be changed. Full analysis of mass flow rate of air-fuel mixture and exhaust gases was conducted. Comparison of velocity vectors in an opened cylinder by means of finite element method in a CFD-program and during measurement is shown in graphs. There was obtained a big conformity of results from experimental research and calculation, which allowed carrying out the spatial analysis of fresh charge distribution in the cylinder in dependence on shape of combustion chamber. Principally geometry of ports and combustion chamber influence on emission of unburned hydrocarbons in exhaust system.

The future of new brake systems is very promising. Development of design, materials, technology and control solutions provides opportunity to improve brake system performance. However, knowledge of friction processes still does not answer all current problems. This paper presents a review of factors influencing brake disc - brake pad operating conditions. Attention is focused on synergism of factors and changes in mating surfaces. The authors took into consideration factors coming from operation of the whole brake system: from master cylinder to friction couple. The analysis is supported by the unpublished research results in this field.

Paper includes a description of the new system of rich mixture injection by applying of additional chamber and gas flow controlled by electronic valves. The system enables decreasing of hydrocarbons emission and specific fuel consumption. The paper includes mathematical model of exchange charge in the chamber and cylinder, injection process, simulation results of physical processes, which occur in the cylinder and chamber. A diagram of the fuelling system explains a principle of work and figures show variation of gas pressure, temperature and vaporization of fuel during crankshaft rotation. The system is designed for one-cylinder two-stroke engine, but can be applied also for multi-cylinder engines.