Grzegorz Boruta

METHODS OF VERIFICATION OF MAIN TRANSMISSION GEAR BOXES ON TEST BENCH USING VIBRATION MEASUREMENT

The methodology of research and the inspection of the main transmission gearboxes of multi axles armoured vehicle ROSOMAK under operating conditions are described in this article. Tests are carried out on the bench to allow force transmission changes to the extent similar to the loads that occur during vehicle operation. Transmission gear boxes are driven by an internal combustion engine 359 through a reducer (standard engine gearbox). This reducer increase torque and decrease shaft speed similar to condition in the vehicle. On the other side of the transmission, multiplying gearbox coupled with a brake dynamometer were placed. It increases speed according to requirements of the work field of the dynamometer W-230. The combustion engine made possible to measure vibration of transmission gearboxes under the high torque. The torque is greater than obtainable by using electric motors. The value of the inertia moment loading axle shaft was determined using a simplified kinematic diagram. During the tests, vibration were measured at selected points of the housing using different methods of attachment of vibration transducers. First, the screw for assembling the vibration sensor was glued to the hull of gearbox. Second, the sensor was connected with gearbox by permanent magnets. Third, the sensor was used as a hand probe. The results of vibration measured by these methods were compared. Temperature of the gearbox was also measured by using thermocouples and thermovision methods. Selected results are presented and analysed of vibration transmission and its temperature at selected working conditions.

POSSIBILITIES OF APPLICATIONS OF STIRLING ENGINE IN COGENERATION SYSTEMS

This study takes into account engines working in Stirling cycles in cogeneration systems. Stirling engines have been selected because of their characteristics of exploitation. The possibility of their use in cogeneration systems is more favourable in comparison with other combustion engines because they can avoid usage of industrial and transport fuels. The Stirling engines enable the use of biomass, agricultural and other waste energy sources in micro tri- and cogeneration plants dedicated for the use in agriculture and forestry. Considering such applications, three types of usage structures of Stirling engines are proposed. All three structures are dedicated to install in small residential or farm buildings. These three types of structure are named: “type master”, “type slave” and “type customer”. In accordance with the proposed structures, different types of engine constructions are discussed, too. At the same time, the authors described the dependences between Stirling engines and electric power energy systems. The arguments of grid power systems and dispersed energy resource in text were reviewed. After that overview, some legal problems are discussed. Finally, the conception of independent dispersed micro agropower system and some technical equipment were described. Technical realization of the proposed conception requires: proper type, installation and usage of Stirling engines and proper expectations of achieved results.

THE IMPACT OF THE SHARE OF BIOGAS IN A SUPPLY DOSE ON LOAD PARAMETERS IN THE COMBUSTION CHAMBER OF A DUAL-FUEL COMPRESSION-IGNITION ENGINE

The need to increase the share of renewable fuels in the general energy balance necessitates the search for new possibilities of their use. One such fuel is biogas, which is generated both as a result of natural processes occurring, e.g. in landfills, and can also be obtained from various biological materials in biogas plants. Because of its properties, biogas may be used to power spark-ignition engines. At the same time, in numerous scientific centres attempts are underway at using biogas to power compression-ignition engines. Due to the relatively high autoignition temperature of methane, which is the main component of biogas, it is necessary to use dual-fuel supply systems in CI engines. Providing fuel gas to such an engine in the form of biogas, which can have a varying chemical composition, considerably changes the conditions of combustion in the engine compartment, which affects both the performance of the engine as well as the emission of toxic compounds into the atmosphere. The present paper discusses the impact of supplying an engine with fuel gas, as well as of the composition of biogas, on the ratios describing the load in the combustion chamber of a dual-fuel compression-ignition engine. The calculations were conducted for a four-cylinder forced induction engine, assuming that the volume of the drawn gas and air mixture equals the volume of the drawn air during mono-fuel operation.

TEST STAND FOR A COMBINED HEAT AND POWER UNIT FED WITH ALTERNATIVE GAS FUELS

This paper presents the reasons for the development of gas-combined power and heat units and justification for testing the effect of the used gas fuel on the performance of such units. A PBCHP10VB CHP unit driven by a liquidcooled piston combustion engine adapted for feeding with gas fuels is described. The concept is presented for testing the effect of different gas fuel mixtures, including biogas, on this unit’s operation, mainly on the obtained electric power from the current generator and the temperature of the liquid cooling the driving engine heating up output water and on the composition of exhaust gas from this engine. A simple device for obtaining gas fuels containing different combustible gas mixtures is presented. The instruments used to check the composition of the obtained gas fuel and check exhaust gas from the engine are briefly described. The paper describes a test stand for testing the effect of different gas fuels on the operation of a PBCHP10VB gas CHP unit manufactured by Power Blessed Co., Ltd registered in Shanghai, constructed at the Department of Mechatronics and Technical and Information Technology Education of the Faculty of Technical Sciences at the University of Warmia and Mazury in Olsztyn.

Preliminary tests on a combined heat and power unit fed with gas fuels

This paper presents a model unit demonstrating the possibility of using a PBCHP10VB CHP unit driven by a piston combustion engine fed with gas fuels for heat and power cogeneration. A mobile unit available in the Department enables heat and power cogeneration at any place with available gas fuel, e.g. compressed in a pressure tank or from a production and transmission system. A radiator is connected to the unit’s heat connection for demonstrative purposes – this is the simplest model of a network using the heat generated by the unit, with the possibility of easy connection to another network for heating rooms and/or tap water instead of this radiator. Any three-phase load (e.g. a single phase converter) can be connected to the unit’s power connection. A constructed mobile power generator fed with alternative gas fuels (e.g. biogas) is described which can be used in the field in a biogas system for power generation with simultaneous heat recovery. The results of the first preliminary tests on the effect of the type of gas fuel used on the obtained electrical and thermal power and on the composition of exhaust gas from the driving combustion engine are presented. A plan for further tests is also outlined.

A comparison of selected operating parameters of the diesel engine fuelled with mixtures of diesel oil or liquid bio - fuel and natural gas for low - power generators

Following the modern fuel market, one can notice that prices of liquid petroleum derivatives – petrol and diesel oil – which most often fuel piston internal combustion engines are increasingly higher. Similarly, the price of petroleum-derivative gas (LPG – the liquefied petroleum gas – simply speaking, a mixture of propane and butane) is also growing. Many academic and industrial institutions of science conduct research to determine whether it is possible to replace liquid petroleum-derivative fuels with some other potentially cheaper ones. It would also be beneficial if these new fuels were more “ecological” – so that their combustion products would not be harmful for the environment and if they were produced with the use of plants. Fuel stations commonly offer a fuel for diesel engines which is a mixture of fatty acids methyl esters (FAMEs) from vegetable oils, in Poland for instance from rape seeds. The paper presents a comparison of selected operating parameters of the Hatz 1B40 engine fuelled with mixtures of diesel oil or liquid bio-fuel and natural gas. Indicator diagrams, exhaust gases composition and vibration signals recorded on the engine body were analyzed. The study was conducted on the Hatz 1B40 diesel engine which is used among others in FOGO power generator sets, after replacing the original feeding system by common rail system for liquid fuels and after adding natural gas feeding system.