When and why humanity faced the Energy Problem, it is a question. What was the problem? How are we trying to handle it since the beginning? Do we have enough resources of renewable energy? Which technologies are mature enough to contribute and take part in the solution? Are they available in the market with compatible prices? What is the role of storage for dealing with the intermittent nature of renewable energy resources? Why do we need to build, operate, integrate and manage energy efficiency, storage and renewable energy in harmony with nature by smart grids in sustainable cities of the future? Is transition to 100% Renewable Energy the solution? If so what else is required to reach this target? What are we going to do with the existing system? Which methodologies and techniques we need to use to realize this transition with minimum costs and externalities? How are we going to justify this transition? Is it only a technology problem? What parameters we need to consider when we are trying to live in harmony with nature? How are we going to readapt human beings to be satisfied with minimum ecological footprint societies? Can human beings build democratic societies where energy efficiency and 100% renewable energy is respected and beneficial for each individual of the communities? Transition to 100% renewables requires planning the future with the information of the future. For reaching this target we need to carry on a multidisciplinary approach to understand and take into consideration the basic constraints and requirements of the living space we are sharing all together in the atmosphere. How to Speed-up the Global Transition to 100% Renewable Energy?
Łukasz Muślewski, Michał Sójka, Bogdan Landowski and Marietta Markiewicz-Patalon
The study deals with the results of operational tests of gear oils used in a regional railway transport system. The character of the aging process and the impact of gear oil operation on the main factors determining further usability of gear oil have been defined on the basis of the results of carried out tests. It was proved that transport systems lack reliable convenient diagnostic methods for gear oil used during the process of operation. One of the criteria taken into consideration in decision-making is the period of oil change imposed by the gear manufacturer. The long process of oil application is accompanied by physicochemical changes, which cause degradation of its properties. This phenomenon is referred to as oil aging. This fact can cause loss of viscosity, increase in the amount of pollution, and in effect a decrease in the ability to provide a durable boundary film. The lubricating ability of oil decreases as well. An increase in the amount of pollution is caused by interaction of the collaborating friction elements and by pollutants coming from the gear environment. These changes are of permanent character and reflect the state of new characteristics referred to as operational characteristics. Gear oils have a certain lubricating ability, which is a critical parameter. This study is an attempt to find a way of the oil service life extension and convince the propulsion systems manufacturers that reduction of costs connected with rail vehicle maintenance does make sense.
Bogdan Landowski, Michał Sójka and Łukasz Muślewski
The study deals with the issue of durability extension of multi-phase gears working under temporary or constant loading. The tests were performed for transmission oils used in power transmission systems of beet washers of DC type used in sugar plants. The lubricity parameters of oils and the possibilities of their modification through introduction of low-friction additives to the oil were studied. Additionally, the noise level emitted by working gears was measured before and after addition of the modifier. Lubricity tests were performed on semi-Timken apparatus, on which friction pairs friction roller- roller were tested with the use of oils extracted from the gear. SoundMeter application with MIC002 microphone adaptor was used for measurement of the noise level emission. Tests results have confirmed efficiency of the modifiers as higher values of friction loading were obtained and the noise emission level was reduced. It has been proven that in real operation systems, there is a possibility to increase the value of transmission oil lubricity parameters, which has a direct impact on durability of friction pairs of a gear during its operation.
The article describes processing method of a signal, coming from torsional deflections of an internal combustion piston engine’s crankshaft, registered using two optical encoders ETNP-10. Standard measurement and recording set ETNP-10 enables recording of Instantaneous Angular Speed values encompassing 10 revolutions of the crankshaft, what is equal to 5 cycles of four-stroke engine. That time duration is sufficient for analysis of changes of angular speed caused by, for example, malfunction of fuel injection valve, but is insufficient in case of observation characterized by low frequency changes with period of fluctuations, lower than 0.8 sec. Short time for recording makes impossible following of instantaneous angular speed deviations caused by magnitude modulation of engine’s load value. In the article is presented an algorithm written in MATLAB environment, which allows processing of the data recorded using the recorder DAS 1600 Sefram. The recorded this way signals have around 26 seconds' duration of engine work. Data acquired from two encoders mounted at opposite sides of the shaft, in form of square magnitude signals are transformed into instantaneous speed and subsequently to instantaneous angular shift, what is basis for torsions calculation. In the article is also presented method of elimination of systematic error due to assumed method of averaging. Finally, some examples of results of torsional deflection measurement and analysis are presented.
The article presents the possibilities and validity of the implementation in the field of developing mathematical models for aerobatics trajectory. Proposing a catalogue of three-dimensional figures and those described mathematically will allow improving judging and scoring level, as well as the art of piloting in aerobatics. In the first chapter, article describes the processes of aerobatic flight, judge evaluation method and the current state of technology supporting the scoring process. The second chapter presents the capabilities of the Python programming language, which will be a tool for the construction of three-dimensional models. The third chapter of this article is a description of the comparative analysis of ideal trajectories and obtained in real flight. This chapter also demonstrates the validity and necessity of introducing new standards for assessing aerobatic flights. Aerobatics flights and judging, intelligent system to control aerobatic flights, three-dimensional models of aerobatic flights are presented in the article. The article concerns on use modern technologies to support the judges during the competition. The introduction of ASSD + PL system and the possibility of implementing designed models of aerobatic figures open new paths for improving the art of pilotage and arbitration.
Homogeneous Charge Compression Ignition (HCCI) is a promising low temperature combustion technology which offers high fuel efficiency and extremely low exhaust emissions. However, there are still some pending issues to be resolved before the technology will achieve mass production level. Namely, combustion controllability should be improved and HCCI operating range should be widen. The latter is constrained by excessive combustion rates under high loads. In this study, advanced variable valve actuation strategies were applied to control auto-ignition timings and combustion rates. The examinations were conducted using single-cylinder research engine fuelled with directly injected gasoline. The HCCI combustion was achieved using negative valve overlap technique. The engine was run under boosted conditions, in an operation regime where acceptable pressure rise rate (PRR) level is usually exceeded. Selected valve timing sweeps were carried out within a scope of the experiments to evaluate PRR reduction potential. The obtained results manifested superior combustion controllability. Late exhaust valve closing enabled reduction of the amount of internally re-circulated exhaust, which propagated to the main event combustion. From the intake side, two effects were observed, i.e. variability of the intake air aspiration and variability of the apparent compression ratio. Both phenomena were found to affect combustion timings and rates.
The emulsion is a mixture of two or more insoluble liquids. Microemulsion is the emulsion with particles dimension in a range of one micrometre and smaller. Such a microemulsion of water and diesel fuel will create a novel quality and allows one to simultaneously achieve environmental and economic effects, as well as eliminate the ad-verse impact of normal emulsions, or adverse effects of water injection into the engine intake system or directly into the combustion chamber, as well as the sequential injection of water directly into the combustion chamber. Application of microemulsion of water and diesel to fuel diesel engine positively affects the combustion process through the catalytic impact of microparticles of water, and improves the process of preparation of the microemulsion injection into the combustion chamber as a result of water microparticles’ microexplosions. This article presents the investigation results of an internal combustion engine fuelled by an emulsion of water and diesel fuel and fuelled by emulsion of FAME and water. It therefore seems appropriate to a strong increase in the degree of dispersion of water droplets in the emulsion by applying the methods to obtain the size of water droplets on nanometric range. This should dramatically improve both the stability of emulsion and its influence on the chemical effects of combustion in diesel engine.
Tomasz Białecki, Wojciech Dzięgielewski, Bartosz Gawron, Urszula Kaźmierczak and Andrzej Kulczycki
This article presents the results of investigations focused on the role of molecularly ordered structures (molecular clusters) on combustion process. The proposed new mechanism of the reactions initiation takes into account the role of molecular clusters in energy (heat and energy of electrons emitted by the surface of the walls of combustion chamber) conductivity regulation. Literature survey shows that molecular clusters created by aromatic hydrocarbons are responsible for particulate matter. The combustion process itself is not uniform in whole combustion chamber. Such diversity, caused mainly by heterogeneous thermal state of combustion chamber is recognized as significant reason to create various products of combustion including carbon oxides, carbon dioxides and nitrogen oxides. Jet fuel and its blends with n-butanol and biobutanol in concentration from 10 to 75 % (V/V) were subjected to laboratory tests. Such blends were also tested on the test rig with a miniature turbojet engine – MiniJETRig. Engine operating parameters and carbon oxide emission were measured. The relations between electrical conductivity and parameters of engine test (e.g. temperature in selected points in combustion chamber) were assessed. Engine tests were carried out according to specific profile of engine test, which models different engine operating modes. The results of experimental investigations, shown in the article, initially confirm the proposed mechanism of the oxidation reactions initiation during combustion process.
The article presents classification of automatic identification and data acquisition techniques (AIDC) as well as techniques for indoor positioning of objects supporting logistic processes, including especially warehousing processes. The use of presented solutions and the possibility of combining AIDC technics with indoor positioning systems to increase the efficiency of logistics processes in warehouses were discussed. This combination can make a tool supporting rational decision making for allocation of idling employees and vehicles to warehouse tasks and reducing empty runs on the base of position analyse. Then, the idea of using popular AIDC devices − mobile terminals with and without RFID scanners to track the position of employees was presented and discussed. Mobile terminals can provide information about position, which can be used for the allocation of tasks (the reverse functions of mobile terminals). Review of AIDC techniques in warehouses and industrial facilities, information flow in AIDC techniques, positioning techniques in a closed space, Resources positioning and the efficiency of the warehouse process, typical and new approaches to positioning resources in warehouse, the reverse function of mobile terminals are presented in the article.
A diagnostic FDM-A method, based on the measurement of modulation of constituent frequency of direct current (DC) generator pulsation as well as FAM-C method, established on the measurement of frequency modulation of alternating current (AC) generator, were developed in the Air Force Institute of Technology [3, 9-10]. The essence of their accuracy lies in “natural” synchronizing of sampling with angular speed of the observed kinematic pair – if the dynamic processes of the observed object accelerate, the sampling becomes faster too [9-10]. At the same time, around the “synchronization points”, due to the clearance in the power transmission there is a certain natural oscillation between the observed kinematic pair and generator’s rotor − vibrations are created. These vibrations are called jitter [9, 23] and they constitute an additional supplement to this method, because they provide more information on resolution and accuracy. Moreover, the abovementioned method enables to define the level of subassembly abrasive wear and its location in the time of normal operation of the powerplant [9-10]. This method allows also detecting resonances of elements on the basis of observation of shape and relative position of characteristic sets, which i.e. enable to calculate the mechanical quality factor of kinematic pair − it is possible to establish the operation time of kinematic pair until entering the resonance degradation. Other numerous parameters associated with the assembly of power unit rotor were also outlined: rotor skew angle, level of frictional wear of bearing cage − lack of contact of bearing components, bearing assembly ovalisation.