Wyniki wyszukiwania - BazTech

1

Crucial problems of powertrain control in electric vehicles and hybrid electric vehicles

Chang Yuhua

Prace Naukowe Politechniki Warszawskiej. Mechanika

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2019

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z. 271

3--76

EN

This work deals with how to improve the energy efficiency, the safety, reliability and the driving comfort by powertrain control in EVs and HEVs from three aspects: 1) How to improve the energy efficiency: Using two cases study in Chapter 2 to present the idea about how to improve the powertrain efficiency of EVs and HEVs. On the other hand, the simulation study shows the current solution in EVs of increasing the driving range by enlarging battery pack size is at the expense of EVs energy efficiency, not to mention the increasing cost and the increasing difficulty of battery management system (BMS); 2) How to improve the safety and reliability by BMS: Battery is the most expensive component both in pure electric and hybrid powertrain. People expect the battery as a green energy solution to liberate society from the dependency of fossil fuel. The reality is that battery has many limitations and battery performance strongly depends on how the batteries are used and also on the environmental conditions. BMS should be designed to keep the battery within a safe operating window and to ensure a long cycle life based on battery limitations and performance characteristics. The popular used Thevenin battery model is analyzed to be linear and to be an improper model for state of charge (SOC) estimation. The nonlinear dynamic battery model (developed by Prof. Szumanwoski in 1980's) is used to develop the Li-ion battery model in numerical way. Finally an improved algorithm for battery SOC estimation is proposed in Chapter 3. 3) How to improve the driving comfort and reliability: a design methodology based on the co-design of scheduling and control is proposed in Chapter 4. Both the simulation and HIL test results show the method can effectively deal with the problem resulted from network-induced delays and network congestion, and can ensure the reliable and dependable control system for electric powertrain system in EVs and HEVs. This work also shows that the powertrain design and its control for EVs and HEVs are highly multidisciplinary, which requires researchers and engineers to have multidisciplinary knowledge or to cooperate closely. When people from different disciplines try to understand basic problems from other disciplines and work together closely, they may easily find the reasons and solutions to the problems. Nowadays EVs and HEVs are just at the beginning of mass production. Some unreliable driving phenomena have reported to appear during EVs operating, engineers haven't found the reason yet. As the number of EVs and HEVs entering into the market increases, more and more technology challenges will appear. For researchers it is also very important to work together with vehicle engineers to find the real reason of unreliable driving phenomena, and to use the research results to resolve the problems. Currently the auto industry is undergoing a radical transformation to phase out conventional vehicles (CVs) powered solely by internal combustion engines (ICEs.) Opportunities and challenges exist both for the auto industry and for auto research institutions. The Author believes that the trend for future vehicle powertrain will be all-electric and hybrid, and the current powertrain technology for EVs and HEVs has many aspects and potential to improve. In next decades, the development of powertrain for EVs and HEVs will focus on how to increase the energy efficiency, improve the safety, reliability and driving comfort, at the same time to make the powertrain more compact.

2

5S system as a manner for improving working conditions and safety of work in a production company

Kabiesz Patrycja, Bartnicka Joanna

Multidisciplinary Aspects of Production Engineering

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2019

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Vol. 2, Iss. 1

496--507

EN

Currently entrepreneurs have the opportunity to use many methods and tools that support production management, quality and improvement of working safety. A method worth paying attention to is the 5S method, which brings order and discipline to the workplace. The article presents practical aspects of the implementation of the 5S method using five simple steps that give the real benefits to a company. Particularly the specific solutions that can be applied at every stage of the implementation of the 5S method is indicated. Also innovative ways of conducting internal audits are presented. In addition, a model for the implementation of the 5S concept was proposed, which supports maintaining the healthy standards at a high level. It has been pointed out that the implementation of 5S rules must be constantly monitored and improved. Therefore, supervision and motivational activities are particularly important, especially from the side of leaders and managers represented an organization.

3

Layout design for efficiency improvement and cost reduction

Kovács G.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 3

547--555

EN

In a reality of global competition, companies have to minimize production costs and increase productivity in order to boost com-petitiveness. Facility layout design is one of the most important and frequently used efficiency improvement methods for reducing operational costs in a significant manner. Facility layout design deals with optimum location of facilities (workstation, machine, etc.) on the shop floor and optimum material flow between these objects. In this article, the objectives and procedure of layout design along with the calculation method for layout optimization are all introduced. The study is practice-oriented because the described case study shows how the layout of an assembly plant can be modified to form an ideal re-layout. The research is novel and innovative because the facility layout design and 4 lean methods (takt-time design, line balance, cellular design and one-piece flow) are all combined in order to improve efficiency more significantly, reduce costs and improve more key performance indicators. From the case study it can be concluded that the layout redesign and lean methods resulted in significant reduction of the following seven indicators: amount of total workflow, material handling cost, total travel distance of goods, space used for assembly, number of workers, labor cost of workers and the number of Kanban stops.

4

Continuously variable transmission leakage test results

Goszczak Jarosław, Radzymiński Bartosz, Mitukiewicz Grzegorz

Acta Innovations

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2019

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no. 31

5--13

EN

After a short introduction characterizing the general outline of the issue, this paper describes the test results of oil leakage measurements through CVT actuator seals. The research was done using Jatco company's CVT 7model, the popular gearbox for small passenger cars. Several curves of leakage values are given for both actuators, concerning different conditions such as rotational speed, oil temperature or pressure. In the summary several conclusions are formulated, based on presented test results. The determined maximal value of leakage is about 1 l/min. It emerged that the influence of centrifugal force is negligible. What is more, the observed phenomena are shortly described and projected for more detailed investigation.

5

Audyty energetyczne przedsiębiorstw zajmujących powierzchnie biurowe

Dybiński O., Kwiatkowski J.

Materiały Budowlane

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2018

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nr 1

28--30

PL

W artykule opisano podstawy prawne przeprowadzania audytów energetycznych przedsiębiorstw w Polsce oraz metodę wykonywania audytów. Na podstawie doświadczeń uzyskanych po wykonaniu wielu audytów, opisano zalecaną metodę i typowe problemy występujące przy audytach przedsiębiorstw zajmujących powierzchnie biurowe. Dzięki uzyskanym wynikom opracowano statystykę zużycia energii w tego rodzaju przedsiębiorstwach oraz opisano możliwości poprawy ich efektywności energetycznej.

EN

Legal bases of performing of energy audits of enterprises and applied methodology in Poland has been described. Based on experience gained through performing many energy audits, recommended methodology and typical problems occurring during energy audits of companies located in office buildings has been presented. Thanks to results obtained, statistics of typical energy consumption have been developed and recommended energy efficiency improvements have been shown.

6

Performance assessment and leakage analysis of feed water pre-heaters in natural gas-fired steam power plants

Shabani G. A. S., Ameri M., Akbari O., Seifi A.

Journal of Power Technologies

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2018

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Vol. 98, nr 4

352--364

EN

The performance of feed water pre-heaters (FWH) at a steam power plant with a capacity of 200 MW is evaluated in this paper. The main objective of this study is to investigate the behavior of these FWHs in various cases. The effect of leakage of condensates on the condenser was also studied in detail. To do this, each FWH was studied separately and also in groups (LP, HP and both groups). While some of the results are exclusive to the studied power plant, others can be generalized to similar power plants. The results show that although LPH-1 and LPH-2 have the lowest exergy efficiency, they have the greatest effect on the efficiency of the cycle. Whereas HPH-6 and LPH-4 have the highest heat exchange (31.3 and 21.73 MW), LPH-2 and LPH-1 deliver the greatest positive effect on energy efficiency (0.81% and 0.61/0%). Moreover, the results show the particular importance of preventing any leakage of heater condensate. In the event of leakage along the route to the condensate of heaters, the most negative effect will be due to the HP heaters: 20 kg/s leakage in the HPHs line will cause an increase in CO2 production p.a. of roughly 10150 metric tons. Furthermore, energy efficiency and power produced will fall by 0.374% and 5.1 MW. In terms of the impact of leakages on the cooling tower, the study showed that LPH-1 and LPH-2 have the greatest effect. The effects of LP and HP FWHs on the energy efficiency of the cycle were 2.53% and 0.82%.

7

Facility layout redesign for efficiency improvement and cost reduction

Kovacs G., Kot S.

Journal of Applied Mathematics and Computational Mechanics

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2017

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Vol. 16, nr 1

63--74

EN

In a competitive market the manufacturing companies have to produce cost effective products which can be realized by minimized production cost and higher effectiveness. The effective facility planning can significantly reduce the operational costs of companies. An adequate facility layout can result in the improvement of the performance of the production line. The Facility Layout Problem (FLP) is relating to location of objects (departments, workstations, machines, etc.) on a given site and the material flow between these objects. The goal of this study is to show the reasons, objectives and steps of a layout redesign process. The minimization of the workflow realized on the shop floor is an often applied an objective function during the layout redesign. Material flow efficiency is a commonly used term for the determination of the amount of workflow, which is the multiplication of material flow data and distance data. In this study, this mathematical method for workflow calculation is introduced. The described case study shows how the efficiency and reduced manufacturing cost of a real manufacturing system can be improved by re-layout design, while smaller floor space is needed for the production.

8

Celowość badania wieszaków ścian trójwarstwowych docieplanych budynków

Wójtowicz M.

Materiały Budowlane

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2016

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nr 11

6--9

PL

Wymagania dotyczące oszczędności energii na ogrzewanie powodują konieczność dodatkowego docieplenia ścian budynków. W budynkach wielkopłytowych ze ścianami trójwarstwowymi dodatkowe obciążenia dociepleniem przenoszą łączniki ścian. Stan techniczny takich łączników (wieszaków) jest niezadowalający, dlatego też niezbędne jest stosowanie dodatkowych kotew, bez konieczności wykonywania pełnej oceny bezpieczeństwa ścian.

EN

The introduced requirement for energy savings on heating cause the need for additional insulation of walls of buildings. In case of buildings with three layered walls the additional loads by thermal insulation are transfered by the anchors of the walls. The technical condition of the anchors of the walls (the suspension rods) is unsatisfactory. Hence, it is necessary to use additional fixings (anchors), without having to perform a full evaluation of the safety of the walls.

9

Improving the Efficiency of a High Speed Catamaran Through the Replacement of the Propulsion System

Melo G., Echevarrieta I., Serra J. M.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2015

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Vol. 9, no. 4

531--535

EN

The high speed vessels are primarily designed for short distances services as public transport of passengers and vehicles. The range of high speed, according to the Code of high-speed vessels begins at 20 knots, which depends on the cruise speed you desire for your vessel; you will have to use the most appropriate type of propellant. In general, in the past 20 years, they have been building high-speed vessels with speeds above 33 knots, which meant installing water jet propellants coupled to powerful engines and therefore of high consumption of fuel, increasing operating costs and causing increased air pollution. Although the prices of fuel have been reduced to half, due to the sharp fall in oil prices, the consumption of fuel and the air pollution remains high at these speeds and powers used, in addition to that the reduction of the time spent on each trip is not excessive, mainly in short routes that are less than an hour . This article is about adapting a ship of high-speed service, with a maximum speed in tests of 34 knots and to reduce its operating costs (fuel, maintenance, etc.) and make it economically viable; before the transformation, this vessel was operating with a service speed of 22 knots, and with a consumption per mile of 135 litters of MGO. The transformation process has consisted by: – Replacement of the two original water jet with four shaft lines with fix pitch propeller. – Replacement of the two original main engines (2 x 6500 kW = 13000 kW) by four engines (4 x 1380kW = 5.520 kW). – Changing the underwater hull shape to fit the new propellers and maximize its efficiency. – Relocation of auxiliary engines, to achieve the most efficient trim. – Installation of two lateral propellers to improve maneuverability and shorten the total time of journey. After the reform and the return to service of the vessel with a service speed of over 22 knots, it has been verified that the consumption per mile is of 45 litters MGO, representing a reduction of 65% of consumption and even more reduction of emissions as the new engines comply with the latest regulations.

10

Transgraniczny przesył ciepła

Kostrzewski J., Łopusiewicz J., Przyłucka A., Baranowski B., Dąbrowski D., Kieruczenko M., Koczergo K., Olejnik R., Sobkowiak C.

Instal

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2015

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nr 9

26--30

PL

Ciepło systemowe bez granic – to fakt. Należąca do Szczecińskiej Energetyki Cieplnej spółka SEC Słubice i niemieckie Stadtwerke Frankfurt (Oder) połączyły swoje systemy ciepłownicze. Od marca 2015 r. wzajemnie sprzedają sobie ciepło i świadczą usługi przesyłowe. To pionierski projekt w skali Polski. Przesył ciepła odbywa się w sposób rewersyjny (tzn. w obie strony). Współpraca potrwa minimum 15 lat, z możliwością jej przedłużenia. Roczny bilans sprzedaży/wymiany ciepła wyniesie 57 tys. GJ. W połączenie systemów strona niemiecka zainwestowała około 2,8 mln euro, a polska 1,4 mln zł.

EN

System heat without borders – it’s a fact. SEC Słubice, a company owned by Szczecińska Energetyka Cieplna, and German Stadtwerke Frankfurt (Oder) have connected their heating systems. Since March 2015 they have been selling heat and providing transmission services to each other. It is a pioneering project in Poland. The transmission of heat is a reversible process (i.e. it occurs in both directions). The cooperation will be continued for a minimum of 15 years, with the possibility of extending this period. The annual sales/heat exchange balance will reach 57 thousand GJ. The connecting of the systems involved an investment of approx. EUR 2.8 million by the German party and PLN 1.4 million by the Polish party.

11

Poprawa sprawności obiegu parowego bloku energetycznego – teoria i rzeczywistość

Radzik T.

Energetyka

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2014

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nr 7

397--405

PL

Opisano sposoby podnoszenia sprawności obiegu parowego Rankine’a na przykładzie bloków kondensacyjnych o dużych mocach w krajowych elektrowniach zawodowych. Przeanalizowano sposoby i rozwiązania technologiczne wpływające na zwiększenie sprawności głównych urządzeń składających się na blok energetyczny, takich jak kocioł parowy opalany węglem oraz turbozespół parowy. W skrócie omówiono podstawy teoretyczne poprawy sprawności oraz szerzej praktyczne osiągi parowych bloków energetycznych. Przedstawiono obecne możliwości poprawy sprawności obiegu parowego umożliwiające zwiększenie efektywności wytwarzania energii elektrycznej oraz pośrednio obniżenie emisji do środowiska. Aspekty te należy rozważać szczególnie wnikliwie przy podejmowaniu decyzji o ewentualnej modernizacji istniejących bloków energetycznych lub budowie nowych jednostek.

EN

Described are methods to improve the Rankine cycle efficiency on the example of big output condensing units in the Polish commercial power plants. Analysed are methods and technical solutions influencing efficiency improvement of main power unit elements like a coal-fired steam boiler and a steam TG unit. Discussed is briefly a theoretical base for efficiency improvement and, more broadly, a real performance of some steam power units. Presented are existing possibilities of steam cycle efficiency improvement enabling increase of electric power generation efficiency and, indirectly, reduction of environmental pollution. All these aspects should be thorougly considered when making a decision of a possible modernization of the existing power units or building the new ones.

12

Analiza możliwości socjoekonomicznych wzrostu efektywności energetycznej w budownictwie na przykładzie Lublina

Ostańska A.

Przegląd Budowlany

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2011

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R. 82, nr 5

29-36

13

Analiza możliwości i skutków socjoekonomicznych wzrostu efektywności energetycznej w budownictwie na przykładzie Królestwa Niderlandów

Konrad M.

Przegląd Budowlany

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2011

|

R. 82, nr 3

40-43

14

Nadkrytyczne bloki węglowe. Kierunki poprawy sprawności i ograniczenia emisji CO2

Chmielniak T., Łukowicz H., Kochniewicz A., Mroncz M.

Energetyka

|

2011

|

nr 2-3

84-87

PL

Omówiono pozytywny wpływ wprowadzenia odzysku ciepła ze spalin na zmniejszenie zużycia paliwa przy stałej mocy bloku 460 MW. Oprócz oszczędności paliwa obniża się emisja CO2. Natomiast dla tej samej ilości paliwa moc bloku wzrasta w porównaniu z układem bez odzysku. Większe efekty uzyskuje się w przypadku bloków spalających węgiel brunatny, co wynika z większej ilości spalin odlotowych z kotła oraz ich wyższej temperatury. Dlatego ilość ciepła, które można wykorzystać do podgrzania kondensatu, jest ok. 2 razy większa w porównaniu z blokiem o tej samej mocy na węgiel kamienny. Dobudowanie instalacji usuwania CO2 spowoduje znaczny spadek sprawności wytwarzania energii elektrycznej.

EN

Discussed is a positive influence of implementing the flue gas heat recovery on fuel consumption reduction in conditions of constant power capacity of the unit equal to 460 MW. Additionally, apart from fuel economy, emission of CO2 decreases while with the same level of fuel consumption the unit capacity increases in comparison with the no-recovery system. We can obtain better effects in case of brown coal-fired units that result from bigger amount of a boiler outlet gases and their higher temperature. That is why the amount of heat, that can be used to warm up the condensate, is approx. two times bigger in comparison with a hard coal-fired unit of the same power capacity. Additional application of the CO2 removal system will cause considerable reduction of electric energy production efficiency.

15

Rozpodihl tiskihv na vkhodih lokal'nogo vihdsmoktuvacha z kihl'cevim povihtroobmezhnikom

Zhukovs'kijj S. S., Dovbush O. M., Cheterbok A.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

|

2009

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z. 55 [267]

67-75

EN

The systems of local exhaust ventilation of existing industrial enterprises, as a result of their construction elements imperfection, work with large air flow rate that causes considerable power and financial expenses. It is possible to increase efficiency of pollutants output hood, e.g. by set of its construction by circular air distinctor. A purpose of work is determination of distributing of the field of surplus pressure in the suction zone of cylinder hood with circular air distinctor and also optirnization of its diameter. Investigations of hood with circular air distinctor has been carried out on an experimental installation at isothermal conditions. The diameter of air distinctor a was varied within the limits of (0 -;- 2,0) diameter D of hood inlet chink. The analysis of the obtained epures of surplus pressure certifies: due to application circular air distinctor, which is located in plane of output apperture in the hood construction area of hood sucktion increases; zone of sucktion and vacuum value are maximum at attitude of diameter of air distinctor toward the diameter of hood inlet chink a/D = 1,75.