https://transport.vgtu.lt/index.php/Aviation/issue/feedAviation2025-02-17T18:30:36+02:00Prof. Gintautas Bureikagintautas.bureika@vilniustech.ltOpen Journal Systems<p>Aviation publishes original research, reports and reviews about aviation. <a href="https://journals.vilniustech.lt/index.php/Aviation/about">More information ...</a></p>https://transport.vgtu.lt/index.php/Aviation/article/view/23154Comparative efficiency testing of a composite hydraulic cylinder2025-02-14T18:30:34+02:00Michał Stosiakmichal.stosiak@pwr.edu.plMarek Lubeckimareklubecki@op.plMichał Banaśmichal.banas@pwr.edu.pl<p>The paper points to the increasing use of composite materials in hydraulic components. This entails many benefits, such as weight reduction which is particularly important in aviation. However, new problems arise with the use of new materials. With regard to a hydraulic actuator whose cylinder is made of a composite material, one of the issues is ensuring adequate efficiency, comparable to that of a steel cylinder. The efficiency of a hydraulic actuator is related to friction processes in the structural nodes and to leaks in the cylinder. This paper presents the original results of volumetric, hydraulic-mechanical and total efficiency tests of three designs differing in the material used as a liner of a cylinder. The materials considered as liner were CFRP composite, polyurethane F180. In addition, a steel liner was considered as a reference. Variations in actuator efficiency depending on the liner used were indicated.</p>2025-02-14T10:23:44+02:00Copyright (c) 2025 The Author(s). Published by Vilnius Gediminas Technical University.https://transport.vgtu.lt/index.php/Aviation/article/view/23126Parametric analysis of wing planforms to determine an optimal wing design2025-02-17T18:30:36+02:00Manish Kumar Chauhanmanishku.25@gmail.comMayur Zopemayurzope1777@gmail.comSrinivasa Rao Gorrepatigsrinu1882@gmail.com<p>In designing of Unmanned Aerial Vehicle (UAV), selection of an optimal wing design is a crucial part of complete UAV design process. This research explores the different aerodynamic parameters and the comparison of different wing planforms to ascertain the optimal wing design and improve the overall efficiency of an UAV. The computational analysis using XFLR5 and Open-VSP software is studied to investigate the various aerodynamic parameters of wing. The impact of aspect ratio, taper ratio, wing reference area, coefficient of lift and drag, and stall angle of attack are examined using the Analytical Hierarchy Process (AHP). The results emphasize the importance of different wing planforms and create easier selection of planform for the UAV designers. The study does not only provide the values for operating parameters but also offers practical guidance for design optimization. The semi tapered, and moderate tapered (λ = 0.5) wings are the good choice to select at the initial phase of design. The highly tapered and elliptical wings provide higher lift but are not efficient in the stalling conditions. Furthermore, the rectangular wing provides elliptical lift distribution, but it is inefficient in the lift generation.</p>2025-02-17T10:33:54+02:00Copyright (c) 2025 The Author(s). Published by Vilnius Gediminas Technical University.