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1

Piany luminescencyjne – opracowanie technologii autorskiej

Majsiak Lena, Mazurczyk Wiktoria

Szkło i Ceramika

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2025

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R. 76, nr 3

47--55

PL

Opisana technologia pian luminescencyjnych jest wynikiem połączenia dwóch indywidualnie opracowanych technologii. Autorskie szkliwa luminescencyjne umożliwiają wytwarzanie obiektów ceramicznych stosowanych jako alternatywne źródło światła, zaś piany ceramiczne to materiały o właściwościach dźwiękochłonnych, podlegające wielokrotnemu recyklingowi. Wykonanie wspólnego tworzywa podyktowane było celem uzyskania kombinacji właściwości obu tych autorskich materiałów i poszerzenia tym samym obszaru badań i możliwości przyszłych zastosowań. Niniejszy artykuł przybliża specyfikę zagadnień związanych z luminescencją i pianami ceramicznymi oraz opisuje wspólnie opracowaną technologię i towarzyszącą jej drogę badawczą.

EN

The described luminescent foam technology is the result of combining two individually developed technologies. Luminescent glazes enable the production of ceramic objects used as an alternative light source, while ceramic foams are materials with sound-absorbing properties that can be recycled multiple times. The realization of a joint material was motivated by the goal of combining the properties of both original materials and thus expanding the area of research and possibilities for future applications. This article introduces the specifics of issues related to luminescence and ceramic foams and describes the collaboratively developed technology and the accompanying research path.

2

Dynamics response analysis and mechanical experimental investigation of a double-span multi-support shaft system in micro gas turbines

Lin Hao, Song Leiming, Geng Haipeng, Feng Sheng, Li Ling

Journal of Theoretical and Applied Mechanics

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2025

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Vol. 63 nr 1

115--129

EN

This study delves into analysis of dynamics and experimentation concerning a double-span multi-support shaft system in micro gas turbines. Critical speed analysis was conducted, accompanied by numerical solutions providing insights into the natural frequency. Additionally, an unbalanced response and vibration amplitude of the shaft were calculated, serving as crucial inputs for dynamic balancing considerations. The study also examined the influence of stiffness coefficient variations in bearings on the unbalance response. Dynamic balancing experiments of the motor rotor and the compressor-turbine rotor were conducted separately. Then a vibration experiment for the double-span multi-support shaft was executed at an experimental speed of 60000 r/min. The research revealed that rotors could be regarded as rigid bodies throughout the operational speed range. This study holds significant engineering implications and a practical application value.

3

Design and experiment of membrane-type acoustic metamaterials used in EMUs to control low frequency noise

Liu Peng, Lin Hao, Gao Pan, Tian Pengyi, Jiang Chengcheng, Song Leiming, Dong Xiaoqing

Journal of Theoretical and Applied Mechanics

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2025

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Vol. 63 nr 2

279--287

EN

Acoustic metamaterials, a new type of material with great design flexibility, have been widely studied by scholars in recent decades. For high-speed electric multiple units (EMUs), a membranetype acoustic metamaterial is used to design a lightweight sound insulation material that adapts to the space requirements within the low frequency range. A theoretical analysis on the membrane-type acoustic metamaterial was carried out. The sound insulation coefficient was calculated. Experimental comparisons were conducted on six different thicknesses of films combined with five types of additional masses. The experimental results verified the sound insulation performance. It has great potential for designing lightweight noise reduction structures.

4

Formation of concavities on the ends of parts manufactured on CNC skew rolling mills

Pater Zbigniew, Bulzak Tomasz, Tomczak Janusz, Shu Xuedao, Xia Yingxiang

Archives of Civil and Mechanical Engineering

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2025

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Vol. 25, no. 1

art. no. e8, 2025

EN

This study investigates the problem of concavity formation on the ends of parts manufactured on CNC skew rolling mills. Numerical modeling and Taguchi method were used to determine the effects of the main parameters of skew rolling (i.e., forming angle, skew angle, reduction ratio, temperature, steel grade, dimeter ratio, velocity ratio) on the depth of concavities formed on the product ends. The simulations showed that the only parameter to have a significant impact on the concavity depth was the reduction ratio. The FEM results were then used to establish equations for calculating concavity depth and allowance for excess material with concavity. For more universality, the established equations took into account the billet diameter. The experimental validation showed high agreement between the numerical and the experimental concavity depths.

5

Experimental aeroacoustic studies of selected three types of helicoidal resonators

Łapka Wojciech, Jakubowski Piotr

Vibrations in Physical Systems

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2024

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Vol. 35, nr 1

art. no. 2024102

EN

The paper presents experimental studies of selected three types of helicoidal resonators carried out on an aeroacoustic laboratory stand with the use of pink noise and a duct terminated with a reverberation chamber. The same ratio s/d = 1.976 is considered for three numbers of helicoidal turns n = 0.671, n = 0.695 and n = 1.0. The results of the acoustic attenuation performance depending on the air flow velocity were compared in relation to the numerical tests carried out, which resulted in a decrease in resonance frequencies with an increase in the air flow velocity. The measurements were carried out with a high resolution of the FFT spectrum in order to illustrate the changes in the acoustic attenuation performance as accurately as possible. One-third octave bands of flow noise studies were also carried out.

6

CFD Simulation of Heat Transfer Through a Window Frame

Basok Borys, Novikov Volodymyr, Pavlenko Anatoliy, Davydenko Borys, Koshlak Hanna, Goncharuk Svitlana, Lysenko Oksana

Rocznik Ochrona Środowiska

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2024

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Tom 26

56--64

EN

The use of various coatings with a low level of radiation on the glass elements of window structures, filling the interglacial space in double-glazed windows with inert gases instead of air, increasing the number of cameras in double-glazed windows, other constructive measures aimed at improving the thermal insulation properties of double-glazed windows, led to a significant increase in the thermal resistance of the fenestration system. However, little has changed in the design and construction of window frames and edge areas adjacent to building facades, leaving these elements responsible for heat transfer through modern windows. In this article, with the help of three-dimensional CFD modeling, the thermal insulation properties of window frames are investigated in the most complete setting, taking into account the effect on heat transfer through the profile of the window frame of the adjacent walls of the building facade on one side and the double-glazed unit on the other. Finding out the thermal insulation parameters of the window frame will help to make appropriate changes in its design.

7

Krajowe laboratorium sieci i usług PL 5G: kierunki badań i perspektywy rozwoju techniki 5G/6G

Bęben Andrzej, Sosnowski Maciej, Jóźwiak Witold, Woźniak Józef, Gierłowski Krzysztof, Hoeft Michał, Natkaniec Marek, Boryło Piotr, Belter Bartosz, Furmann Maksymilian, Schauer Patryk, Falas Ł., Wawrzyński A., Michalski Igor, Więcek Dariusz

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2024

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nr 4

33--42

PL

Artykuł przedstawia unikatową infrastrukturę badawczą PL 5G opracowaną w ramach projektu „Krajowe laboratorium sieci i usług 5G wraz z otoczeniem” oraz kierunki badań dotyczących techniki 5G oraz przyszłej sieci 6G. Laboratorium umożliwia prowadzenie praktycznych eksperymentów, w środowisku zbliżonym do warunków sieci operatorskiej, dotyczących rozwoju techniki 5G/6G, a także szerokiego spektrum jej zastosowań w środowiskach terenowych, tj. morskim, lotniczym, przemysłowym czy miejskim. Przedstawiono również przykładowe eksperymenty wykorzystujące rozważaną infrastrukturę.

EN

The article presents the unique infrastructure of the National Laboratory for Advanced 5G Research (PL 5G) and the research directions for beyond 5G and future 6G systems. The laboratory enables practical experiments in an environment similar to the operator's network regarding the development of 5G/6G technology and a wide range of its applications in maritime, aviation, industrial, and urban environments. We also present some exemplary experiments to illustrate infrastructure capabilities.

8

Experimental study of a puncture warning system for a jack-up offshore platform

Liu Zailiang, Li Xiaobin, Song Yuelin, Xie Yonghe, Li Detang

Polish Maritime Research

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2024

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nr 3

61--70

EN

During the operation of jack-up offshore platforms, the complex and variable seabed geological conditions involved can lead to serious accidents, such as pile leg punctures and platform tilt. The aim of this study is to introduce an early warning method for punctures that ensures the operational safety of these platforms. To accomplish this, a real-time monitoring and controlling system is designed using a programmable logic controller that shares data from sensors measuring displacement, tilt, and pressure. In addition, an experimental device is constructed to simulate a jack-up offshore platform in order to assess the safety response of the control system. The working state of the platform under different working conditions (puncture of one independent pile, same side or diagonal piles, and three-pile linkage) is evaluated by analysing the structural motion response, including platform tilt and foundation pressure. The findings reveal that the system developed in this study accurately detects the tilt condition of the offshore platform, and can ensure the operational safety of jack-up offshore platforms.

9

Validation research of pressure decay test method for internal leakage detection of hydraulic cylinder

Li Weijie, Qian Xinbo, Chen Xinyuan, Li Feihong, Lu Yan

Eksploatacja i Niezawodność

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2024

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Vol. 26, no. 2

art. no. 184039

EN

Leakage test is one of the acceptance tests to ensure hydraulic cylinder reliability. Under the consideration of economic and technical maturity conditions, the existing internal leakage detection methods may be difficult to achieve rapid screening. After research, the pressure decay test method is a common method of quickly testing hydraulic cylinders for internal leakage in the manufacturing industry. However, the validity of the pressure decay test method has not been theoretically verified, limiting the versatility of the method. This paper will theoretically validate the effectiveness of the pressure decay test method and provide important theoretical support for its use as a general rapid screening method for internal leakage, thereby improving the reliability and safety of hydraulic systems. Both simulation and experimental results show that there is a linear relationship between the pressure decay rate and the internal leakage rate. Especially for working pressures greater than 16 MPa, the pressure factor has an insignificant impact on the application of this method.

10

Methane emission measurements along underground galleries of coal mine

Ostrogórski Piotr, Skotniczny Przemysław

Archives of Mining Sciences

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2024

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Vol. 69, no. 1

107--114

EN

The article shows the results of research on methane concentration changes along mine galleries. The experiment was conducted in a longwall area mined using a U-type system, and the results were obtained in situ. The main goal was to measure methane concentration by function of gallery length and dividing segments of methane data into segments, which ultimately enabled separate analysis of these methane data. The analysis led to the diagnosis of methane hazard through the detection of exceedance of the assumed tolerance area.

11

Methane concentration measurements in the longwall area as a data source for the assessment of methane hazard

Dziurzyński Wacław, Ostrogórski Piotr, Skotniczny Przemysław

Archives of Mining Sciences

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2024

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Vol. 69, no. 4

675--684

EN

This article discusses the challenges of coal mine safety, particularly methane hazards, in the context of decreasing workforce and the need for more autonomous solutions. As hard coal production faces a phase-out due to international energy policies, the mining industry struggles with retaining skilled workers. The Sectional Methane Hazard Detection System (SDZM ) is proposed as an autonomous solution to detect methane hazards by measuring methane concentrations along underground workings. The system operates using a series of algorithms that analyze the concentration data and identify hazard zones without the need for highly qualified personnel. The SDZM method involves collecting methane concentration data from different sections of the mining operation and comparing them to reference profiles to assess potential hazards. A study conducted in the 841A longwall area of KWK B mine used simulations to assess methane distribution, which was then used to test the SDZM system’s algorithms. The results show that the system can accurately detect high methane hazard levels, with sensitivity varying depending on the parameters set, such as the tolerance field for methane concentration changes. The study concluded that the SDZM system is effective in detecting methane hazards, requiring minimal additional skills from workers. The system’s performance can be enhanced by adjusting parameters like the methane concentration tolerance field, though excessively narrow tolerances could lead to false positives. Overall, the SDZM provides a valuable tool for enhancing safety in mines by autonomously identifying high-risk areas related to methane emissions.

12

Study on failure modes and calculation method of the cast steel joint with branches in treelike structure

Chen Feng, Sun Yun, Sun Shuxuan, Song Da, Liu Yangbing

Archives of Civil Engineering

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2024

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Vol. 70, nr 1

589--604

EN

The treelike structure links members and transfers loads via its solitary cast steel joint with branches. Therefore, the joint’s bearing capacity significantly affects the treelike structure’s stability, security, and economics. This paper utilized experimental verification and numerical modeling to examine the mechanical behavior of cast-steel joints with branches in the treelike structure under various loading conditions. Then, researchers investigated the failure process and mechanism of joints, and the three most common failure modes were outlined. Furthermore, the researchers proposed the bearing capacity calculation formula based on the common failure modes. The results show that the three common failure modes of the cast-steel joints with branches under different loading conditions are the failure in the joint core area under the axial load, the failure in the main pipe compression side under eccentric load, and the failure in the compression side of the single branch pipe root when the single branch pipe is under the uneven load. The suggested empirical calculation method can serve as a reference point for similar engineering practices design.

13

Numerical Modelling of a Rotary Compression Test on a Cylindrical Specimen

Pater Zbigniew

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 4

23--32

EN

This paper reviews studies on the modelling of the Mannesmann effect, which leads to the formation of an axial crack in parts formed by cross and skew rolling. This effect also occurs in the rotational compression (RC) test of a cylindrical specimen, which is used to determine the critical damage value. RC tests were carried out under laboratory conditions at the Lublin University of Technology on C45 steel specimens formed at 950°C. Based on the tests, the crack propagation was presented as a function of the progress of rotational compression, measured by the length of the deformation path. The RC tests were numerically modelled in Forge® using four ductile fracture criteria. The effectiveness of the Mannesmann effect modelling was evaluated by comparing the numerically predicted cracks with the experimentally determined ones. In addition, the influence of an occurring axial crack on the stress state in the forming specimen was analysed.

14

Forging of a Hollow Ball Using a Deformable Insert Assembly

Samołyk Grzegorz

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 5

32--40

EN

The paper presents selected results of numerical analysis and experimental verification. The subject is the analysis of cold forging of a thin-walled hollow ball. The process of making a ball out of aluminum alloy and steel is considered. A distinctive feature of this process is the use of a special deformable insert assembly. It consists of two shaped expanding tubes, a distance ring and a centering tube. Each of these elements has a specific function, which is characterized in this article. FEA simulation allowed proving the functionality of the insert assembly and comparing the cold forging of a steel and aluminum part, using the same inserts. Attention was also focused on the impact of the accuracy of the positioning of the insert assembly. Experimental verification confirmed the correctness of the modeling and complemented the results from FEA analysis.

15

Experimental-Numerical Analysis of Thin-Walled Box Structures Stiffened with Corrugated Ribs, Subjected to Torsion

Kopecki Tomasz, Mazurek Przemysław

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 5

287--297

EN

The study presented the results of model experimental investigations on box structures made using additive manufacturing. The examined models had walls with reinforcements in the form of corrugations. An experiment was also conducted using a reference model without stiffeners. The aim of the study was to determine the influence of corrugation geometry on the shape and magnitude of structure deformations, as well as on the level of critical loads. The experiments were conducted using a dedicated research stand. Nonlinear numerical analyses of selected structure variations were also carried out using finite element method-based software.

16

Zależność wartości współczynnika przepływu C od grubości kryzy z wlotem stożkowym

Golijanek-Jędrzejczyk Anna

Przegląd Elektrotechniczny

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2023

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R. 99, nr 11

20--25

PL

W artykule przedstawiono wyniki badań numerycznych i eksperymentalnych pięciu kryz z wlotem stożkowym o współczynniku przewężenia  równym 0,24, o grubości od 2,5 mm do 31 mm (każda ścięta skośnie pod kątem 45°) umieszczonych w wodnej instalacji hydraulicznej przy przepływach laminarnych i turbulentnych. Uzyskane rezultaty potwierdziły, że wraz ze wzrostem grubości (w badanym zakresie liczb Reynoldsa od 1690 do 14430) tego typu kryzy wartość współczynnika C dąży do wartości 0,9.

EN

This paper presents the results of a numerical and experimental study of five conical inlet orifices with a reduction ratio  equal to 0.24, with thicknesses ranging from 2.5 mm to 31 mm (each bevelled at 45°) placed in a hydraulic system with water medium in laminar and developed turbulent flows. The results confirmed that as the thickness increases (in the range of Reynolds numbers studied, from 1690 to 14430) of this type of orifice, the value of the C -factor tends to be 0.9.

17

Preservatives in fruit jams

Żmuda-Czerwonka Wioletta

Polish Technical Review

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2023

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No. 1

18--20

EN

The modern human diet is the subject of research and interest for a large group of specialists. The unlimited capabilities of synthesising new chemical substances and the far-reaching changes in legislation create a space for expanding the list of permissible food additives. Despite the research conducted on new substances, the consumers are afraid that not all additives are sufficiently safe. This is frequently due to lack of access to objective and scientifically-verified information. The most concern is caused by the use of multiple additives in the same food product, which increases the risk of their accumulation in the human body. The objective of this paper is to discuss preservatives added to jams. It involves a discussion of the technological process and indicates the moment that a given preservative is added, showing photographs and findings from an experiment conducted on a single type of jam. The experiment was conducted under domestic conditions.

PL

Dieta współczesnego człowieka to przedmiot badań i zainteresowania dużej grupy specjalistów. Nieograniczone możliwości syntezy nowych substancji chemicznych i daleko idące zmiany w ustawodawstwie dają pole do rozszerzania listy dopuszczalnych dodatków do żywności. Pomimo badań nad nowymi substancjami istnieje obawa konsumencka, że nie wszystkie dodatki do żywności są wystarczająco bezpieczne. Jest to często wynikiem braku obiektywnych i potwierdzonych naukowo informacji. Najwięcej obaw budzi stosowanie wielu dodatków w jednym produkcie spożywczym, a to zwiększa ryzyko ich kumulacji w organizmie człowieka. Założeniem artykułu jest przybliżenie jakie substancje konserwujące pojawiają się w dżemach. Przedstawienie procesu technologicznego i wskazanie momentu kiedy dana substancja konserwująca jest dodawana oraz przedstawienie zdjęć i wniosków z doświadczenia jakiemu poddano jeden rodzaj dżemu. Doświadczenie to wykonano w warunkach domowych.

18

Study on the influence of chamfer perforation on heave and pitch of a single floating platform

Wang Wei, Fan Sheming, You Yunxiang, Zhao Cheng, Xu Liqun, Wang Guibiao, Lu Zhiqiang

Polish Maritime Research

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2023

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nr 1

43--53

EN

The aim of this work is to study the influence of chamfered perforation and chamfering on the heave and pitch motion of a single floating wind power platform with an anti-heave device. Firstly, the hydrodynamic performance of a single floating body with different chamfers, or without perforation, is calculated and analysed. Secondly, the motion of a model without perforation and with 35° chamfered perforation is captured and studied in a towing tank. The results show that when the wave height is large and the period is small, the perforated device has a certain effect. When the wave height and period are small, the pitch suppression effect of chamfered perforation is more obvious than that of non-chamfered perforation. When the period and wave height are large, the heave suppression effect of non-chamfered perforation is better than that of chamfered perforation. In experimental research, the perforated floating body has a certain effect on restraining the heave and pitch of a floating body under most working conditions, and the effect of restraining the pitch is obviously better than that of restraining the heave.

19

Identification of the object motion trajectory in a digital image using the Kalman filter

Piątkowski Tomasz

Journal of Automation, Electronics and Electrical Engineering

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2023

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Vol. 5, No. 3

31--45

EN

The paper concerns identification of the object motion trajectories in a digital image. An image analysis procedure was used consisting of two methods: BLOB identification and Kalman filter. BLOB identification is the superior method, and the Kalman filter is an alternative one, used to determine the motion trajectories only in the event of incorrect BLOB identification. Data from the correct BLOB identification are used on an ongoing basis in the process of training the Kalman filter. In this way, the filter becomes a model of a physical object that allows predicting the future state based on the object's current behaviour. The use of two complementary image analysis methods allows to determine the motion trajectories of the object's characteristic points in conditions of uneven scene lighting. The effectiveness of the method was confirmed in experimental rests.

20

Experimental identification of the force and moment characteristic of symmetrically and non-symmetrically profiled annular seals

Kuhr Maximilian M. G., Pelz Peter F.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 6

art. no. e147062

EN

In modern turbomachinery, the performance and reliability is often limited by shaft vibrations induced by fluid film forces and moments of (i) plain or (ii) profiled annular seals. Therefore, these narrow annuli are mainly responsible for the overall system behaviour, i.e. safe operation and maintenance intervals. However, many studies focus only on the characteristics from the forces due to the translational motion, although the influence of the rotordynamic tilt and moment coefficients is well known. Therefore, these additional coefficients are much less researched. Especially, for profiled seals, the availability of reliable experimental data for validation purpose is rare. To overcome this fact, a test rig is operated at the Chair of Fluid Systems at the Technische Universität Darmstadt. The generic experiments presented here investigate the force and moment characteristic of plain, symmetrically profiled and non-symmetrically profiled annular seals within the relevant parameter range for turbulent flows in pumps. The investigations focus on the influence of the annulus length as well as the pressure difference across the annulus.