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1

System wspomagania oceny stateczności przegubowych wozów wiercących

Bołoz Łukasz

Systemy Wspomagania w Inżynierii Produkcji

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2023

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Vol. 12, iss. 2

9--27

PL

Samojezdne maszyny górnicze takie jak kołowo-oponowe wozy wiercące charakteryzują się budową przegubową oraz wyposażone są w wysięgniki z organami roboczymi wysuniętymi daleko poza obrys podwozia. Taka konstrukcja powoduje, że maszyny te są podatne na utratę stateczności. Stąd też konieczne jest analizowanie rozkładu mas oraz ich szeroko pojętej stateczności podczas całego procesu projektowania, przy uwzględnienie wielu czynników wynikających ze sposoby i warunków ich pracy. Jednak brak jest odpowiednich modeli obliczeniowych pozwalających na przeprowadzenie badań analitycznych dla maszyn o takiej konstrukcji. W artykule przedstawiono autorski system wspomagający szybką ocenę stateczności jedno i dwuwysięgnikowych wozów wiercących. Model pozwala na przeprowadzenie analiz bez konieczności rozwiązywania równań różniczkowych występujących w modelach dynamicznych oraz bez stosowania badań modelowych za pomocą narzędzi CAD/CAE. Opracowany model obliczeniowy został zweryfikowany przez porównanie uzyskanych wyników z wynikami z pełnego modelu dynamicznego, z wynikami badań modelowych przeprowadzonych w programie CAD/CAE oraz z wynikami badań empirycznych nacisków kół i podpór na podłoże dla wybranego wozu wiercącego. Na podstawie weryfikacji i walidacji tego modelu stwierdzono jego pełną poprawność oraz przydatność. Model został wykorzystany do opracowania praktycznego i łatwego w obsłudze arkusza obliczeniowego. Następnie przeprowadzono badania analityczne stateczności wybranego wozu wiercącego. Model obliczeniowy jak i arkusz kalkulacyjny stanowią podręczne narzędzie wykorzystywane podczas procesu projektowania przez jedną z polskich firm produkujących wozy wiercące.

EN

Underground mining machines, such as wheel-tyre drilling rigs, are articulated and equipped with booms that project far beyond the undercarriage. Such a structure makes these machines prone to lose stability. Hence, it is necessary to analyse the distribution of masses and geometry as well as their broadly understood stability during the entire design process, taking into account many factors resulting from the manner and conditions of their operation. However, there are no ap-propriate computational models that would enable carrying out analytical tests for machines with this kind of construction. The article presents the author's support system which allows a quick assessment of the stability of single- and twin-boom drilling rigs. The model makes it possible to perform analyses without having to solve differential equations present in dynamic models or using model studies based on CAD/CAE tools. The developed computational model was verified by comparing the obtained results with the results of the full dynamic model, the results of model tests carried out in the CAD/CAE program and the results of empirical tests of wheel and jack pressures on the ground for the selected drilling rig. Based on the verification and validation of this model, it was found to be fully correct and useful. The model was used to prepare a practical and user-friendly calculation sheet. Next, analytical tests of the stability of the selected drilling rig were carried out. The computational model and the spreadsheet provide handy tools used during the design process by one of the Polish companies producing drilling rigs.

2

Badania pracy urządzenia regulacyjnego węzłów cieplnych bezpośrednich wykorzystywanego do zarządzania parametrami wody

Wołoszyn Jerzy, Zięba Paweł, Różycki Sławomir

Przemysł Chemiczny

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2023

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T. 102, nr 7

726--730

PL

Przedstawiono wyniki badań symulacyjnych pracy urządzenia regulacyjnego węzłów cieplnych bezpośrednich wykorzystywanych przez obiekty technologiczne i budynki posiadające przyłącza ciepłownicze bezpośrednie. Stwierdzono, że urządzenie może zapewnić wymagane temperatury w szerokim zakresie nastaw i przedstawiono wyniki dla wybranego przypadku.

EN

The operation of the control device of direct heating substations used by technol. facilities and buildings with direct heating connections was simulated using the OpenModelica program. It was found that the device can provide the required temp. in a wide range of settings. The results for a selected case were presented.

3

Cross-waves and pulsating flows in the side-channel spillway - an experimental approach

Azmeri Azmeri, Ummah Chairatun, Jemi Faris Zahran, Faudli Imam, Nasaiy Qurratul 'Aini Benti

Journal of Water and Land Development

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2023

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no. 56

51--57

EN

Potentially hazardous side-channels of complex geometry need to be investigated using detailed hydraulic physical models. This study aims to analyse the cross-waves pattern and pulsating flow using a side-channel spillway physical model. This study compares the cross-waves pattern were measured using an experimental installation set to generate cross-waves on the surface (original series) with another structure that did not produce cross-waves (modified series). The results showed that the geometry of the left wall caused instability in flow patterns and secondary flows. The starting point of Q2 discharge was detected by minor turbulence on the water surface near the left wall at a water depth of 3.3 m at the starting point of the wall, but with no overtopping. Cross-waves formed downstream at the right wall crosswise, lower than at the left wall. The height of the cross-wave increased substantially from Q100 to Q1000 discharges leading to overtoppings near the left wall at a water depths of 4.2 and 5.0 m at the starting point of the wall, and near the right wall at a water depths of 3.8 and 4.0 m at the upstream point of the wall. The modifications provided optimal hydraulic conditions, i.e. elimination of cross-waves and non-uniform flows. The Vedernikov and Montouri numbers showed that both original and modified series did not enter the area where the pulsating flow occurred. This indicated that both series were free from the pulsating flow.

4

Computer-aided selection of the stabilising system parameters of the mobile transport and assembly manipulator in mining excavations

Krauze Krzysztof, Klempka Ryszard, Mucha Kamil, Wydro Tomasz

Archives of Mining Sciences

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2023

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Vol. 68, no. 1

3--18

EN

Shifting masses in a confined space in the company of other machines and devices, which limits the manoeuvring and transport area, poses a significant problem in every field of industry, especially with underground mining. The works involved in transporting and manoeuvring masses in underground workings are challenging and are most often performed using various auxiliary machines or manually. Hence the need arose to develop a device carrying out activities related to the shifting of masses with the assumed maximum value. The device was created as a result of cooperation between FAMA sp. z o.o. and the AGH University of Science and Technology in Kraków, Poland. The mining modular transport and assembly unit (MZT-M) enables assembling and transporting various masses, especially the elements of the roadway support in the face. The primary function of this device is its movement in the excavation along with the transported mass and delivering it to a specific place. Therefore, an important issue is to ensure the module’s stability in different phases of its operation (lifting, transport, manoeuvring, feeding, lowering) due to the limited space in the excavation. That is why an analytical model and specialised software were created to determine the design parameters of the device as a function of its operating phases, especially the counterweight’s mass. As previously mentioned, an analytical model (physical, mathematical) with equations and applications written in Microsoft Visual Studio and Matlab was used for this purpose. It is beneficial at the design or construction changes stage. Calculation results are documented in the form of numerical summaries and graphs.

5

Optimal state feedback controller for balancing cube

Kowalczyk Adam, Piotrowski Robert

Journal of Automation Mobile Robotics and Intelligent Systems

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2022

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Vol. 16, No. 3

3--12

EN

In this paper, a nonlinear balancing cube system is considered, the concept for which is based on an inverted pendulum. The main purpose of this work was the modelling and construction of a balancing cube with the synthesis of the control system. The control objectives included swing-up and stabilization of the cube on its vertex at an unstable equilibrium. Execution of the intended purpose required, first, deriving a cognitive mathematical model. It was based on the Lagrange method. Next, a mathematical model for control purposes was derived. The project of the physical model of the balancing cube was presented. A stabilization system based on a linear quadratic regulator (LQR) was developed. Moreover, a swing-up mechanism was used to bring the cube close to the upper equilibrium point. The algorithm switching condition was important to enable the correct functioning of the system. The developed control system was verified in the Matlab environment. Finally, verifying experiments and comparisons among models (mathematical and physical) were performed.

6

Hydraulic jump and energy dissipation with stepped weir

Azmeri Azmeri, Basri Hairul, Yulianur Alfiansyah, Ziana Ziana, Jemi Faris Zahran, Rahmah Ridha Aulia

Journal of Water and Land Development

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2021

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no. 51

56--61

EN

Energy dissipator functions to dissipate the river-flow energy to avoid longitudinal damage to the downstream river morphology. An optimal energy dissipator planning is essential to fulfilling safe specifications regarding flow behavior. This study aims to determine the variation of energy dissipators and evaluate its effect on the hydraulic jump and energy dissipation. For this purpose, a physical model was carried out on the existing weir condition (two steps). It was also carried out on four stepped-weir variations, i.e., three-step, three-step with additional baffle blocks at the end sills, four-step, and six-step. Dimensional analysis was employed to correlate the different parameters that affect the studied phenomenon. The study shows a three-step jump shows a significantly higher Lj/y1 ratio, which is an advantage to hydraulic jumps’ compaction. The comparison of energy dissipation in all weir variations shows that the three-stepped weir has wasted more energy than other types. The energy dissipation increase of the three-step type is 20.41% higher than the existing type’s energy dissipation and much higher than other types. The dimensions of the energy dissipation basin are the ratio of the width and height of the stairs (l/h) of the three-step type (2.50). Therefore, this type is more optimal to reduce the cavitation risk, which damages the river structure and downstream area.

7

Experimental study of the effect of rock blasting with various cutting forms for tunnel excavation using physical model tests

An Huaming, Song Yushan, Yang Deqiang

Archives of Civil Engineering

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2021

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Vol. 67, nr 3

599--618

EN

Cutting blasting has been widely used for tunnel excavation. The cutting forms significantly influence the blasting effect. This research focuses on the study of the relationship between cutting forms and blasting effects. Similarity theory is proposed for the experimental study of the rock blasting using small models. Then four experimental modes with different cutting forms are used to study the blasting effect due to the cutting forms. The cutting depth, borehole utilization rate, fragments volume, and average fragment size are analysed. The blasting effects with various cutting forms are compared. The influences of the borehole space and the blasting delay are discussed. It is concluded that the spiral cutting form can produce more fragments and is recommend for the small section tunnel excavation.

8

Depositional styles and adjustment of channel cross sections in a seasonal deltaic system: a large scale physical experiment

Luo You, Zhang Hongbin, Zhu Senlin

Acta Geophysica

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2021

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Vol. 69, no. 6

2443--2452

EN

Small scale experiments provide limited mechanistic insight on the evolution of the cross-sections of the channel in a deltaic system. Here, we report the results of a large-scale tank experiment on the deltaic processes in a new river course into the Qinglan Lake. The depositional body occurred from upstream to downstream in the new river course in the depositional processes. Three depositional styles have been observed in the delta building: levee, stable-bar, and wandering-bar. Single thread and braided channels have been formed with deposits of levee style and stable-bar style. Wandering-bar style, which is an autogenic process, refers to the switching in the location of the main silting zones at different spatial–temporal scales and is frequently accompanied by avulsion, river braiding, and mainstream migration. The elevation of levees and bars increased to the bankfull elevation in the blocked river reach in the first 30~40 years and impacted the main channel flow. Comparing to the blocked river reach, the evolution of the bankfull elevation and geomorphic coefficient B0.5/H (B is width, H is water depth) of the cross-sections in the new reach indicates that the evolution pathways of the cross-sections could be divided into two stages: convergent stage and autogenic feedback stage. The convergent stage refers to a positive feedback loop, while the autogenic feedback stage is dominated by autogenic process. The present study shows the diversity of landforms, complex feedbacks and internal thresholds of a seasonal deltaic system, and the results provide another view on hydraulic geometry.

9

Mathematical modeling of the motion parameters of a disabled person in a bus

Chogovadze Jumber, Gogiashvili Phridon, Lekveishvili Gocha, Kbilashvili David, Mardaleishvili Nodar

Transport Problems

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2020

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T. 15, z. 1

49--59

EN

With a view to determining the dynamics and possible trauma sustained by a disabled person in a wheelchair in the passenger compartment of a bus, a physical model has been developed. The system, as the time function, generalized in the coordinates X(t), (t), was described by second-order Lagrangian differential equations. The proposed mathematical model allows for determining the motion characteristics of disabled people in a wheelchair in a bus that can cause injuries. This paper presents the curves of the change in coordinates of the angular velocity of the head and its center of gravity, as well as the curve of the change in the angle between the femur and the wheelchaior seat, through mathematical modeling and an experiment.

10

Procedury kalibracji i synchronizacji czujników oraz aparatury sterująco-pomiarowej w modelach fizycznych reaktorów metalurgicznych

Pieprzyca Jacek, Merder Tomasz

Hutnik, Wiadomości Hutnicze

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2020

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Vol. 87, nr 9

217--220

PL

Modelowanie fizyczne, jako technika badawcza zjawisk występujących w trakcie procesów przemysłowych, często rozumiane jest jako prowadzenie eksperymentów z wykorzystaniem modeli fizycznych urządzeń, w których te zjawiska zachodzą. Takie rozumowanie jest błędne. Modelowanie to proces składający się z wielu etapów, zarówno czysto abstrakcyjnych (koncepcyjnych), jak i technicznych. Proces modelowania rozpoczyna się w momencie podjęcia decyzji o jego zastosowaniu, a kończy wraz z uzyskaniem zadowalających rezultatów. Jednym z ważniejszych etapów procesu modelowania jest wybór adekwatnej do badań i stosowanych rodzajów znacznika aparatury pomiarowej, a w szczególności czujników pomiarowych. Ich synchronizacja i rzetelna kalibracja mają fundamentalny wpływ na jakość i rzetelność uzyskiwanych wyników badań. W artykule przedstawiono sposób realizacji tego etapu procesu modelowania, posługując się przykładem fizycznego modelu wodnego stanowiska pieca kadziowego.

EN

Physical modelling - a research technique for studying the phenomena occurring during industrial processes - is often only perceived as conducting experiments using physical models of devices in which these phenomena occur. Such perceptions are wrong though. Physical modelling is a process consisting of many stages, some purely abstract (conceptual) and some technical. The process commences by setting clear assumptions of its application; and concludes once these assumptions are met. An important stage of the modelling process is the careful selection of measuring equipment, in particular measuring sensors. The sensors’ synchronisation and precise calibration have a fundamental impact on the quality of the final results. This article presents a method of implementing the measuring sensors in the modelling process, using the example of a physical water model of a ladle furnace.

11

Diagnostyka pracy kadzi pośrednich stosowanych do odlewania wlewków płaskich i kwadratowych

Suchan Hanna, Baran Klaudia, Cwudziński Adam

Hutnik, Wiadomości Hutnicze

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2020

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Vol. 87, nr 1-2

17--21

PL

W artykule przedstawiono wpływ pracy kadzi pośredniej na jakość odlewanych w sposób ciągły stalowych wlewków płaskich i kwadratowych. Przeprowadzenie badań na modelu wodnym pozwoliło uzyskać krzywe RTD typu F, na podstawie których określono strefę przejściową tworzącą się podczas odlewania sekwencyjnego dwóch różnych gatunków stali. Efektem wykonania symulacji numerycznych w programie Ansys-Fluent było określenie rozmieszczenia wtrąceń niemetalicznych w ciekłej stali oraz ocena poziomu rafinacji stali w trakcie procesu ciągłego odlewania.

EN

The article presents influence of tundish work on slabs and blooms quality during continuous steel casting. Water model investigations gave Residence Time Distributions curves type F, which allowed to define the transition zone between two different grades of steel during the sequential casting process. The Ansys-Fluent computer program was used for numerical simulation of non-metallic inclusions behaviour in the liquid steel and for estimation of inclusions removal level from liquid steel during casting.

12

Effects of water intake layout along the wharf shoreline on ships

Kong Xian-wei, Ding Lei, Liu Hai-cheng, Qu Jing, Li Xiao-song

Polish Maritime Research

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2019

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nr 4

165--171

EN

The construction of a water intake along the wharf shoreline can realise the intensive and comprehensive utilisation of the shoreline. However, since the water intake will increase the lateral flow at the wharf and also the hydrodynamic forces on ships, it will bring risks to ships mooring and leaving. The effects of the water intake on ships are studied using a physical model, numerical model and standard formulas. The results show that it leads to an increase of the hydrodynamic forces acting on the ship when the standard formulas are used to calculate the forces without considering the water level difference between the two sides of the ship. The results of the physical model are closer to the real situation. Measures that can effectively reduce the influence of the water intake on ships are proposed by increasing the distance between the wharf front and the front of the water intake as well as the depth of the water inlet windows.

13

BIM – z pomocą współczesnej praktyce

Bujak Piotr

Nowoczesne Hale

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2019

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Nr 4

41--45

PL

Model informacyjny jako wizualna reprezentacja bazy danych BIM może bardzo korzystnie wpłynąć na przebieg przygotowania i realizacji inwestycji. Nawiązując do tradycyjnych metod warsztatu projektowego posługującego się modelami fizycznymi, model informacyjny ułatwia interpretację założeń projektowych, identyfikację problemów i stanowi bazę dla organizacji pracy wielobranżowego zespołu projektowego. Model informacyjny, wspierając proces wymiany informacji, może znaleźć szczególne zastosowanie w projektach obiektów wielkopowierzchniowych, o wysokim poziomie komplikacji technicznej i znaczącym ryzyku wystąpienia błędów na etapie koordynacji międzybranżowej.

EN

An information model as a visual representation of BIM database can have a significant impact on investment preparation and execution process. Referring to traditional methods of the designing practice relying on physical models, the information model makes the interpretation of designing decisions and problems identification easier and serves as a base for the cooperation of an interdisciplinary team. The information model, supporting the process of information exchange, can be particularly useful for designing large-area, technically complicated buildings, prone to communication and coordination errors.

14

Physico-mathematical model of complex heat exchange between an electric infrared radiant heating panel and the environment

Priymak Oleksandr V., Ocheretianko Mykyta D., Zabolotnyi Serhii S., Motrechko Oleh M.

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2019

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Vol. 8 Nr 1

9--17

EN

One of the main elements of heating systems is a heating device, whose construction is constantly being improved upon on thanks to the development of the science surrounding the materials’ physical and chemical properties of the working bodies, manufacturing and application technologies. This article is devoted to the development of a physical model of complex heat exchange between an electric infrared radiant heating panel based on an amorphous metallic radiating plate located in the middle of the panel and surrounding solids and air. The developed physical model is described by mathematical equations taking into account the boundary conditions of the third kind on the basis of complex heat exchange by radiation and convection both with surrounding solid bodies and passing airflow. The purpose of the solution is to determine the rational relation between the radiation and convective components of heat transfer, depending on the comfortable state of the person (observance of the technological process), and the operating modes of the heating system.

PL

Jednym z głównych elementów systemów grzewczych jest urządzenie grzewcze, którego konstrukcja jest stale udoskonalana dzięki rozwojowi wiedzy w zakresie fizycznych i chemicznych właściwości materiałów, stosowanych technologii i sposobów produkcji. Artykuł poświęcony jest opracowaniu fizycznego modelu złożonej wymiany ciepła między elektrycznym promiennikiem podczerwieni, w którym zastosowano amorficzną metalową płytę promieniującą, umieszczoną na środku panelu. Opracowany model fizyczny opisano równaniami matematycznymi uwzględniającymi warunki brzegowe trzeciego stopnia przy założeniu złożonej wymiany ciepła przez promieniowanie i konwekcję zarówno z otaczającymi ciałami stałymi, jak i przepływającym powietrzem. Celem analizy jest określenie udziału promieniowania i konwekcji w wymianie ciepła, a także zależności między wymianą ciepła a warunkami komfortu cieplnego poszczególnych osób (uwzględniając przestrzeganie procesu technologicznego) oraz trybów pracy systemu grzewczego.

15

Physical model of power circuit of three-phase electric arc furnace

Wciślik M., Strząbała P.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 4

103--106

EN

The paper deals a model of the circuit arc furnace designed for electrotechnology or fundamentals of electrical engineering laboratory. This model works at low currents, without high temperature components. In this way, the cooling and dissipation of energy are avoided. This model allows the study of the impact of the supply system restrictions, reactive power compensation problems, harmonic propagation in the system and characteristics verification designated analytically or by simulation.

PL

W pracy przedstawiono model obwodu pieca łukowego przeznaczony do laboratorium elektrotechnologii lub podstaw elektrotechniki. Model ten pracuje przy niskich prądach, bez elementów o wysokiej temperaturze. W ten sposób unika się układów chłodzenia i rozpraszania energii. Umożliwia on badanie wpływu ograniczeń układu zasilania, problemów kompensacji mocy biernej, generacji harmonicznych w systemie oraz weryfikację charakterystyk wyznaczanych analitycznie lub symulacyjnie.

16

Opracowanie ceramicznego wymiennika ciepła z węglika krzemu

Perkowski Krzysztof, Gizowska Magdalena, Piątek Milena, Osuchowski Marcin, Witosławska Irena, Kalinowski Wojciech, Głodek-Bucyk Ewa, Sładeczek Franciszek

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2018

|

R. 11, nr 33

49--61

PL

Odzysk tzw. ciepła niskotemperaturowego wymaga specjalnych rozwiązań konstrukcji wymienników. W ramach działalności statutowej ICIMB podjęto prace nad opracowaniem ceramicznego wymiennika ciepła, którego powierzchnie robocze będą odporne na agresywne działania par i skroplin, a wskaźniki jakościowe procesu wymiany ciepła zapewnią wysoką efektywność procesu. W artykule przedstawiono wyniki badań właściwości materiału ceramicznego, założenia projektowe konstrukcji oraz pierwsze doświadczenia z realizacji modelu fizycznego wymiennika, a zwłaszcza formowania, spiekania i łączenia powierzchni wykonanych z węglika krzemu (SiC).

EN

The recovery of the low-temperature heat requires special solutions of heat exchangers. As part of the statutory activities of ICIMB works have been carried out to develop a ceramic heat exchanger, which working surfaces will be resistant to aggressive vapor and condensates. The quality parameters of the heat exchange process should ensure high efficiency of the process. The paper presents the results of research on the properties of the ceramic material, the design assumptions and the first experiments on the implementation of the physical model of the heat exchanger, in particular forming, sintering and joining surfaces made of silicon carbide (SiC).

17

A physical model of energetic processes in a diesel marine generator set

Kniaziewicz T., Zacharewicz M.

Combustion Engines

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2018

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R. 57, nr 4

10--17

EN

The paper presents a physical model of energy related processes taking place in a diesel marine generator set. The development of a physical model was preceded by an analysis of the design structure of the investigated object and the flow of parameters among the functional modules of the model object. The above was completed by developing of functional and topological models. Only their analysis allowed the development of the proper physical model.

18

Comparison of GA-Optimized Viscoelastic Models for the Characterization of Compression Behavior of Warp-Knitted Spacer Fabrics

Yousefpour M., Ahmadi M. S., Payvandy P.

Autex Research Journal

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2018

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Vol. 18, no. 3

209--215

EN

Nowadays, Warp-Knitted Spacer Fabrics (WKSF) have been widely used for many technical applications. Compressional behavior of WKSF is one of their important properties. Physical modeling is one of the solutions to predict these properties for engineered designing of WKSF. In this study, four common physical models are introduced and compared in order to simulate compressional behavior of polyester WKSF. Genetic Algorithm (GA) was applied to optimize each model parameter. The results showed that the Burger model has the highest adoption with 0.2 percent Mean Absolut Error (MAE). The effect of thickness, outer fabric structure and spacer monofilament density on viscoelastic properties of the samples were also studied.

19

Physical model of energetic processes in the marine diesel engine

Bogdanowicz A., Kniaziewicz T., Zacharewicz M.

Zeszyty Naukowe Akademii Marynarki Wojennej

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2017

|

R. 58 nr 4 (211)

5--12

EN

The paper describes the preliminary physical model of gas-dynamic processes that take place in the cylinder of marine diesel engine. The model is a part of the work undertaken at the Institute for Construction and Exploitation of Ships at the Polish Naval Academy. The physical model is the basis for the development of a mathematical model of marine diesel engine, which will be useful for determining the energy efficiency of Polish ships, as well as for diagnostic purposes.

PL

W artykule opisano model fizyczny procesów gazodynamicznych zachodzących w cylindrach okrętowego tłokowego silnika spalinowego o zapłonie samoczynnym. Prezentowany model powstał w wyniku prac badawczych prowadzonych w Instytucie Budowy i Eksploatacji Okrętów Akademii Marynarki Wojennej. Stanowi on podstawę do opracowania modelu matematycznego, który znajdzie zastosowanie w badaniach nad efektywnością energetyczną siłowni okrętowej oraz będzie użyteczny w opracowywanych w Instytucie bezinwazyjnych metodach diagnostycznych silników okrętowych.

20

The analysis of factors influencing the dynamics of lowland riverbed erosion downstream of the Jeziorsko reservoir dam (central Poland)

Smaga A., Wierzbicki J., Wierzbicki M., Hämmerling M., Radaszewski R.

Geological Quarterly

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2017

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Vol. 61, No. 4

926--933

EN

Increased riverbed erosion could recently be observed in close vicinity of hydrotechnical constructions in many lowland rivers. The immediate effect of erosion in this case is a very significant reduction of the riverbed level over a considerable distance, downstream of large reservoir dams. This process is influenced simultaneously by both hydraulics of river flow and geotechnical properties of soil eroded. The paper presents an analysis of parametric changes in the level of river bottom and grain size of bed material, and the relative density in the context of changes in hydrological conditions and diversity of engineering-geological conditions. As the result, a multiparametric model of erosional potential of riverbed sediments has been proposed, which can significantly help in proper planning of locations and construction of correction thresholds under given hydraulic conditions of the river.