Wyniki wyszukiwania - BazTech

1

Research and Solution Proposals to Optimize Distribution Power Grids in Smart Grid Condition

Pham Trung Son, Nguyen Dinh Tien, Nguyen Quang Thuan, Dang Quang Khoa

Inżynieria Mineralna

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2021

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no. 2

479--486

EN

Smart Grid is a concept for transforming the electric power grid by using advanced automatic control and communications techniques and other forms of information technology. It integrates innovative tools and technologies from: generation, transmission and distribution. This also includes consumer appliances and equipment. This concept integrates energy infrastructure, processes, devices, information and markets into a coordinated and collaborative process. All allowing energy to be generated, distributed and consumed flexibly and efficiently. However, the Smart Grid with the integration of distributed generation itself also creates a several disadvantages. There can be problems with: stability and reliability, relay protection, isolation and operational isolation in which the problem is to create a burden on the distribution grid when transmitting electrical energy sources. Optimizing power flow and bringing high operating efficiency on Smart Grid conditions is an urgent issue. This paper focuses on researching and proposing solutions for optimal calculation of power flow on Smart Grid. The paper has researched, and analyzed calculation solutions to optimize power flow and proposed to use the Lagrange multiplier method. The study performed calculations for a typical Smart Grid model with three distributed generations. Calculation results have shown that the role of the method is to fully perform the optimal calculation of the power flow on the grid. This is in order to reduce power loss and energy loss as well as increasing operational efficiency while improving power quality in Smart Grid conditions.

2

Prechamber optimal selection for a two stage turbulent jet ignition type combustion system in CNG-fuelled engine

Pielecha Ireneusz, Bueschke Wojciech, Skowron Maciej, Fiedkiewicz Łukasz, Szwajca Filip

Combustion Engines

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2019

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R. 58, nr 1

16--26

EN

Searching for further reduction of fuel consumption simultaneously with the reduction of toxic compounds emission new systems for lean-mixture combustion for SI engines are being discussed by many manufacturers. Within the European GasOn-Project (Gas Only Internal Combustion Engines) the two-stage combustion and Turbulent Jet Ignition concept for CNG-fuelled high speed engine has been proposed and thoroughly investigated where the reduction of gas consumption and increasing of engine efficiency together with the reduction of emission, especially CO2 was expected. In the investigated cases the lean-burn combustion process was conducted with selection of the most effective pre-combustion chamber. The experimental investigations have been performed on single-cylinder AVL5804 research engine, which has been modified to SI and CNG fuelling. For the analysis of the thermodynamic, operational and emission indexes very advanced equipment has been applied. Based on the measuring results achieved for different pre-chamber configurations the extended methodology of polioptimization by pre-chamber selection and the shape of main chamber in the piston crown for proposed combustion system has been described and discussed. The results of the three versions of the optimization methods have been comparatively summarized in conclusions.

3

Optymalizacja układów przeróbki kruszyw z obiegiem zamkniętym nadziarna

Malewski J.

Kruszywa : produkcja - transport - zastosowanie

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2017

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Nr 3

52--56

PL

Systemy przeróbki kruszyw to 3-4-stadialne układy rozdrabiania i klasyfikacji o zróżnicowanych funkcjach jakościowo-ilościowych. Ostatnie stadia odpowiedzialne są za jakość produktów finalnych. Projektuje się je jako układy z obiegiem zamkniętym nadziarna. Efektywność takich systemów w procesach projektowania lub eksploatacji jest przedmiotem tego artykułu. Na przykładach obliczeniowych pokazano różnice pomiędzy układem 3- i 4-stadialnym oraz omówiono problem optymalizacji ich parametrów wg kryteriów ekonomicznych lub ilościowych. Pokazano również sens ekonomiczny i możliwości zwiększenia efektywności produkcji przez optymalizację parametrów kruszarek w takich układach.

EN

Aggregates technologies consist of 3 to 4 crushing and classification subsystems of different qualitative and quantitative functions. The last processing stages are responsible for the quality of final products. They are designed, as a rule, as closed circuit oversize subsystems. The effectiveness of such systems in the design or operation phase is the subject of the paper. Exemplary calculations show that differences between 3- or 4-stage systems are not clear. However their economic sense and the possibility to increase the production efficiency by optimizing crushers settings in such systems have been presented.

4

Multi-criteria fuel system optimization with an electronic control unit

Wróblewski A.

Combustion Engines

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2017

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R. 56, nr 1

51--55

EN

This paper presents the results of the multi-criteria synthesis of a diesel engine fuel system using the optimization method. The optimization criteria, functional restrictions and quality criteria have been selected. The efficiency of the proposed method was demonstrated using the example of a diesel engine with the Common Rail system.

5

Optimization of innovative project realization conditions

Kvilinskyi O., Kravchenko S.

Zeszyty Naukowe Politechniki Poznańskiej. Organizacja i Zarządzanie

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2016

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Nr 70

101--111

EN

A characteristic feature of the innovation process is the uncertainty with the term of efficient use of the new product. The article proposes the use of the "modified internal rate of return" indicator for determining the period of implementation of aninnovative project. The application of the present recommendations contributes to anincreased objectivity while making important managerial decisions related to setting an optimal duration of innovation use, planning the efficiency value of the employed capital, comparing alternative innovative projects, and also predicting the need for further development of innovations or their complete replacement by more progressive ones.

PL

Charakterystyczną właściwością procesu innowacyjnego jest nieokreśloność dotycząca terminu efektywnego wykorzystania wprowadzanych know-how. W artykule dla określenia terminu realizacji projektu innowacyjnego zaproponowano wykorzystanie charakter zależności wskaźnika „modyfikowana wewnętrzna norma dochodowości” od zmiany długotrwałości wskazanego okresu. Wykorzystanie zaproponowanych rekomendacji pozwala zaprowadzić optymalną długotrwałość wykorzystania innowacji, zapewnić możliwość planowania efektywności wykorzystania kapitału, a także prognozowania momentu powstania potrzeby w modernizacji innowacji albo pełnej ich zamianie innymi, bardziej progresywnymi.

6

Aerodynamic optimization of drone propulsions fairing cover

Wąsik M., Skarka W.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

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2016

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z. 3/107

99--106

EN

In the article is presented the study of the influence of the drones fairing cover on its aerodynamic characteristic. The research is an answer for some needs in the autonomous exploratory flying robots’ area. The study is basing on the authors developed method for conducting aerodynamic research for such objects. Altair HyperWorks software was used for the numerical analysis. The CAD models were prepared with CATIA V5 software. The main idea of the research was the numerical calculation of the aerodynamic drag force and its coefficient- cx and study of the influence of the drones fairing cover on its aerodynamics. The expected result it is the optimal set of parameters of the fairing that give the best aerodynamic characteristic of the drone and optimization methodology for such objects.

PL

W ramach artykułu przeprowadzono studium wpływu dodatkowej owiewki napędu drona na jego własności aerodynamiczne. Przeprowadzone badania są odpowiedzią na pewien zaistniały problem w dziedzinie eksploatacyjnych robotów latających. Do przeprowadzenia analiz aerodynamicznych oraz optymalizacji zastosowano oprogramowanie Altair HyperWorks. Modele CAD utworzono w oprogramowaniu CATIA V5. Głównym celem przeprowadzonych badań było wyznaczenie siły i współczynnika cx oporu aerodynamicznego analizowanych owiewek. Uzyskanym rezultatem jest zbiór parametrów owiewki poprawiającej charakterystykę aerodynamiczną drona oraz metodyka optymalizacji tego typu obiektów.

7

Anticollision manoeuvre optimization in the NAVDEC system

Koszelew J., Wołejsza P.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 2

27-30

EN

Authors presented the concept of improved time optimization algorithm of anticollision manoeuvre to be implemented in the NAVDEC system. The algorithm will play an important role in supporting the navigator in decision making process. Moreover implementation of the algorithm will reduce significantly fuel consumption. In conclusion, safety and economic efficiency of shipping will be improved.

PL

Autorzy przedstawili ulepszony algorytm optymalizacji czasu manewru antykolizyjnego, który zostanie zastosowany w systemie NAVDEC. Algorytm odegra istotną rolę w procesie wspomagania decyzji nawigatora. Ponadto, implementacja algorytmu zredukuje znacznie zużycie paliwa. Reasumując, poziom bezpieczeństwa oraz efektywność ekonomiczna zostanie poprawiona.

8

The Influence of Short-Term Aging on Properties of the Asphalt Mixture in WMA Technology

Cholewińska M.

Logistyka

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2014

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nr 4

4178--4185, CD6

EN

The paper deals with the influence of short-term aging on the properties of the Stone Mastic Asphalt mixture (SMA) produced in warm-mix asphalt technology (WMA). Fischer-Tropsch wax was used as a bitumen viscosity-reducing modifier. Basic properties of the modified bitumen were tested. The content of the low-viscosity agent in the bitumen was optimised. The results from the tests of the SMA mixture produced in the WMA technology with the optimum wax were compared with those from the tests of the traditional SMA mixture produced in the HMA technology. The SMA mixture manufactured in the WMA technology was found to have better properties than the traditional SMA mixture.

PL

W artykule zaprezentowano wpływ starzenia krótkoterminowego na właściwości mieszanki mastyksowogrysowej SMA wytworzonej w technologii “na ciepło” (WMA). W roli modyfikatora obniżającego lepkość asfaltu zastosowano wosk syntetyczny Fischera-Tropscha. Wykonano badania podstawowych właściwości modyfikowanego asfaltu. Dokonano optymalizacji środka niskowiskozowego w asfalcie. Przedstawiono wyniki badań mieszanki SMA wykonanej w technologii “na ciepło” z optymalną zawartością wosku syntetycznego oraz tradycyjnej mieszanki SMA w technologii “na gorąco”. Stwierdzono, że mieszanka SMA wytworzona w technologii WMA posiada lepsze właściwości od tradycyjnej mieszanki SMA.

9

Identification of Johnson-Cook Equation Constants using Finite Element Method

Grązka M., Janiszewski J.

Engineering Transactions

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2012

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Vol. 60, iss. 3

215-215

EN

The objective of this work is to develop an identification technique of the Johnson-Cook equation constants for copper Cu-ETP samples. In this paper we describe a method of constant identification using the Taylor impact test and finite element analysis. Nowadays the most popular method of constant identification method is the split Hopkinson pressure bar technique. This method is quite easy but needs very expensive laboratory equipment. To implement this method we have to make a lot of different tests in order to have enough information about dynamic properties. We decided to prepare an identification process algorithm using the Taylor impact test as a basic type of experimental and numerical simulation

10

Meteorologiczny rok odniesienia do obliczeń energetycznych (WYEC2) dla potrzeb optymalizacji fasad budynków

Narowski P, Janicki M, Heim D

Fizyka Budowli w Teorii i Praktyce

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2011

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T. 6, nr 2

67--76

PL

W pracy omówiono podstawowe formaty zestawów danych meteorologicznych tworzonych dla potrzeb symulacji energetycznych budynków. Podjęto próbę opracowania Meteorologicznego Roku Odniesienia (WYEC2) dla pięciu wybranych lokalizacji w Polsce. W opracowaniu wykorzystano 30-letnie, rzeczywiste dane pomiarowe ze stacji meteorologicznych. Do obliczeń wielkości pośrednich wykorzystano zaawansowane modele transferu promieniowania z uwzględnieniem procesów fizycznych zachodzących w atmosferze. Podczas generowania lat obliczeniowych przyjęto odmienne od typowych wagi indeksów poszczególnych parametrów. Przy doborze wartości indeksów brano pod uwagę specyfikę analizowanego problemu obliczeniowego - dystrybucję masy i energii w przestrzeniach fasad podwójnych. Za najistotniejsze parametry przyjęto: temperaturę, promieniowanie słoneczne oraz kierunek i prędkość wiatru. Wpływ przyjętych kryteriów oraz lokalizacji budynku na końcowy wynik obliczeń zilustrowano przykładem zamieszczonym na końcu opracowania.

EN

The discussion about basic format of meteorological data sets is presented in the paper. Initially, reference year WYEC2 - „Weather Year for Energy Calculations, Version 2” was created especially for the purposes of building energy simulation on ASHRAE demands. In presented case study WYEC2 data were developed for five selected locations in Poland. 30-year actual measurements from meteorological stations have been taken into consideration. To accurately account all physical phenomena and dynamics of the processes simulation methods needs to apply precise and specified at least hourly meteorological data, including inter alia: temperature, relative humidity, wind speed and direction, solar direct and diffuse radiation distribution. Due to lack of hourly measurements, 3-hours complete observations records have been selected and transformed via originally developed programs TMY.EXE and MIP.EXE into typical meteorological year files. Mentioned programs have implied engine, which allows to select appropriate algorithms and weight factors to interpolate 3-hours time-step data into hourly ones. As the most important transform parameters were considered: dry bulb temperature, total solar irradiance and wind speed. On the basis of the calculations five files for five representative locations were computed (for Szczecin, Białystok, Lodz, Wroclaw and Rzeszów). Implemented in the tool, described wider in work [7], data allowed to conduct computational energy simulation. On the figures 22 and 23 have been illustrated outputs of the simulations. It can be stated, that the method of adopting meteorological parameters, such as weigh factor assigned to dry bulb temperature, total solar radiation and wind speed have a direct impact on the processes occurring in the facade and the obtained results.

11

Thermodynamic optimization of irreversible heat pumps

Sarkar J., Bhattacharyya S., Ramgopal M.

Archives of Thermodynamics

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2008

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Vol. 29, no. 3

59-68

EN

The performance of an irreversible heat pump for simultaneous cooling and heating applications, for which irreversibilities results from both the finite size and finite rate of heat conduction, as well as compression and expansion, is studied. The relation between optimum system coefficient of performance and optimal rate of combined cooling and heating output has been established. Also relations for optimal cold and hot fluid temperatures have been derived and performance of irreversible heat pump has been discussed. The optimal correlations have been simplified for endoreversible cycle and compared with the relation for only cooling or hearting in the literature. Consequently, optimal relations for heat conductance inventory, residence time and mass distribution between the heat exchangers have been established.

12

Study and improvement of a trapezium-metacarpal prosthesis in relationship with the bone remodeling phenomena

Lamblin D., Guerlement G., Van Parys L., Datoussaid S.

Computer Assisted Mechanics and Engineering Sciences

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2006

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Vol. 13, No. 4

583-592

EN

Simulation of the long term behavior of a metacarpal bonę with a prosthesis is presented with the help of an evolutive 3D finite element model taking into account "the stress słiielding" phenomena. The same model allows to improve the shape of the prosthesis.

13

Optimization procedure of blade cooling system

Nowak G., Nowak I., Chmielniak T.

Archives of Thermodynamics

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2006

|

Vol. 27, no. 3

63-82

EN

This paper discuses the problem of cooling system optimization within a gas turbine vane. The analysis involves the optimization of the location and size of internal cooling passages (circular and noncircular) within the vane. Shape of a noncircular passage is modelled with Bezier's splines. The analysis is performed by means of the genetic algorithm for the optimization task and FEM for heat transfer predictions within the component. In the present study the vane profile is assumed as aerodynamically optimal.

14

Modelling and optimisation of cogeneration plant thermal cycle

Panowski M., Klajny R.

Archives of Thermodynamics

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2006

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Vol. 27, no. 4

179-188

EN

The optimal control of the process of energy production is the cheapest way of increasing its thermal efficiency. However, the possible benefits could be achieved both by setting optimal values of thermodynamic parameters as well as by decreasing the time span of change of these values, dependent upon change of cogeneration plant energy load. Computer-aided modelling and optimisation applied to these two aspects of steering can be done with use of accessible computer software and should lead to economical profits through the thermal cycle efficiency increase. A new methodology of optimal thermal cycle steering is presented in this paper. This methodology is based on local data models formulated owing to data obtained from the simulation software. Optimisation procedures are applied to found the best values of thermodynamic parameters of the thermal cycle which realise one of the important steering aspects. Moreover, because of using simulation software the calculations are fast enough to realise also the second one. This paper also presents application of methodology and evaluated numerical procedures to optimisation of thermal cycle of cogeneration power plant for which the simulation model was also elaborated. Optimisation process was made for different thermodynamic parameters with respect to total egzergetic and energetic efficiency of the cycle.

15

Optimizacia plotnosti setki skvazin s cel'u uvelicenia nefteotdaci

Muzicko I. I., Gusul V. V., Pita I. V., Mirzoan L. E.

Prace Instytutu Górnictwa Naftowego i Gazownictwa

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2002

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nr 116 wyd. konferencyjne

489--494

16

In defence of mean variance optimisation

Adock C. J.

Management

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2001

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Vol. 5, no 1

107-118

EN

The construction of optimised portfolios of risky financial assets is usually carried out using quadratic programming. The use of this optimisation method is justified by the assumption that returns follow a multivariate normal distribution and/or the investor espouses a quadratic utility function. Such utility functions are criticised on the grounds that, according to the quadratic model, there are situations in which the investor will prefer less wealth to more wealth and that risky assets are regarded as an inferior good. In this paper, it is shown that, for normally distributed retums, this criticism of the quadratic utility function is unjustified. A number of relevant results are summarised and some extensions are given. These show that any utility function willlead to a point on the Markowitz mean-variance efficient frontier. The same property also holds in the presence of transactions costs. The paper discusses the implication of these results and concludes with a brief summary of the problems that arise when return s are not normal.