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1

Boundary layer tripping on a transonic compressor profile

Joseph A., Piotrowicz M., Flaszynski P., Doerffer P., Kaczynski P.

Archives of Mechanics

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2024

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Vol. 76, nr 5

451--470

EN

The numerical and experimental investigation of boundary layer tripping using steps on the suction side of a transonic compressor rotor has been presented in this paper. The presented research corresponds to an EU project known as TFAST (Transition Location Effects on Shock Wave Boundary Layer Interaction). A representative single passage test section has been designed to investigate the SBLI (Shock wave Boundary Layer Interaction) effects on the rotor profile. The geometrical and inflow boundary conditions have been defined by the project partner RRD (Rolls-Royce Deutschland). Two locations of step (x=c = 0:16 and x=c = 0:02) were chosen upstream of the shock location to investigate the boundary layer tripping effects and are compared with configuration without tripping setup. The numerical simulations were carried out on the test section model using the steady-state Reynolds Averaged Navier–Stokes (RANS) model with Explicit Algebraic Reynolds Stress Model (EARSM) turbulence model with transition effects included. The chosen turbulence model could accurately predict the shock location on the suction side of the lower profile in the test section and had a good agreement with wall pressure measurements using pressure taps. A detailed shock structure was captured using the schlieren technique and compared for different tripping configurations. To estimate the effectiveness of the tripping setup losses have been estimated using LDA (Laser Doppler Anemometry) along the traverse downstream the blade passage. To understand the tripping effect on the boundary layer a detailed investigation has been carried out at ten selected traverse locations from leading edge to trailing edge of the rotor profile. Based on the experimental validation of the defined numerical model for tripping setup, a few more step heights were compared at selected tripping locations numerically. To analyse the effect of step heights, the isentropic Mach number and wall shear stress are compared with without tripping configuration. The wake and stagnation pressure losses downstream of the profile have been compared to investigate the sensitivity of location and geometrical definition of the boundary layer tripping setup on the aerodynamic losses.

2

An investigation of hot spot location at turbine inlet – numerical simulations for factor project test rig

Flaszyński P., Piotrowicz M.

Transactions of the Institute of Fluid-Flow Machinery

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2017

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nr 135

101--115

EN

The main objective of the presented paper is the investigation of a ﬂow structure and parameters distribution downstream of combustor simulator and its eﬀect on turbine inlet. The investigations are carried out by means of numerical simulations for combustor and turbine nozzle guide vane conﬁguration existing at test rig in DLR Goettingen. As the eﬀect, the hot spot location for diﬀerent relative positions of the swirler and nozzle guide vanes is shown. The presented results are obtained within a pre-test simulations supporting the ﬁnal design of the test section and they allow to draw conclusions for the required limiting cases investigated experimentally. The location of the hot spot is highly important for thermal loading of the ﬁrst stage rotor.

3

Wprowadzanie wyrobów budowlanych do obrotu według systemu krajowego i europejskiego

Piotrowicz M., Łaskawiec K., Romanowski P.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2016

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R. 9, nr 25

35--43

PL

Wszystkie wyroby budowlane przed wprowadzeniem do obrotu podlegają procedurom oceny zgodności wynikającym z Rozporządzenia Parlamentu Europejskiego i Rady nr 305/2011. Ocena i weryfikacja stałości właściwości użytkowych wyrobów budowlanych w odniesieniu do ich charakterystyk jest przeprowadzana zgodnie z jednym z pięciu systemów określonych w tym rozporządzeniu. Wymagania dotyczące właściwości użytkowych zawarte są w normach zharmonizowanych, które określają system oceny i weryfikacji właściwości użytkowych dla danego wyrobu i wymagania związane z tym systemem. Normy te podlegają weryfikacji w pięcioletnich okresach. W prezentowanym artykule skonfrontowano aktualne wymagania dotyczące wprowadzania wyrobu do obrotu z wcześniej obowiązującymi.

EN

All constructions products before place on the market are subject to conformity assessment procedures resulting from Regulation (EU) No 305/2011 of the European Parliament and of the Council. Construction products must have a certain performance (essential characteristics) to allow designers/authorities to verify that construction works satisfy the Essential Requirements as regulated by each Member State in its territory. EU Commission invites CEN through mandates for specific product families to elaborate harmonized European standards for construction products. These standards are subject to verification in five-year periods. AVCP system (previously called „Attestation of Conformity”) foresees five systems defined in Directive. In this paper confronted current requirements for placing the product on the market with pre-existing.

4

Technologie bezwykopowe na sześciu kontynentach, cz. 11

Kubicka U., Piotrowicz M.

Nowoczesne Budownictwo Inżynieryjne

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2016

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Nr 1

32--36

PL

W cyklu Technologie bezwykopowe na sześciu kontynentach, przygotowanym razem z Polską Fundacją Technik Bezwykopowych, prezentujemy zakres tematyki, jaka została przedstawiona w czwartym numerze magazynu „Trenchless International” w 2015 r.

EN

In the cycle on Trenchless technologies on six continents being prepared together with the Polish Foundation for Trenchless Technology, we present the range of subjects presented in the fourth issue of the Trenchless International magazine in 2015.

5

Zastosowanie sieci Petriego do modelowania procesów bezpieczeństwa w transporcie morskim

Miler R. K., Piotrowicz M.

TTS Technika Transportu Szynowego

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2015

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R. 22, nr 12

1077--1083, CD

PL

Bezpieczeństwo transportu morskiego jawi się jako istotny czynnik sprawności oraz efektywności procesów realizowanych globalnie przy użyciu tej gałęzi transportu. Celem badań przedstawionych w niniejszym artykule było ukazanie możliwości wykorzystania różnorodnych notacji do modelowania wybranych procesów z zakresu bezpieczeństwa transportu morskiego. Szczególny nacisk położono na ukazanie możliwości zastosowania sieci Petriego jako nowatorskiej, dotychczas nie wykorzystywanej notacji dla reprezentacji opisywanych procesów. Do opisu wybrano reprezentatywny proces tworzenia zintegrowanego zobrazowania żeglugi (IMAP) z wykorzystaniem narzędzi monitoringu (podsystem sensoryczny), analizowania (podsystem analityczno-decyzyjny) oraz reagowania (podsystem efektorowy). W badaniu użyto analizy holistycznej w ramach paradygmatu cybernetycznego oraz wykorzystano metody i narzędzia modelowania z teorii systemów. Rezultatem badań jest przedstawienie procesu two-rzenia i analizy IMAP za pomocą schematów blokowych, algorytmów i sieci Petriego. Pozwoli to na dalsze prace związane z tworzeniem systemów eksperckich (analityczno-decyzyjnych) możliwych do implementacji w nowobudowanych zintegrowanych systemach monitoringu żeglugi morskiej i bezpieczeństwa transportu morskiego. W artykule pozytywnie zweryfikowano roboczą hipotezę stanowiącą, iż sieci Petriego stanowią użyteczną notację do modelowania i formalnej analizy procesów bezpieczeństwa transportu morskiego.

EN

Safety and security of maritime transport have become a significant element of recent global seaborne trade processes. The main aim of presented in this article research results is presentation of various notations that can be adopted for modelling of maritime transport security and safety processes. The main focus was on recognition of Petri nets as an innovative tool for modelling. Integrated Maritime Picture (IMAP) has been chosen for further detailed research as a representative process consists of monitoring (sensor process), analysis and reaction (effector process). As research methods a holistic analysis from cybernetic paradigm as well as modelling tools have been applied. Results come with presentation of the IMAP process with use of block schemes, algorithms and Petri nets. It may be further utilised in expert systems being the important part of already introduced integrated shipping monitoring systems. In this paper the working hypothesis stated that Petri nets are useful tool in maritime transport processes modelling has been proved.

6

Influence of limiting walls on shock wave structure in single passage test section with compressor profile

Piotrowicz M., Flaszyński P., Szwaba R.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 2

141--152

EN

The shock wave boundary layer interaction on the suction side of a transonic compressor blade is one of the main objectives of the TFAST project (Transition Location Effect on Shock Wave Boundary Layer Interaction). In order to look more closely into the flow structure on the suction side of the blade, a design of a turbine passage model in a rectilinear transonic wind tunnel was proposed. The model which could reproduce the flow structure, the shock wave location, the pressure distribution and the boundary layer development similar to the obtained in a reference cascade profile is the main objective of the design presented here. The design of the proposed test section is very challenging, because of the existence of a shock wave, its interaction with the boundary layer and its influence on the 3-D flow structure in the test section. The paper presents the influence of the test section geometry configuration on the flow structure as an effect of the shock wave boundary layer interaction.

7

Potencjał sekwestracyjny CO2 w betonach kruszywowych

Łaskawiec K., Piotrowicz M., Romanowski P., Woyciechowski P.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2015

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R. 8, nr 21

22--30

PL

Oddziaływania dwutlenku węgla na efekt cieplarniany są jednym z głównych zagadnień związanych z ochroną środowiska. Dwutlenek węgla występuje w atmosferze ziemskiej przy standardowej temperaturze i ciśnieniu. Spalanie paliw kopalnych i wycinki lasów to główne działania człowieka, które przyczyniają się do wzrostu stężenia dwutlenku węgla na ziemi. Emitery dwutlenku węgla to naturalne gorące źródła, wulkany, gejzery i rośliny. Ponieważ globalne ocieplenie stało się jednym z najważniejszych problemów, podejmuje się prace badawcze mające na celu rozwój technologii, które będą wspierać redukcję stężenia CO2 w atmosferze. Większość badań związanych z karbonatyzacją ograniczają się do jego wpływu na korozję stali zbrojeniowej i przewidywania żywotności konstrukcji żelbetowych. W artykule przedstawiono badania mające na celu określenie potencjału sekwestracji CO2 dla różnych odmian betonów wraz ze szczegółową analizą tego procesu.

EN

The carbon dioxide impact on the greenhouse effect is one of the major topics related to environmental protection. Carbon dioxide occurs in the Earthatmosphere at standard temperature and pressure. Combustion of fossil fuels and forest felling are the major human activities which contribute to concentration of carbon dioxide in the Earth atmosphere. The natural carbon dioxide emitters include volcanoes, hot springs, geysers and plants. Since the global warming became one of the most important issues, it calls for development of technologies which will support the reduction of the CO2 concentration in the atmosphere. Most of studies related to the carbonation are limited to its effects on corrosion of steel reinforcements and service life prediction of reinforced concrete structures. The article objective consists on determining the CO2 sequestration potential for different varieties of concrete together with a detailed analysis of this process.

8

Prefabrykaty - wprowadzenie wyrobu do obrotu

Łaskawiec K., Piotrowicz M.

Mosty

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2015

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nr 1

38--41

PL

W artykule skonfrontowano aktualne wymagania odnośnie wprowadzania wyrobu do obrotu z wcześniej obowiązującymi. Większość produkowanych prefabrykatów betonowych objęta jest systemami: 2+, 3, 4. W dalszej części artykułu przedstawiono wymagania związane z zasadami wprowadzania do obrotu na przykładzie niżej wymienionych elementów prefabrykowanych: nadproży i kanałów odwadniających (system 3), belek stropowych, płyt kanałowych, płyt zespolonych Filigran (system 2+), studni, rur (system 4).

9

Zastosowanie autoklawizowanego betonu komórkowego z recyklingu do wytwarzania betonu zwykłego

Łaskawiec K., Piotrowicz M., Zając P.

Materiały Budowlane

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2015

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nr 12

49--50

10

Ocena wpływu klasy pielęgnacji na wybrane właściwości eksploatacyjne betonu

Woyciechowski P., Piotrowicz M.

Materiały Budowlane

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2014

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nr 2

14--16

11

Choosing size of photovoltaic array for low feed-in tariffs

Marańda W., Piotrowicz M.

International Journal of Microelectronics and Computer Science

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2014

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Vol. 5, nr 3

92--97

EN

After several decades of gradual progress, the photovoltaics (PV) is reaching the economical feasibility and various incentives for its development are being cut. The most successful incentive - the feed-in tariff for photovoltaics - is being reduced in many countries. When feed-in tariff is lower than the purchase tariff, the beneﬁts of having a PV-system are shifting from selling energy to self consumption of PV energy. In tis case, however, the proper choice of PV-arrays size is not trivial and depends also on the owner self-consumption pattern. The paper investigates the sizing of PV-system for a several types of self-consumption with feed-in tariffs lower than purchase tariffs. The calculations are performed for a full year period with recorded irradiance data. The use of optional short-term energy storage has also been investigated. The calculations have been preformed for several feed-in vs purchase tariff ratios and consumption proﬁles.

12

Efficiency of maximum power point tracking in photovoltaic system under variable solar irradiance

Marańda W., Piotrowicz M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 4

713--721

EN

Field conditions decrease the energy output of photovoltaic (PV) systems, mainly due to excessive temperatures. However, in regions with moderate ambient temperatures, as in Poland, solar energy is commonly delivered with highly fluctuating irradiance. This introduces yet another source of energy losses due to the non-ideal tracking of actual position of Maximum Power Point (MPP). Majority of PV-systems are equipped with DC/AC and grid-connected inverter. Since the solar energy flux is variable, an adequate MPP-tracking algorithm is required to handle a wide range of load levels and face rapid changes of input power. Along with the essential DC/AC conversion, the quality of MPP-tracking must also be taken into account in evaluation of inverter efficiency. The tracking in dynamic conditions has been addressed only recently. Several algorithms has been studied theoretically, experimentally or in laboratory conditions by applying artificial input test-patterns. This work takes the opposite approach by applying the recorded real-life solar irradiance and simulating the tracking behavior to study the problem for true field conditions in Poland. The simulation uses the unique high-quality irradiance data collected with 200 ms time resolution. The calculation of both static and dynamic MPP-tracking efficiency has been performed for representative variable-cloudy day, applying commonly used Perturb&Observe tracking algorithm.

13

Klasy pielęgnacji betonu według PN-EN 13670:2011 – kryteria wyboru i wpływ na kształtowanie właściwości betonu

Piotrowicz M., Romanowski P., Woyciechowski P.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2013

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R. 6, nr 14

27--40

PL

Świeży beton powinien być pielęgnowany tak, aby zminimalizować skurczliwość plastyczną oraz zapewnić odpowiednią wytrzymałość i trwałość strefy powierzchniowej. Prawidłowa pielęgnacja jest warunkiem koniecznym do zapewnienia trwałości betonu. Celem prowadzonych badań było określenie wpływu przyjętej, zgodnie z normą PN-EN 13670:2011, klasy pielęgnacji betonu na właściwości związane z jego przypowierzchniową strukturą.

EN

Fresh concrete should be cured so as to minimize plastic shrinkage and ensure adequate strength and durability of the surface zone. Proper concrete curing is necessary to ensure the sustainability of concrete. The aim of the research was to determine the effect adopted in accordance with PN-EN 13670:2011, class of concrete curing on the characteristics associated with the subsurface structure.

14

Static and dynamic MPP-tracking efﬁciency of PV-inverter using recorded irradiance

Marańda W., Piotrowicz M.

International Journal of Microelectronics and Computer Science

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2013

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Vol. 4, nr 4

181--185

EN

This paper investigates the energy losses introduced by Maximum Power Point Tracking operation of photovoltaic (PV) inverter. In contrast to other studies, this evaluation has been done with the recorded real-life solar irradiance data applied to the simulation of the PV-generator and tracking algorithm. The true MPP output of photovoltaic generator has been calculated with electro-thermal model and the simulation has been carried out with 1 s time resolution. The efﬁciency results have been presented for both static and dynamic MPP-tracking investigated With basic and simpliﬁed Perturb&Observe algorithm with several tracking speed rates. In addition to the simulation, the inverter efﬁciency measurements for ﬁeld- installed inverter have been presented.

15

Prefabrykowane studnie kanalizacyjne i rury WIPRO z betonu modyfikowanego polimerami

Jelska K., Piotrowicz M., Zapotoczna-Sytek G.

Materiały Budowlane

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2012

|

nr 10

8-10

EN

The report presents course of work to establish recipe of concrete modified with tree kinds of polymers (in two levels of dosage) with the use in production of element of sewerage well and „Wipro” tubes with integrated gasket. The results of research proved, that polymers modification of concrete increased compression strength and bending strength, decrease of absorptivity, increase freeze resistance and decrease penetration of water under pressure.

16

Software Platform for Combined Analysis of Weather Data and Holter Monitoring Data

Kotas R., Kamiński M., Mazur P., Cieślik-Guerra U., Sakowicz B., Marańda W., Piotrowicz M., Kurpesa M., Napieralski A. A.

International Journal of Microelectronics and Computer Science

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2012

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Vol. 3, nr 4

159-164

EN

This paper presents the concept of computing software platform that allows for simultaneous analysis of weather and Holter signals. The first part of this paper describes the weather station and the software platform that is currently being developed. The second part of the article presents examples of preliminary analysis that can be performed using the software platform.

17

Hybrid Daytime Lighting System with Photovoltaics and Short-term Storage

Marańda W. W., Piotrowicz M.

International Journal of Microelectronics and Computer Science

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2012

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Vol. 3, nr 1

15-20

EN

Most efficient utilization of electrical energy takes place when energy is consumed locally, avoiding its distribution over long distances or costly storage technologies. Finding such applications for renewable energy sources, like wind or solar, is difficult. The main obstacle is the their limited predictability and the mismatch between energy availability and demand. Nowadays the daytime lighting in modern urban architecture causes a considerable electricity consumption. For such applications, there exists an excellent match between energy availability (solar irradiance) and consumption demand (interior illumination). Moreover, the demand can be met with relatively small PV-generators with modern energy efficient lighting technology. In this paper a hybrid lighting system for daytime, using both natural and artificial light, has been proposed. The supply for artificial lighting is provided from photovoltaic (PV) system or the utility grid, when solar irradiance cannot meet the illumination and electricity demand. The paper presents the results of simulation of full year energy savings in a daytime lighting system. The system maintains the indoor illumination level to be equal or higher than required by the norms, using natural sunlight and artificial lighting. The artificial lighting is used only to compensate the deficiencies of sunlight and is powered with autonomous PV-system in the climatic conditions of Central Europe. The PV-system is also equipped with short-term energy storage, based on super capacitor, allowing for only several minute of backup supply. Such storage is used only to mitigate the rapid solar power fluctuations, providing energy from PV supply at more stable power level during the day, but the excess of energy is not fed to the utility grid. The numerical simulation is using the solar irradiance data collected with 5 s time resolution during the whole year 2010 at Lodz University of Technology, in center of Poland.

18

Introducing thermal inertia in photovoltaic module simulation

Piotrowicz M., Marańda W.

Elektronika : konstrukcje, technologie, zastosowania

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2012

|

Vol. 53, nr 7

70-73

EN

Performance of photovoltaic systems greatly depends on climate conditions. Apart from values of solar radiation and ambient air temperature, highly varying radiation can also have an influence on energy yield from a PV-system. In less favourable climate conditions (e.g. in central Europe), highly varying radiation is very frequent and the accurate energy yield predictions from PV-systems require introducing thermal inertia into photovoltaic module thermal models. The presented paper demonstrates the simulation of the simple RC-thermal model of photovoltaic module. Long time period data from measurements of field-installed PV-system is utilized in module temperature calculations.

PL

Wydajność systemów fotowoltaicznych ściśle zależy od warunków klimatycznych. Oprócz temperatury otoczenia oraz wartości promieniowania i słonecznego, na uzysk energii wpływa także zmienność nasłonecznienia. W mniej korzystnych warunkach klimatycznych (np. w Europie Środkowej) ; szybkie zmiany natężenia promieniowania słonecznego obserwowane są bardzo często. W tej sytuacji, chcąc dokładnie prognozować uzysk energii z systemu fotowoltaicznego, w termicznych modelach modułów należy i uwzględnić wpływ inercji termicznej. W artykule przedstawiono symulację prostego termicznego modelu RC modułu fotowoltaicznego. Do obliczania temperatury paneli użyto danych z długookresowych pomiarów prowadzonych w rzeczywistym systemie.

19

Energy saving by compensation of daylight deficiencies in buildings

Piotrowicz M., Marańda W.

International Journal of Microelectronics and Computer Science

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2011

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Vol. 2, nr 4

136-139

EN

The exploitation of the daylight in the illumination of the of flees is one of the possibilities of the electrical energy saving for lighting. The paper presents the calculations performed in order to estimate the possible savings in Polish climate. The amount of energy consumed by artificial light sources for an exemplary office is taken as a reference. Power demands together with energy consumption for the daylight deficiencies compensation are calculated using the solar radiation measurements from September 2011 in Lodz, Poland.

20

System Zdalnego Egzaminowania

Piotrowicz M., Chudzikiewicz J.

Biuletyn Instytutu Automatyki i Robotyki

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2011

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R. 17, nr 31

37-52

PL

W artykule przedstawiono opis projektu oraz implementacji wybranych elementów Systemu Zdalnego Egzaminowania. Zaprezentowano mechanizmy obsługi bazy danych z wykorzystaniem procedur składowanych. Omówiono sposób integracji opracowywanego systemu z istniejącym systemem dziennika nauczyciela oraz sposób użytkowania aplikacji.

EN

A design description including implementation of selected elements of an examining remote system is presented in the paper. Mechanisms of database maintenance using stored procedures are shown. An integration of the elaborated system with the existing system of teacher's diary has been discussed. An explanation to the use of application is given.