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Flow Visualization Over an Airfoil with Flight Control Surfaces in a Water Tunnel

Abstract

This paper demonstrates the feasibility of using-a water tunnel for the visualisation of flow in airfoils with flight control systems in the form of slots and flaps. Furthermore, the issue of using water tunnels for scientific and training purposes was explained. The technology of 3D printed models for practical tests in a water tunnel was also presented. The experiment included conducting flow visualisation tests for three airfoil models: with the Clark Y 11.7% as the base airfoil and the same airfoil with a slot and a flap. Moreover, a modification to dye injection system was introduced. The presented results of flow visualisation around models with the use of dye, confirmed the effectiveness of the applied methodology. The results and conclusions may be utilized to verify most flow-related issues in hydrodynamic tunnels and can also be used as a training element.

Open access
Importance of Personal Data Protection Law for Commercial Air Transport

Abstract

In the review below the author presents a general overview of the selected contemporary legal issues related to the present growth of the aviation industry and the development of aviation technologies. The review is focused on the questions at the intersection of aviation law and personal data protection law. Massive processing of passenger data (Passenger Name Record, PNR) in IT systems is a daily activity for the contemporary aviation industry. Simultaneously, since the mid- 1990s we can observe the rapid growth of personal data protection law as a very new branch of the law. The importance of this new branch of the law for the aviation industry is however still questionable and unclear. This article includes the summary of the author’s own research conducted between 2011 and 2017, in particular his audits in LOT Polish Airlines (June 2011-April 2013) and Lublin Airport (July - September 2013) and the author’s analyses of public information shared by International Civil Aviation Organization (ICAO), International Air Transport Association (IATA), Association of European Airlines (AEA), Civil Aviation Authority (ULC) and (GIODO). The purpose of the author’s research was to determine the applicability of the implementation of technical and organizational measures established by personal data protection law in aviation industry entities.

Open access
The Influence of the Fastener Hole Preparation Method on the Fastener Pull-Through Process in a Carbon Composite

Abstract

This article studies the pull-through resistance of a titanium carbon fibre-epoxy resin laminate fastener. Coupons with fastener holes made with different methods were compared – drilled, milled on a CNC plotter and special fibre application during laminate production. The tests were conducted according to the ASTM D7332 test standard. The studies showed that the fastener hole preparation method impacts the laminate’s resistance to fastener pull-through. Coupons with holes made with standard (drilling and milling) methods showed fastener pull-through resistance higher, on average, by 6.5% than in coupons with holes placed during plate production. Fastener work to rupture was also higher for coupons with milled and drilled holes. Microscopic observations in UV-light, using a fluorescent penetrant, showed differences in failure mechanisms between individual coupons, especially the lack of fibres in the 0° direction, in immediate vicinity to a hole prepared during laminate application.

Open access
The Life Cycle of a Training Project in a Research and Development Unit

Abstract

The article describes the life cycle of a training project in a research and development unit, from setting the training target, through analyzing the needs of the group, establishing workshops’ programs and logistics, up to the evaluation and implementation support. The role of human capital has been presented in the article, thus the need for training organization has been demonstrated to improve quality of work. The article also describes characteristics of the training market, defining types of projects addressed to representatives of the most often trained groups in the research and development unit, like professionals, managers and research workers. Methods and tools aiding the training system analysis and monitoring have also been introduced in the text with a goal to reflect customer, employer, and trainee satisfaction. A process of raising qualifications of employees was described at the Institute of Aviation. It has been found that internal trainings from the subject matter of “project management” are the best solution for research and development centers.

Open access
Mechanical Properties of the Package of Ferromagnetic Sheets

Abstract

The paper presents the measurement method and results as well as the results of comparative calculations aimed at determination of material data for the package of ferromagnetic sheets insulated with epoxy lacquer. During the test, the package of sheets was treated as a 3D orthotropic material. The values of Young’s and Kirchhoff’s moduli for a pre-compressed package of sheets, in accordance with the used manufacturing technology of the medium and high power electric motors’ rotors, were detennined. The carried out FEM comparative calculations confirmed that the determined mechanical parameters of the package of sheets as a 3D orthotropic material, i.e. Young’s and Kirchhoff’s moduli, for the compressive stress range of 1.0÷2.5 MPa, are included in the linear range. It was assumed that the determined mechanical properties of the package of sheets are necessary at the design stage for FEM simulation calculations of the electric motors’ vibration and strength properties. As a result of the tests, it was found that they should be repeated in order to determine the properties of other sheets or those coated with different insulating lacquer.

Open access
Process of Preparing and Laying Carbon Prepregs

Abstract

This article contains information on the technological process involved in the production of a composite structure with carbon-epoxy prepregs including critical parameters of the process. The information in the publication shows respectively:

1. Using composite components for constructing the airframe,

2. ways of storing and preserving carbon prepregs on a matrix of thermosetting resins,

3. specific types of varying weave fabrics used in the prepregs,

4. way of preparing material for the process,

5. cutting tools,

6. preparing swage,

7. list of the most popular materials, their characteristics, pros and cons of their applications,

8. issues related to types of release agent,

9. parameters of selecting release agents in the process of manufacturing structures with carbon prepregs,

10. process of laying plies in a layered structure,

11. defects which result from improper material laying in swage,

12. preparing the structure for heating and technical parameters of the process.

Open access
Quality Control Process of Manufactured Composite Structures

Abstract

The paper includes a description of the composite material used in the aviation industry. It presents the technological development of composites in terms of their use in the most important elements of the aircraft structures, such as a spar and aircraft wing sheathing, which are subjected to high loads during operation. The type of the material implemented for production was listed and the most commonly occurred incompatibilities during the carbon pre-impregnate manufacture and transport were described.

The manufacture diagram of composite elements with a polymer matrix was presented and the quality control system carried out at each mentioned stage (material storage, defrosting, cutting of dies, structure forming, polymerisation) was discussed.

The methods of non-destructive tests of carbon laminates in a polymer matrix were also listed, describing the most effective of them, i.e. a method of ultrasonic tests.

The conclusions were drawn and the development possibilities of ultrasonic tests both in terms of quality improvement and reduction of time for detecting incompatibilities in composite structures were described.

Open access
Research of Dependence of the Damage Area on Tow Width on Filament-Wound Composite Tubes

Abstract

This paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible.

Open access
Tests of Damage to Inconel 718 Alloy Used in Aviation

Abstract

Inconel 718 alloy was tested. A new type of specimens of variable cross-sectional area measuring part was used for the tests. This provided a continuous distribution of plastic strain in that part of the sample. The proposed method enables to replace a series of specimens by one specimen. The degradation of the material was obtained by static tensile test and the creep test. The permanent deformation that varies along the specimen axis allows for an analysis of damage induced by a plastic deformation. The degradation of the alloy corresponds with the changes of acoustics properties of the material - attenuation of ultrasonic waves. It allows to detennine the degree of damage to the material using a non-invasive - ultrasonic method. Using the damage parameter proposed by Johnson allows to obtain correlation between the non-destructive results and a damage degree of the material. The presented testing method delivers information about changes in the material structure caused by permanent deformation.

Open access
Improved Prioritization Criteria for Road Infrastructure Projects

Abstract

This report’s main aim is to propose a methodology for assessing state-budget-funded projects based on a rigorous selection model, including clear and effective prioritization criteria. This report first argues that project prioritization and selection should be optimized against four dimensions: absorption, impact, legitimacy, and capacity. Second, it provides a diagnostic of the National Program for Local Development (PNDL), managed by the Ministry of Regional Development and Public Administration (MRDPA), as the most significant source of state-budget funding for local infrastructure projects. The PNDL’s current design and implementation leaves room for improvement, as reflected by the lack of strategic direction in allocating funds and the continued rise in the number of projects that get started without a feasible timeline for their completion. Further, this report makes recommendations for improvement of project evaluation and selection procedures for local infrastructure development projects, with a special focus on prioritization criteria and viable funding sources for each type of investment. The practical purpose is to enhance the efficiency and effectiveness of proposed investments, maximizing impact in the context of inherently limited available financial resources. A complementary focus is on opportunities for harmonizing and better coordinating investments across various sources of funding, in the context of nearly EUR 40 billion available to Romania from the EU for the 2014-2020 programming period.

Open access