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Mars Surface Exploration via Unmanned Aerial Vehicles
Published in Shashi Bhushan, Manoj Kumar, Pramod Kumar, Renjith V. Ravi, Anuj Kumar Singh, Holistic Approach to Quantum Cryptography in Cyber Security, 2023
Manjula Sharma, Akshita Gupta, Sachin Kumar Gupta
A glider is a type of aircraft without a motor. In the flight, a glider has three forces operating on it (lift, drag, and weight forces), these are exposed in each and every kind of aircraft. Although the glider has no thrust, the powered aircraft eventually has a thrust-generating engine [22].
Canard Airplanes and Biplanes
Published in James DeLaurier, Aircraft Design Concepts, 2022
From glide tests, the glider flight speed is approximately 8 ft/sec (2.44 m/sec). So, the Reynolds number for the wings is found from the equation in Imperial units given in the “Airfoils” section of Chapter 2: RN=6.28Vc¯×103=6.28×8.0×0.125×103=6280.0
Aircraft
Published in Suzanne K. Kearns, Fundamentals of International Aviation, 2018
The heavier-than-air category, however, contains a more diverse collection of aircraft. These include: Aeroplanes – engine-powered, controlled, heavier-than-air machines that derive lift from fixed wings. An aeroplane is what people most often think of when they hear aircraft. Aeroplanes are also called fixed-wing aircraft, distinguishing them from helicopters with rotating wings. Aeroplanes can be configured with wheels to land on the ground (landplanes), with floats to land on water (seaplanes,) or with a combination of floats and wheels that allows them to operate in boThenvironments (amphibians).Rotorcraft – aircraft that have rotating (rotor) blades. Rotor blades can be thought of as spinning wings, with a teardrop cross-sectional shape. When they rotate, they produce a low-pressure area above the rotors resulting in lift. Helicopters incorporate an engine that powers the rotor blades, while gyroplanes have an unpowered rotor blade along with a powered propeller.Ornithopters – aircraft that flap their wings like a bird to achieve lift. These aircraft are mostly experimental and do not play a significant role in civil aviation.Gliders – unpowered aircraft that require assistance (such as from a tow aeroplane) to become airborne. Once airborne, gliders can take advantage of air currents to maintain and even gain altitude.
Time-reversal symmetries in two-dimensional reversible partitioned cellular automata and their applications
Published in International Journal of Parallel, Emergent and Distributed Systems, 2022
Applying to , we obtain a configuration that gives the inverse process of the above. In there are a glider-44 moving to the east and a particle. Note that the pattern of the glider-44 is the same as the one at t = 43 in Figure 22. Namely, the phase of the glider-44 is shifted by the application of . These two objects interact in ESPCA-01caef, and finally produce a glider-12 moving to the south-east direction and a particle as shown in of Figure 23. Thus, a glider-44 is converted into a glider-12. Note that the pattern of the glider-12 is the one obtained by rotating the one at t = 11 in Figure 21 by 90 degrees clockwise. Namely, the phase and the direction of the glider-12 are changed by the application of .
A new method for the structural optimisation of a common type of square wing plate used in the wave glider
Published in Ships and Offshore Structures, 2019
Jian Zhao, Zhipeng Gao, Yanyan Hou, Xuewu Hong, Haiqiang Liu, Da Wang, Yilong He
As a basic part or component, the wing plate widely exists in aircrafts and underwater vehicles. Recently, the NACA (National Advisory Committee for Aeronautics) airfoil structure has been proven to be a good reference for the wave glider’s wing plate design (Ganesh Ram et al. 2014; Rocha et al. 2015; Sahin and Acir 2015). When taking the NACA airfoil as a prototype to direct the design of the wave glider’s wing plate, some fundamental geometric parameters and their functions on lift-drag performance must to be understood, such as thickness, camber, and upper, middle and lower arc surface. Singh et al. (2017) used CFD software to compare the flow behaviours and lift-drag properties of a series of NACA0012 aerofoils, and these aerofoils possess different gliding and attack angles. Furthermore, the wing plate of the underwater glider also can offer assistance for structural optimisation of wing plates in the wave glider, because it generally has a good lift-drag performance (Druecker et al. 2016; Javaid et al. 2017).
Bi-directional evolutionary topology optimization for designing a neutrally buoyant underwater glider
Published in Engineering Optimization, 2018
Tengfei Tang, Baoren Li, Xiaoyun Fu, Yi Xi, Gang Yang
The compensating volumes of the ‘Sea Eagle’ glider and the objective glider are illustrated in Figure 5. The solid line (1) is the seawater volume change from the numerical calculation method, the volume variation of the neutrally buoyant glider is equal to the total volume change of the seawater. FEA simulation is used for the glider hull compression under pressure, and the result of the ‘Sea Eagle’ glider hull volume variation is shown by the dashed line (2); the glider volume variation is linear owing to the fact that the compression of the glider hull is mainly longitudinal (Merckelbach, Smeed, and Griffiths 2009). By comparing the results of line (1) and line (2), the compensating volume of the ‘Sea Eagle’ glider is represented by the dash–dotted line (4). This means that an additional volume is required from the glider buoyancy device, which involves the consumption of energy. The volume change shown by the dash–dotted line (4) is rapidly growing in the form of curves before 300 m, and approximately linearly with depth after 300 m. As the glider volume variation is linear, it is possible that the glider hull can compensate the buoyancy after 300 m. The objective glider hull volume variation is represented by the dashed line (3); it is the structure constraint (608.8 ml at 1217 m) used in the BESO optimization procedure. The compensating volume of the objective glider is shown by the dash–dotted line (5), an approximately horizontal line is presented after 300 m and the glider hull compresses similarly to the seawater, so the glider buoyancy device does not need to compensate with additional buoyancy, something which saves on battery energy.