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1

Design of high-speed permanent magnet machines

Gieras Jacek F.

Przegląd Elektrotechniczny

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2019

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R. 95, nr 12

1--8

EN

The actual trend in high speed electromechanical drives technology is to use permanent magnet (PM) brushless motors The following issues, which are essential in electromagnetic, mechanical and thermal design of high-speed PM brushless motors have been discussed: 1) main dimensions and sizing procedure, 2) mechanical requirements, 3) stator design guidelines including bad practices, 4) rotor design guidelines, 5) retaining sleeves (cans), 6) losses in the rotor, 7) thermal and cooling issues.

PL

We współczesnych napędach elektromechanicznych wysokiej prędkości stosowane są głównie silniki bezszczotkowe o magnesach trwałych. W artykule przedstawiono najważniejszcze problemy wystepujące w projektowaniu tych maszyn: 1) wymiary główne, 2) wymagania mechaniczne,3) projektowanie stojana z uwzględnieniem złych praktyk, 4) projektowanie wirnika, 5) tuleja nieferromagnetyczna wirnika, 6) straty w wirniku, 7) zagadnienia cieplne oraz chłodzenie.

2

Determination of regression formulas for key design characteristics of container ships at preliminary design stage

Abramowski T., Cepowski T., Zvolenský P.

New Trends in Production Engineering

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2018

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Vol. 1, Iss. 1

247--257

EN

This article presents regression equations to estimate container ship design characteristics based on the most up-to-date data and deadweight capacity, the number of containers and their combination at the preliminary design stage. These design formulas could have application for the estimation of key container ship characteristics such as: main ship dimensions, geometric parameters, main engine total power, ship velocity, final price and others. Regression equations were performed on the basis of IHS Maritime & Trade main container ship data built from 2005-2015. All equations presented in this paper could have practical application at the preliminary design stage and increase ship design theory development.

3

The use analysis of regression for preliminary determine the parameters of the design – exploitation of motor yachts

Bortnowska M.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2014

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nr 39 (111)

38--42

EN

The economic crisis initiated in 2007, has caused disturbance and a fairly a sharp drop the yachting industry in the country. Many of foreign companies could not bear at all the crisis and were forced to close or were absorbed by other companies in the sector. Since 2010, is observed the at first slow, and currently the dynamic growth of produced boats for various purposes also on the Polish market for Polish customers. The upward trend of the sector will need adequately trained engineers (specialists) - designers, constructors, technologists, etc. Deficiencies literature regarding (approaches) design guidelines on recreational boats, bowed the author to develop one of the methods determine the basic dimensional parameters and design of motor yachts at the initial stage, right away selected the technical assumptions. Based on the gathered database of built yachts developed regression that allow the initial design stage to determine the basic dimensions, namely: LOA, B, H, T and the design parameters, i.e. D, SP, CB yacht. This allows start the next project stage, which is the creation the first concept yacht along with his shape, bodylines and estimate construction costs.

4

Main dimensions selection methodology of the container vessels in the preliminary stage

Charchalis A., Krefft J.

Journal of KONES

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2009

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Vol. 16, No. 2

71-78

EN

TEU number which the container ship is designed for, directly influences the main hull dimensions that is displacement D, length L, breadth B, draught T, their combinations and block coefficient delta. The main dimensions have a great impact on developing the ships resistant performance. Thus, it is really fundamental to establish the correct dimensions of the hull during the design and ship building process. Estimating the shape of the ships hull, that comprises its main dimensions, is one of the basic tasks as part of the preliminary design stage. The most significant decisions determining ships performance, its duration and building costs are made at the beginning of the preliminary stage, before the contract is signed, when the costs are relatively low, up to 4.5% of total costs of technical and working stage. The results of the decision that has been made at the preliminary design stage are significant for the new building ship including its building costs and what is more important, for the ship owner, the ships operational costs. It is important to limit the total ship resistance, for instance, by lowering the wave ship resistance as much as possible, especially when the operational speed and TEU number carried by one vessel is increasing. That resistance depends on the operational speed expressed by Froude number. The resistance criteria and the existing hull dimensions limits, resulting from ships route, must be taken into consideration bearing in mind safety conditions such as ships stability and seaworthiness, when the main ships dimensions are being determined.

5

Main dimensions selection methodology of the container vessels in a preliminary stage

Charchalis A., Kreft J.

Journal of KONES

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2008

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Vol. 15, No. 4

89-97

EN

TEU number, which the container ship is designed for, directly influences the main hull dimensions that are displacement D, length L, breadth B, draught T, their combinations and block coefficient 8. The main dimensions have a great impact on developing the ships resistant performance. Any change in one of the main dimensions causes change in the value of the block coefficient 8 and influences the ship total resistance. Thus, it is really fundamental to establish the correct dimensions of the hull during the design and ship building process. Estimating the shape of the ships hull, that comprises its main dimensions, is one of the basic tasks as part of the preliminary design stage. The most significant decisions determining ships performance, its duration and building costs are made at the beginning of the preliminary stage, before the contract is signed, when the costs are relatively low, up to 4.5% of total costs of technical and working stage. The results of the decision that has been made at the preliminary design stage are significant for the new building ship including its building costs and what is more important, for the ship owner, the ships operational costs. It is important to limit the total ship resistance, for instance, by lowering the wave ship resistance as much as possible, especially when the operational speed and TEU number carried by one vessel is increasing. That resistance depends on the operational speed expressed by Froude number Fn. The resistance criteria and the existing hull dimensions limits, resulting from ships route, must be taken into consideration bearing in mind safety conditions such as ships stability and seaworthiness, when the main ships dimensions are being determined. The main dimensions and their relations concerned with the TEU number of the contemporary container carriers have been presented in the article along with selection methodology of ships main dimensions.

PL

Liczba kontenerów TEU (Twenty foot Equivalent Units) dla której zaprojektowany jest kontenerowiec bezpośrednio wpływa na główne wymiary kadłuba statku, w tym wyporność D, długość L, szerokość B, zanurzenie T, ich kombinacje i współczynnik pełnotliwości kadłuba 8. Główne wymiary mają duży wpływ na opór statku i rozwój jego osiągów. Jakakolwiek zmiana w każdym z głównych wymiarów powoduje zmianę współczynnika pełnotliwości kadłuba 8 i wpływa na całkowity opór statku. A zatem jest sprawą zasadniczą ustalenie właściwych wymiarów kadłuba w procesie projektowania i budowy statku. Oszacowanie kształtu kadłuba statku, na który składają się jego główne wymiary jest jednym z podstawowych zadań części wstępnej projektu. Najbardziej znaczące decyzje określające osiągi statku, czas budowy i jej koszty są podejmowane na początku etapu wstępnego, przed podpisaniem kontraktu, gdy koszty są jeszcze niskie, dochodzące do 4.5% całkowitych kosztów projektowych i wykonawczych. Rezultaty tej decyzji podjętej w fazie projektu wstępnego są znaczące dla nowobudowanego statku, wliczając w to koszty jego budowy i, co jest ważniejsze dla właściciela statku, jego koszty eksploatacyjne. Ważnym jest by ograniczyć opór całkowity kadłuba, przykładowo, przez ograniczenie oporu falowego kadłuba jak tylko jest to możliwe, szczególnie gdy prędkość eksploatacyjna i liczba TEU kontenerów zabieranych przez jeden statek rosną. Opór ten jest zależny od prędkości eksploatacyjnej, wyrażonej liczbą Frouda Fn. Kryterium oporu i istniejące ograniczenia w wielkości kadłuba wynikające z tras rejsów muszą być rozważone przy określaniu głównych wymiarów statku, biorąc pod uwagę warunki bezpieczeństwa takie jak stateczność statku i jego dzielność morska. Główne wymiary i zależności pomiędzy nimi dotyczące liczby TEU współczesnych kontenerowców zostały przedstawione w artykule, wspólnie z metodologią wyboru głównych wymiarów statku.