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Abstract

The article presents vibration test of three different types of gyroplane main rotors. The test was carried out on a specially prepared test bench using a Red Led Tacho Sensor measuring system. Tests were conducted for the project „Research and development works on innovative construction of aircrafts of weight over 560 kilograms at the company Trendak Aviation”. The work outlines the basic properties of the gyroplane vibration and gives their sources. The research focused on the gyroplane main rotor vibration related inter alia to the rotor imbalance as well as rotor hub connector construction. Tested rotors consisted of three different types of gyroplane rotor blades and innovative universal hub connector with positive coning angle of 2.8º. The article summarized the basic properties of three types of gyroplane the rotor blade, marks advantages of use hub connector witch constructional dihedral angle. Discusses the principle of operation of measuring device, tests methodology starting from instrument calibration. The results of the measurements are shown in the graphs in polar coordinates. The vibration measurement is carried out in two axes, in x-axis, longitudinal, along the rotor radius and in y-axis, perpendicular to the x-axis, in the direction of the chord of the rotor blades.

Abstract

Thrust vector control systems of propulsion systems of dynamic positioning vessels are commonly applied on vessels with DP2 and DP3 class of DP. It was submitted the ways of providing information to dynamic positioning operator DPO about detecting of suspicion of failure in specific thruster and shown the ways of response in such situations. In the case of failure and shut down one of working thrusters, it must be done the possibility assessment of continuation of DP system safe operation. If such situation is not possible, it should be considered the work of DP system on limitations. It was indicated on safety threats during operation of DP systems resulting from system failure or even the design faults. It commonly applies the failure mode and effect analysis (FMEA or FMECA) from the design phase through sea trials until to the verification process during operation. It allows the elimination of majority of faults in the DP systems. It was communicated the basic conditions of safe operation of vessels with DP systems and the examples of conditions which releasing the readiness signal of DP propulsion system elements. Observed development of control and automatics systems will result in increasing the safety of DP systems operation.

Abstract

For the third time in the history of humankind, it is trying to implement e-mobility. There is a reasonable hope that this attempt will succeed this time. E-mobility is generally regarded as a zero emission. This sentence can only be true in a very small scope, as only in relation to selected parameters and in a very limited its dimension. The situation can change radically. If it will be take into account, the emissions in the production of electricity is necessary for the movement of this type of vehicles Second problem is the energy use amount. We know today that the energy consumption of electric cars, especially in long-term operation is too big. This general knowledge is not confirmed by research results. Both relevant databases and methods of their analysis are missing. This is an unfavourable situation because it is not possible to verify the effects of various changes introduced e.g. in the construction or technology of cars. This publication can be included in those in which it is shown how to change this situation.

The analysis of the results of long-term car use can be used as a verification of various development works, especially in e-mobility, which is only just starting. In the future, it will be need to create the appropriate “big data” databases and a number of tools to analyse the data collected there.

Abstract

The article presents a mathematical model of a permanent magnet motor, powered by a three-phase source of sinusoidal voltage, and a control method. Cooperation between numerical integration algorithms in the differential equation system of the motor and an inverter has been verified. The results of numerical simulations are presented in a graphic form. This article is an extension of the publication [12], in which a model of a drive system was proposed, consisting of: a battery, a supercapacitor and a method of controlling these energy sources during a driving cycle of a vehicle. For vector control, the mathematical model of a synchronous machine in the dq coordinate system is the most common one. The most important feature of this control method is the fact that the iq component of the rotor current vector determines the value of motor torque, and the component id – the value of magnetic flux. In the article, the emphasis is put on how inverters work. Their basic task is to generate such currents iabc or voltages uabc to obtain torque without ripples. It leads to development of different control concepts for achieving this goal, which are related to the modelling of magnetic fluxes in a stator and in an inverter.

Abstract

Hybrid vehicles history begins between XIX and XX century because then has been constructed first hybrid vehicle project. The first men who produced electric propulsion mounted in front hubs connected with generator powered by spark ignition engine was Ferdynand Porsche. Vehicle was called Lohner – Porsche Electromobile. The first en masse produced hybrid vehicle was the first generation Toyota Prius. These model premiere was in 1996, and production started one year later. Vehicle was equipped in 1,5 dcm 58 hp spark ignition engine with added electric propulsion generated 40 mechanical hp. There has been mounting 72 hp spark ignition engine and 44 hp electric generator since 2000. Fuel consumption of these model was 5 liter on 100 km. Beginning XXI century 95% hybrid vehicles were Toyota Prius. The biggest competitor of Toyota Prius was Honda Insight. Lexus and Mercedes started producing hybrid vehicles few years later. The most popular brands selling hybrid vehicles are Toyota and Lexus – Toyota Motor Corporation.

Article describes high voltage battery example diagnostic possibilities in a hybrid or electric vehicle. Constructing vehicle models using two propulsion systems (spark ignition engine and electric generator) cause development and increase control system devices. The measurements has been made by using various diagnostic devices for example: diagnostic scanner mega macs 66, high voltage battery tester. Reading faults code is not enough so it is necessary to use data list what describes this article.

Abstract

In the article, changes in the properties of oils during operation were characterized. The main reason for this is the continuous aging process of the used oil caused by the interaction of oxygen contained in the air, which reacts relatively easily with hydrocarbons and the oxidation process is accelerated just by high temperature. Then the problem of microorganisms occurring in petroleum products and their effect on the properties of oils and the operation of the internal combustion engine was presented. The next part of the article presents effective microorganisms, i.e. what they are and how they work, in particular, their composition and appropriate development conditions. In addition, some of their specific applications were briefly described. In the next part of the article, the research methodology, applied oil samples with additives of effective microorganisms, both for fresh oil and used oil were described. In addition, the measuring test stand with instrumentation and measuring device was shown. The main part of the article contains the characteristics of dynamic viscosity as a function of temperature for fresh oil and used oil compared with oils with the addition of microorganisms in liquid form and ceramic tubes. The developed graphs enabled analysis of the effect of the addition of microorganisms on oil viscosity as ecological products.

Abstract

In the last two decades, there has been observed a noticeable increase in the popularity and availability of air transport services, including regional ones. This intensive development of transport is accompanied by an increase in the adverse impact to the environment, increases noise level, and exhausts emissions, despite the modification and modernization of engines. Determining the emission for regional flights takes into account the specificity of the aircrafts design, such as the size of the aircraft and the performance of the engines. In this article, an attempt was made to determine the CO2 emissions of a business jet flying from Gdansk to Rzeszow. The methodology of the research (the method of calculating emissions based on fuel consumption) and the performance characteristics of the aircraft engines have been described. In the first part of the article, the speed-altitude characteristics of the DGEN-380 engine for different cruise parameters were determined using the virtual engine test bench WESTT CS/B. These characteristics have enabled the engine to match the flight characteristics (altitude, speed). For specific flight parameters, the thrust and fuel consumption were determined. On this basis, for the adopted trajectory and flight time of an aircraft equipped with two DGEN-380 engines, total fuel consumption and CO2 emission factors and values in CRUISE phase was determined with regard to the wind speed and direction. The obtained results were illustrated graphically and discussed.

Abstract

The subject of the article concerns the issues associated with thermal degradation of aviation fuels under high temperature conditions. Due to the intensive development towards increasingly higher thermal loads for both, turbine aviation engines, as well as the used fuels, the issue of thermal stability of the fuel itself is extremely important. In aviation, the fuel, apart from direct participation in energy generation during the combustion process of a fuel-air mixture, also takes part in the heat transfer in many aircraft systems. As a result, requirements in terms of the fuel’s thermal potential are increasingly higher. The standard method for determining the thermal stability of fuel executed on a JFTOT device proves to be insufficient in the context of the appearing issues in current operation. The article presents a non-standard approach to the assessment of aviation fuel thermal degradation with the use of a specialist test rig. The authors believe that the presented methodology and the measurement capabilities of the test rig are valuable supplementary material for the standardized thermal stability test. It allows more thoroughly understanding the phenomena undergoing in the fuel impacted by high temperatures. The article has been prepared within the research project no. 2011/01/D/ST8/06567 funded by the National Science Centre in Poland.

Abstract

There are currently many studies undergoing in the field of using alternative fuels for supplying different types of propulsion units. The ASTM standard in the aerospace industry, allows using five different technologies of manufacturing synthetic components apart from standard oil-based fuel for the propulsion of turbine engines (as a blend up to 50% with conventional fuel). One of these is a technology associated with the process of converting alcohols (isobutanol) to jet fuel – Alcohol to Jet (ATJ). In the research performance, emission parameters were measured on laboratory test rig with miniature turbojet engine (MiniJETRig). The test rig has been created in Air Force Institute of Technology for research and development works aimed at alternative fuels for aviation. The miniature engine was fuelled with conventional jet fuel – Jet A-1 and blend of Jet A-1 with 2-ethylhexanol. The results for this blend were compared with the results obtained for neat Jet A-1 fuel in terms of different engine operating modes, according to specified methodology. The conducted tests did not show significant differences in engine operating parameters (thrust, fuel consumption and thrust specific fuel consumption) and the values of CO, CO2 and NOx emission indices between the tested fuels. The engine tests took place in similar ambient conditions. Laboratory tests of selected physicochemical properties were also carried out for both fuel samples.

Abstract

The article is a review of European aviation regulations with respect to their impact on the design of a new electronic ignition system for aircraft engines. The analysis covers the EASA decision on certification specifications as well as recommended means of compliance and related standards on testing and designing electronic subassemblies and their programming. The analysis focuses on the following aspects: design requirements (system configuration), functional requirements (principles of operation), safety (fault tolerance), material requirements (with regard to corrosion and fire resistance of electronic components) and scope of tests for particular component.

The analysis is illustrated by a case of a research and development project to design and implement an ignition system for a piston engine. The engine with its new ignition system was to be offered commercially as a product of a Polish aircraft engine manufacturer.

The article is a review of European aviation regulations with respect to their impact on the design of a new electronic ignition system for aircraft engines. The analysis covers the EASA decision on certification specifications and their programming. It is illustrated by a case of a particular engine re-engineering project