Paweł Stabla

Wroclaw University of Science and Technology | WUT · Faculty of Mechanical Engineering

Composite structures, especially pressure vessels, pipelines, and additional components such as tees, reductions, or inspection openings are more and more willingly used in the chemical industry. In this research, a novel design of a low-pressure composite vessel with an inspection opening is presented. The vessels are unsymmetrical considering the...

An experimental and numerical investigation of the cylindrical carbon fiber reinforced polymer (CFRP) structures under various loads including tension/torsion loading conditions has been conducted. Various boundary conditions and parameters were taken into account to check the impact of the shear component to obtain the result. The nonlinear shear...

In this paper, preliminary studies on the failure analysis of hybrid composite materials utilizing acoustic emission and machine learning are presented. The main purpose of this study was to analyze the possibilities of using machine learning techniques as a way to better cluster the data obtained from acoustic emission. In this paper, we focus on...

Three different types (with glass, basalt and hybrid fibres) of composite rebars manufactured using the pultrusion process were loaded in four-point bending tests. All tests were carried out with acoustic emission sensors to better understand the mechanisms of damage. The data obtained were investigated using standard parameter analysis and also us...

In this paper, pultruded GFRP bars are investigated to determine their fracture properties. The double cantilever beam test (DCB) is used to assess fracture behavior under mode I loading conditions. However, due to the presence of the R-curve effect (variable fracture energy dependent on the length of the crack), it is necessary to introduce a nons...

Fibre metal laminates (FML) are a specific type of material made of both metal and fibre-reinforced composite layers. In this paper, the authors analyse the behaviour of fibre metal laminates with unusual thermoplastic matrices in composite layers under mode II loading. A three-point bending setup was used along with end notched flexural specimen (...

Fire resistance is a major issue concerning composite materials for safe operation in many industrial sectors. The design process needs to meet safety requirements for buildings and vehicles, where the use of composites has increased. There are several solutions to increasing the flame resistance of polymeric materials, based on either chemical mod...

Fibre metal laminates (FML) are a group of materials consisting of layers of both metals and fibre reinforced composites. In this paper, the authors analyse the behaviour of fibre metal laminates with unusual thermoplastic matrices in composite layers under flexural loading. A three-point bending test is used to determine the flexural behaviour and...

In this paper, the two key parameters of the filament winding technology process are investigated using both experimental and numerical approaches. While the winding angle is a commonly discussed issue, the mosaic pattern is widely disregarded. To examine its influence, nine configurations of the tubular specimens were manufactured (three winding a...

The filament winding (FW) technology is one of the emerging manufacturing practices with a high degree of excellence and automation that has revolutionized gas storage and transportation doctrine. Various pressure vessels have evolved in the last few decades, from metal to fiber-reinforced tanks, primarily for weight savings and high-pressure ratin...

The manufacturing process of composite pultruded rebars requires consideration of various aspects. In this work, the heat transfer at the pultrusion die was investigated. The aim was to analyze the heat transfer from the die to the GFRP composite rebar. The 3D numerical model was prepared to simulate the pulling process of the rebar through the hea...

This paper presents the numerical simulation of the GFRP rebars subjected to the bending loading. Additionally, the comparison of the mechanical properties of CFRP/GFRP laminates with different fiber volumes is given according to the widely used hypotheses available in the literature. The most suitable hypotheses are the Abolish regarding Kirchhoff...

The problem with composite rebars in the civil engineering industry is often described as the material’s brittleness while overloaded. To overcome this drawback, researchers pay attention to the pseudo-ductility effect. The paper presents four-point bending tests of pure unidirectional (UD) rods with additional composite layers obtained by filament...

Although cooling at ambient temperature is widely used and is said to be safe and convenient, faster cooling may have an influence not only on the time of the manufacturing process but also on the mechanical response, especially the residual stress. The study aimed to investigate the influence of the cooling rate after curing on the mechanical resp...

This paper is focused on radial-compression of filament-wound composite pipes. An important but frequently disregarded is the issue of the choice of the winding pattern. The influence of the pattern on the strength of pipes is the subject of the investigation. Since the real geometry of filament-wound tubes is complicated researchers use simplified...

Purpose Engineered stone is a material which can be described as an artificial stone. The exemplary application area is sink production. There are very few research projects about this type of material. In fact, most of them are research conducted by the manufacturing company, which are limited to the basic properties of the material. However, know...

In this work, different approaches to fibre-metal laminates modelling are presented. Micromechanical, mesomechanical and macromechanical models are discussed. The application of these approaches for exemplary fibre-metal laminate made of aluminium and epoxy resin/glass fibre layers are shown. The classical laminate theory was used to obtain enginee...

In this paper a comparison of two motorcycle subframes made of different composite material layups is presented. The first sample is manufactures purely from the carbon and carbon-aramid wovens. The second sample contains additionally a foam core. The elements were tested on a strength machine in order to obtain the curve of force-displacement. Esp...

W artykule tym przedstawiono proces projektowy oraz konstrukcyjny form do laminowania. W celu stworzenia takich form wykorzystano technologię druku 3D. Artykuł przedstawia dobór nie-zbędnych parametrów, metodykę dzielenia oraz łączenia poszczególnych elementów, a także efekt w postaci gotowych form.

W artykule przedstawiono wynik optymalizacji topologicznej elementu ramy motocyklowej Lekkiego Elektrycznego Motocykla LEM Falcon. Analiza przeprowadzona metodą elementów skończonych przyniosła pozytywne rezultaty w postaci nowej geometrii blachy zastrzałowej. Otrzymany element posiada mniejszą masę, niż geometria bazowa bez przekraczania naprężeń...

This article describes design problems of a small CNC milling machine which is build/being built building by students from the Association of Mobile Robots and Vehicles affiliated with Wroclaw University of Technology. The paper describes the process of designing the device and includes the FEM analysis which helps with constructing the components...

The article presents the idea of creating a shock arm for the Light Electric Motorcycle-LEM Thunder. Nowadays, linkage systems used in motorcycles do not offer various transmission force ratios. The only way to change forces in the rear suspension in motorcycles consists of changing the parameters of a damper-stiffness, damping factor or preload. T...

The aim of the work was to present a project of the composite motorcycle's subframe made of composite material. The current knowledge about this element concentrates mostly on the technology of the injection moulding of plastics. Therefore, fibre reinforced plastic composites were investigated. Firstly, a strength pre-analysis using FEM method was...

As part of the work, the possibilities of scientific cooperation between the Military Institute of Technical Engineering and the Wrocław University of Science Technology in the field of design, manufacture and testing of lightweight constructions were analysed. In the assumptions of cooperation, the key construction material is a polymer composite...

This article presents design and construction of the light brake bracket for a Light Electric Motorcycle – LEM Falcon. Article presents project assumptions – choice of the material, technologic process and shows the typical load calculations. At the end of the article there are presented the FEM analysis of the bracket. The results between the mate...

This article presents analysis of the experimental results of motorcycle's subframe made of fiber reinforced plastic composites. As a reinforcement we used carbon and aramid fibers. The matrix was an epoxy resin. The aim of analysis was to check the results of the FEM calculation. The first four layer of composites was manufactured by a vacuum infu...

This article presents the construction and modularity of welding equipment. The product was used for simplifying the process of motorcycle's frame welding for two electric motorcycles: LEM Bullet and LEM Falcon. The paper contains the welding equipment's main assumptions and subsequent amendments. The economical aspect was also taken into considera...

This article presents the FEM analysis of motorcycle's subframe made of fibre reinforced plastic composite (FRP). As a reinforcement carbon and aramid fibres were investigated. The matrix was an epoxy resin. The aim of the analysis was to obtain the optimal laminate structure. The potential composite would be manufactured by a vacuum infusion proce...

The main goal for this article is to describe reasons and whole creating process of the linkagesystem in LEM Bullet. LEM Bullet is the first motorcycle made by members of Scientific Association of Mobile Robots and Vehicles that has its rear suspension equipped with the linkagesystem. The main attention was paid for the optimization of the geometry...