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1

Simulation features of the impeller in a centrifugal pump

Mykhailiuk Vasyl, Fafaley Oleh, Deynega Ruslan, Mosora Yurii

Mining Machines

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2022

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vol. 40, iss. 1

1--7

EN

To ensure the operability of machinery and equipment for the oil and gas industry, it is important to study their operation with subsequent improvement. This scientific work is devoted to highlighting the operation simulation of the impeller in a submersible centrifugal pump, because the pump itself is the main equipment in oil production. The main parts of a submersible centrifugal pump are its stages, consisting of an impeller and a guide vane. When the impeller rotates, a force interaction of the flow with the impeller blades occurs, while a pressure difference in the fluid flow on both sides of each blade arises. The pressure forces of the blades on the flow create a forced rotational and translational motion of the fluid, increasing its mechanical energy. It should be noted that the movement of fluid in pump sections is a rather complex process that is difficult to accurately describe analytically. However, today there are various computer programs (SOLIDWORKS FlowSimulation, ANSYS CFD, etc.) based on the finite volume method (FVM). To study the operation of a submersible centrifugal pump impeller, there has been built its threedimensional model. As a result of calculations, the distribution of pressure and velocity in the cross section of the impeller was obtained.

2

FEM numerical simulation of contact stresses between driving shaft and hub impeller of fuel pump

Wiater M., Chladek G., Żmudzki J.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 113, nr 1

13--21

EN

Purpose: The aim of the work was to test the contact stresses in the model system of the turbine hub cooperating with the fuel pump drive shaft. The hypothesis of the work was that, by means of FEA, it is possible to assess the contact stresses in the materials of the turbine hub and the fuel pump shaft during torque transmission. Design/methodology/approach: A turbine with fibre-reinforced polyphenylene sulphide (PPS) composite cooperating with a stainless steel shaft (X46Cr13/1.4034) in a commonly used D-flat shape joint was selected for the experimental research. To assess contact stresses, the CAD model (NX, Siemens) of the entire turbine was limited to the hub area. The drive shaft is supported in accordance with the bearing in the fuel pump, and the possibility of rotation about the axis along the length of the torque-producing magnet is taken away. The system was loaded with a torque of 200 Nmm on the turbine. The turbine hub and shaft were calculated, taking into account the phenomenon of contact detachment or slip at the value of the friction coefficient of 0.1. Findings: The pressure transmission area was found in the area at the edge of the flat surface D-flat and on the opposite side of the D-convexity. The contact stresses on the D-flat side reached values close to the composite strength. Research limitations/implications: The studies did not take into account the technological inaccuracies, thermal deformation, local material properties, and wear. The value of the friction coefficient was not measured in realistic conditions with fuel lubrication. Practical implications: FEA has been achieved, which allows to reduce the cost of experimental research. Originality/value: The proposed model allows for further studies of the influence of elasticity of various materials and structures on contact stresses in order to assess wear resistance.

3

The Influence of Optimization Parameters on the Efficiency of Aluminium Melt Refining by using Physical Modelling

Walek Josef, Michalek Karel, Tkadlečková Markéta

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 3

60--66

EN

The article describes the influence of optimization parameters on the efficiency of aluminium melt refining by using physical modelling. The blowing of refining gas, through a rotating impeller into the ladle is a widely used operating technology to reduce the content of impurities in molten aluminium, e.g. hydrogen. The efficiency of this refining process depends on the creation of fine bubbles with a high interphase surface, wide-spread distribution, the residence time of its effect in the melt, and mostly on the wide-spread dispersion of bubbles in the whole volume of the refining ladle and with the long period of their effect in the melt. For physical modelling, a plexiglass model on a scale of 1:1 is used for the operating ladle. Part of the physical model is a hollow shaft used for gas supply equipped with an impeller and also two baffles. The basis of physical modelling consists in the targeted utilization of the similarities of the processes that take place within the actual device and its model. The degassing process of aluminium melt by blowing inert gas is simulated in physical modelling by a decrease of dissolved oxygen in the model liquid (water).

4

Physical Modelling of Degassing Process by Blowing of Inert Gas

Michalek K., Tkadlečková M., Socha L., Gryc K., Saternus M., Pieprzyca J., Merder T.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 2

987--992

EN

This paper deals with the possibilities of using physical modelling to study the degassing of metal melt during its treatment in the refining ladle. The method of inert gas blowing, so-called refining gas, presents the most common operational technology for the elimination of impurities from molten metal, e.g. for decreasing or removing the hydrogen content from liquid aluminium. This refining process presents the system of gas-liquid and its efficiency depends on the creation of fine bubbles with a high interphase surface, uniform distribution, long period of its effect in the melt, and mostly on the uniform arrangement of bubbles into the whole volume of the refining ladle. Physical modelling represents the basic method of modelling and it makes it possible to obtain information about the course of refining processes. On the basis of obtained results, it is possible to predict the behaviour of the real system during different changes in the process. The experimental part focuses on the evaluation of methodical laboratory experiments aimed at the proposal and testing of the developed methods of degassing during physical modelling. The results obtained on the basis of laboratory experiments realized on the specific physical model were discussed.

5

Cavitation wear of pump impellers

Szala M., Łukasik D.

Journal of Technology and Exploitation in Mechanical Engineering

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2016

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Vol. 2, nr 1

40--44

EN

Cavitation is a common phenomenon in pump systems, negatively influencing their operating parameters and components such as impellers and, thus, causing considerable financial losses. This paper explains the problem of cavitation and cavitation erosion. The causes of cavitation in pump systems are analyzed. A selection of centrifugal pump impellers damaged by cavitation erosion are presented and examined. The authors also discuss ways of preventing cavitation and cavitation erosion in pump systems. Finally, relevant conclusions are drawn.

PL

Kawitacja w układach pompowych jest zjawiskiem powszechnym, oddziaływującym negatywnie na parametry pracy oraz podzespoły pomp np. wirniki, przyczyniając się do dużych strat finansowych. W pracy wyjaśniono pojęcie kawitacji i erozji kawitacyjnej. Przedstawiono przyczyny występowania kawitacji w układach pompowych. Scharakteryzowano przykłady uszkodzonych w wyniku działania erozji kawitacyjnej wirników pomp wirowych. Omówiono sposoby zapobiegania kawitacji i erozji kawitacyjnej w układach pompowych, oraz sformułowano adekwatne wnioski.

6

Analysis of forced spatial vibrations of a centrifugal pump impeller with axial forces balancing device

Zhulyov A., Martsinkovsky V., Kundera C.

International Journal of Applied Mechanics and Engineering

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2016

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Vol. 21, no. 3

737--750

EN

In this paper, a model of a pump impeller with annular seals and a balancing device, used as a combined support-seal assembly, is considered. The forced coupled radial, angular and axial vibrations of the rotor are determined with consideration of linearized inertial, damping, gyroscopic, positional and circulating forces and moments acting on the impeller from the side of the fluid flow in annular seals. The theoretical analysis is supplemented with a numerical example, the amplitude frequency characteristics are shown.

7

Technical aspects of a large size industrial process turbo compressor revamp

Świder P., Kozanecki Z., Graczykowski M., Kryłłowicz W.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 145

119--120

EN

Current paper describes several modernization aspects of the process 8MW air compressor and its driver. The main aim of revamp was to increase internal efficiencies of both compressor and turbine and increase the load of the compressor without additional Power consumption. The original pressure ratio was preserved. To meet these requirements a redesign of the flow path of both machines was necessary. Moreover, the turbine working conditions were changed from extraction-condensing to condensing. In terms of compressor, impeller blade redesign, adaptation of diffusers and Abradable seals application were a part of the scope. The revamp was completed in April 2014 with all the requirements met. The paper covers the general outline and a comparison of the original and modernized machine operating parameters, design and technical assumptions, but also describes some problematic issues which occurred during the realization of the project.

8

Homogenizacja oraz wytwarzanie suspensji czterołopatkowym mieszadłem nowej konstrukcji

Rieger F., Jirout T., Kuncewicz C., Ceres D.

Przemysł Chemiczny

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2013

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T. 92, nr 4

508-511

9

A study of CFD simulations of the flow pattern in an agitated system with a pitched blade worn turbine

Skocilas J., Fort I., Jirout T.

Chemical and Process Engineering

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2013

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Vol. 34, nr 1

39--49

EN

This paper presents a numerical analysis of an agitated fully baffled cylindrical vessel with a down pumping four blade worn or unworn pitched blade impeller (= 45[degrees] and 30[degrees]) under a turbulent flow regime. CFD simulations predict the pumping capacity of the system equipped by worn and unworn pitched blade impeller. Experimental data were taken from the authors’ previous work and compared with results of numerical computations. A good agreement with experimental data was obtained. The ensemble-average mean velocity field with worn and unworn impellers was computed. It follows from the simulation results that the wear rate of the impeller blade has a significantly negative effect on the velocity distribution in an agitated liquid. The greater the destruction of the worn blade, the higher is the deformation of the velocity field around the rotating impeller, with a simultaneous decrease in impeller pumping capacity.

10

State-of-the-art technologies of turbine blade machining by methods of creep feed grinding

Poletaev V. A.

Scientific Problems of Machines Operation and Maintenance

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2012

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Vol. 47, nr 2

37--42

EN

The paper highlights the modern method of high-performance machining of geometrically complex surfaces of gas turbine engine (GTE) blades, i.e. the method of creep feed grinding. This method is widely used to machine parts made of the difficult-to-get materials, e.g. the heat-resistant nickel alloys and the cobalt based alloys applied in the production of GTE parts. The grinding process under consideration is the main technological procedure to machine the geometrically complex surfaces of turbine blade roots. It is these surfaces that determine the precise position of blades on the wheels, and correspondingly in GTE rotors and stators. The cut-maps for blade root creep feed grinding are presented, including their detailed description and guidelines in terms of their application under production conditions subject to automated production and the employment of equipment manufactured by well-known companies.

11

Mieszalnik z przekładnią planetarną dla kompozytów światłoutwardzalnych

Boryga M., Graboś A., Fidut W., Kalbarczyk G., Stasiek A., Dzwonkowski J.

Przemysł Chemiczny

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2012

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T. 91, nr 8

1518-1522

PL

Przedstawiono wyniki badań symulacyjnych i fizykochemicznych oraz realizację techniczną stanowiska do wytwarzania kompozytów światłoutwardzalnych. Badania symulacyjne przeprowadzono dla klasycznego i zmodyfikowanego napędu mieszadła z przekładnią planetarną. Na zaprojektowanym i zbudowanym stanowisku z napędem zmodyfikowanym przeprowadzono proces mieszania kompozytu zgodnie z opracowaną procedurą. Badania właściwości fizykochemicznych uzyskanego kompozytu przeprowadzono zgodnie z normą PN-EN ISO 4049:2000. Zbudowane stanowisko z mieszalnikiem planetarnym oraz przedstawiona procedura mieszania wykorzystane zostały do wytwarzania kompozytów światłoutwardzalnych na skalę przemysłową.

EN

A process for mixing resins and fillers was simulated, 3D-modelled and implemented in an industrial scale mixer for production of light-cured resin-matrix composites for dentistry. The composites showed good mech. properties as well as low soly. and water absorption.

12

Analysis of the flow gas in a compressor impeller on the basis of velocity measurements with the use of LDA laser anemometer

Grzelczak M.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2011

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nr 140

73-82

EN

This study presents results of tests on the structure of gas flow through a compressing stage of a radial blower. The tests conducted used LDA laser anemometer enabling measurement of velocities in diversified geometries such as, among others, geometries of the compressor rotors. The presented measurement results relate to a half-open axial and radial rotor, for which velocity field s were obtained in two control cross-sections, i.e. in the inlet cross-section and outlet cross-section. The obtained results enabled an evaluation of the effectiveness of the adopted design solutions.

13

Effect of Exit Blade Angle, Viscosity and Roughness in Centrifugal Pumps Investigated by CFD Computation

Li W.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2011

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Vol. 15, No 1

21-41

EN

It has long been known that the exit blade angle plays a very important role in the performance of a centrifugal pump handling water or viscous oil. The effect of exit blade angle on the performance and flow of centrifugal pumps is usually investigated experimentally. However, due to the high cost and limited data that can be obtained by experiment, currently there is a great need for this effect to be studied numerically by means of computational fluid dynamics (CFD). At present, extensive comparisons between experiment and simulation regarding the performance of viscous oil and flow in centrifugal pumps with different exit blade angles are not available. Hydraulic performance and flow details in the impeller and the volute of a centrifugal pump with an exit blade angle of 44o were investigated numerically with the CFD code Fluent, using water and viscous oil as the working fluid, respectively. The effect of exit blade angle was then elucidated by comparing the performance and flow with that of a pump with an exit blade angle of 20o. It was determined that the results for the performance and flow obtained by means of CFD were in qualitative agreement with the observations. The sudden-rising-head effect is dependent on roughness and viscosity. The unstable zone in the theoretical head curve of the impeller at a low flow rate was attributed to the strong reaction of the volute to the flow in the vicinity of the impeller exit. The flow in the impeller with a large exit blade angle was subject to separation near the blade pressure side, however, a large exit blade angle helped improve the pump performance of viscous oil.

14

Modernizacja kotłowego wentylatora promieniowego bez demontażu wirnika

Beczkowski J., Jóźwik K.

Przegląd Mechaniczny

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2011

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nr 3

41-46

PL

Wentylatory kotłowe bardzo często cechują się niską sprawnością, wynikającą z nieprawidłowego doboru charakterystyki wentylatora do rzeczywistego punktu pracy. W artykule przedstawiono koncepcję modernizacji wentylatora kotłowego przez zmiany konstrukcyjne łopatek wirnika bez jego demontażu. Zmiany te poprzedzono badaniami modelowymi, które wykazały konieczność zmiany punktu pracy w układzie (p,V). Wykonano modernizację łopat wirnika, określając zmniejszenie kąta wlotowego (zastosowanie nakładki, tzw. noska, na część wlotową nakładek) oraz skrócenie średnicy zewnętrznej łopat (zaślepienie skróconych łopat połączeniem śrubowym z nakładką spływową).

EN

Low efficiency often characterizes boiler fans. It arises from incorrect selection of fan characteristic to real working point. There was presented idea of modernization of boiler fan by structural changes in impeller blades without impeller disas-sembly. Mentioned changes were preceded by modeling, which revealed necessity of working point change in (p, V) system. Modernization of impeller blades was performed, defined reduction of inlet angle (using of cover piąte "nose" on inlet part) blades outside diameter shortening (clogging of curtate blades by bolted joint with downflow plate).

15

Drgania samowzbudne i wymuszone układu sztywnego wirnika podpartego w łożyskach ślizgowych niekołowych smarowanych cieczą nienewtonowską

Starczewski Z.

Przegląd Mechaniczny

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2011

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nr 9

46-47

16

Wpływ oporów ruchu wirnika na sprawność pompy odśrodkowej

Rokita J.

Pompy, Pompownie

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2011

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nr 1 (140)

40-43

PL

Analiza strat wirowania tarcz i ich wpływu na sprawność pompy o małej szybkobieżności.

EN

Theoretical analysis of disc friction losses and their impact on efficiency of low-speed pumps.

17

Modyfikacja wirnika separatora cząstek stałych z zastosowaniem analizy MES

Michalczyk K., Salwiński J.

Mechanik

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2010

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R. 83, nr 1/S

164-171

PL

Przedstawiono analizę wytrzymałościową wirnika separatora cząstek stałych, poddanego obciążeniom wynikającym z rzeczywistych warunków pracy separatora. Obliczenia analityczne wykazały, że strumień powietrza i separowanych cząstek nie ma istotnego wpływu na wytężenie wirnika. Badania symulacyjne z użyciem MES pozwoliły na wskazanie stref koncentracji naprężeń oraz modyfikację parametrów geometrycznych wirnika, zapewniającą wymagany współczynnik bezpieczeństwa.

EN

This paper presents stress analysis of a solid particles separator. The analytical approximation of maximum stress level caused by radial acceleration revealed that stresses in working conditions may exceed the yield point of separator's material. The analytic calculations revealed that vibrations have marginal influence on state of stresses. Thus the FEM analysis was conducted to obtain more accurate results. Identification of most yielded areas let to perform proper modifications of separator's rotor, which allowed reduction of stresses much below yield point.

18

Flow characteristics of axial high speed impellers

Fort I., Kysela B., Jirout T.

Chemical and Process Engineering

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2010

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Vol. 31, z. 4

661-679

EN

The study deals with experimental investigation of the velocity field in the impeller discharge flow in a fully baffled cylindrical mixing vessel under turbulent regime of flow of agitated liquid. Four different axial high-speed impellers were tested. Laser Doppler anemometry was used for measurement of the radial profiles of the axial component of ensemble averaged mean velocity and the axial component of RMS fluctuating velocity just below the rotating impeller. Resulting velocity profiles were expressed by means of the main flow characteristics of investigated velocity field: flow rate criterion, total flow rate criterion and energetic efficiency of all four tested axial high-speed impellers.

19

Distribution of values of the volumetric mass transfer coefficient during aeration of liquid using a self-aspirating impeller

Kurasiński T., Kuncewicz C., Stelmach J.

Chemical and Process Engineering

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2010

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Vol. 31, z. 3

505-514

EN

The distributions of volumetric mass transfer coefficients (kLa) in a stirred tank with a self-aspirating disk impeller are presented in this paper. The highest values of (kLa) are attained in the region of tank wall, being by ca. 40% higher than the mean value in a whole stirred vessel.

PL

Przedstawiono rozkład lokalnych wartości objętościowego współczynnika wnikania masy (kLa) w mieszalniku z samozasysającym mieszadłem tarczowym. Największe wartości (kLa) . około 40% większe od wartości średniej dla całego mieszalnika . są osiągane w pobliżu ścianki mieszalnika.

20

The analysis of geometrical data preparation process of aircraft engines parts manufacturing with RP systems using

Budzik G

Silniki Spalinowe

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2009

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R. 48, SC1

295--300

EN

The article presents the analysis of data process preparation for Rapid Prototyping (RP) methods for manufacturing prototypes of aircraft engines parts (blade, gears, impellers). Physical model manufacturing using RP systems is possible on the basis of 3D-CAD models. The article presents an influence of CAD model parameters on geometrical accuracy of physical model. First part of the article presents CAD modeling method and errors of CAD modelling process. There are presented the results of CAD models errors analysis generated during data processing (conversion and export of geometrical data). Computer Aided Systems (e.g. Mechanical Desktop, CATIA V5R18, Unigraphics, Inventor, Solid Edge) allow to generate automatically Rapid Prototyping (RP) files (e.g. STL format) from their CAD models. STL file data is one of the most often used RP format to build a physical model. The methods of generation of correct STL model from Mechanical Desktop, CATIA V5R18, Unigraphics, Inventor, Solid Edge are presented. As a results of performed analysis the best way of geometrical data transfer from 3D-CAD models to CAM-RP environment was chosen. The results of analysis allowed to optimize virtual model from the physical and geometrical accuracy aspects. It is especially important for aircraft engines parst prototype manufacturing.

PL

Artykuł przedstawia analizę procesu przygotowania danych geometrycznych łopatki wirnika silnika lotniczego. Wytworzenie modelu fizycznego za pomocą metod szybkiego prototypowania (RP) jest możliwe na podstawie modelu 3D-CAD. W artykule przedstawione zostały czynniki mające wpływ na dokładność modeli 3D-CAD. W pierwszej części opisane zostały krótko sposoby modelowania wybranych elementów silnika lotniczego i możliwości powstawania błędów modelowania mających wpływ na dokładność prototypów. Następnie przedstawione zostały wyniki analizy błędów kształtu takich elementów jak koła zębate, łopatki, wirniki powstałe w wyniku przetwarzania i eksportu danych za pomocą najczęściej wykorzystywanych przez firmy branży lotniczej programów CAD tzn. Mechanical Desktop, CATIA V5R18, Unigraphics, Inventor, Solid Edge. Analizie poddane zostały moduły eksportu danych przedmiotowych programów do formatu STL. Format STL pozwala na wymianę danych pomiędzy systemami CAD a oprogramowaniem urządzeń RP. Format STL jest najpowszechniej stosowany jako format wymiany danych pomiędzy programami CAD/RE a programami sterującymi urządzeniami do szybkiego prototypowania. W wyniku przeprowadzonej analizy możliwe było określenie optymalnej ścieżki transferu danych pomiędzy środowiskiem 3D-CAD a środowiskiem CAM-RP. Wyniki analizy pozwoliły również na optymalizację modeli wirtualnych w aspekcie podwyższania dokładności prototypów fizycznych. Jest to szczególnie istotne w przypadku wykonywania prototypów o skomplikowanych kształtach takich jak elementy silników lotniczych.