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Design, Testing, and Realisation of a Medium Size Aerostat Envelope

A. Kumar, S.C. Sati, A.K. Ghosh
2016 Defence Science Journal  
The aerostat envelope is the aerodynamically shaped fabric enclosure part of the aerostat which generally uses helium for lifting useful payloads to a specified height.  ...  Equilibrium studies are then explained for balancing forces and moments in static conditions. The tether profile estimation technique is discussed to estimate blow by distance and tether length.  ...  The methods for carrying out equilibrium analysis, tether tension and tether profile estimation have been presented for the given configuration. important design parameters were estimated for the entire  ... 
doi:10.14429/dsj.66.9291 fatcat:7tgkjwpz2fe65h62xzah34ym7u

Stability Analysis of a Tethered Aerostat

Casey Lambert, Meyer Nahon
2003 Journal of Aircraft  
The added mass coefficients k; and k3 were estimated using data for ellipsoids.!  ...  Aerodynamic Parameters The aerodynamic parameters used in the dynamics model must be estimated for this particular aerostat.  ... 
doi:10.2514/2.3149 fatcat:2ai4fmgl25ao7cg3cqyrvviksa

Influence of Ballonet Motions on the Longitudinal Stability of Tethered Aerostats

James DeLaurier
1980 Journal of Aircraft  
5x, from Eq. (26) = aerodynamic angle of attack, w/U, = perturbed cable angle = cable angle defined in Fig. 4 = complex eigenvector term for 7 from Eq. (26) = quantity perturbed from equilibrium = quantity  ...  The volume is organized to provide a detailed coverage of both the available experimental data and the theoretical prediction methods in current use.  ... 
doi:10.2514/3.57906 fatcat:2cn7u2uii5emxmbjgnzckk7juu

Cable Control of an Aerostat Platform: Experimental Results and Model Validation

Casey Lambert, Meyer Nahon, Dean Chalmers, Gabriele Gilardi
2007 Journal of Guidance Control and Dynamics  
The method for varying the length of the cable using a lumped-mass model is similar to a technique developed for simulating marine cables in reel-in/payout operation [14].  ...  A., “A Method for Holding a Pilot Balloon or Light Aerostat at a Predetermined Height for Meteorological Observations,” Meteorologiya i Gidrologiya, No. 4, 1978, pp. 102-104.  ... 
doi:10.2514/1.22598 fatcat:cubossjv5za3hfucvmtkamqyym

Dynamic Response to Turbulence of Tethered Lighter-Than-Air Platforms

S. Redi, G. S. Aglietti, A. R. Tatnall, T. Markvart
2011 Journal of Aircraft  
The input parameters considered in the method are derived from experimental and simulated data, which are elaborated to obtain the static and dynamic atmospheric properties in terms of mean windspeed profile  ...  The results, even though they are obtained for a specific example application, demonstrate the general viability of the algorithm proposed for the evaluation of the dynamic response of high-altitude tethered  ...  acknowledge the support of the Mesosphere-Stratosphere-Troposphere Radar Facility at Aberystwyth, funded by the United Kingdom Natural Environment Research Council and the British Atmospheric Data Centre, for  ... 
doi:10.2514/1.c031137 fatcat:t4umbdqrlfaczdjz5gth4r63vm

Tethered Aerostat Modeling Using an Efficient Recursive Rigid-Body Dynamics Approach

Brad Hembree, Nathan Slegers
2011 Journal of Aircraft  
Simulations are used to show how the proposed recursive model can be used to investigate the dynamic response and tether loads for a 17 m tethered aerostat in response to varying winds.  ...  A tethered aerostat model is developed using a computationally efficient recursive tether model.  ...  Li and Nahon [2] proposed a modeling and estimation method for airships, then performed analysis based on a linearized version of the model and flight data.  ... 
doi:10.2514/1.c031179 fatcat:r4vniypuvfdafe6vtsxrrjlh5u

Dynamics of Circularly Towed Aerial Cable Systems, Part I: Optimal Configurations and Their Stability

Paul Williams, Pavel Trivailo
2007 Journal of Guidance Control and Dynamics  
However, the method can be used with any aircraft parameters, which should prove useful for more detailed design for specific aircraft configurations.  ...  Equilibrium Configurations Equilibrium solutions for the towed-cable problem have been discussed at length in previous studies.  ... 
doi:10.2514/1.20433 fatcat:m7olosmynfgh5ea2znmhgeqvbm

Validation analyses of integrated procedures for evaluation of stability, buffeting response and wind loads on the Messina Bridge

A. Zasso, S. Stoyanoff, G. Diana, E. Vullo, D. Khazem, K. Serzan, A. Pagani, T. Argentini, L. Rosa, P.O. Dallaire
2013 Journal of Wind Engineering and Industrial Aerodynamics  
The topic of this paper is a comparative presentation of the results obtained by RWDI and Politecnico di Milano (POLIMI) through independent theoretical and numerical methods, on the basis of an identical  ...  C D0 K D0 C L0 K L0 Main Cables 0,52 0 0 -2.6767 Hangers 0,6 0 0 0 The quasi-static approximation was also used for the two towers.  ...  As done for the Flutter Derivatives, the quasi-static approximation was used to extrapolate the aerodynamic admittance functions coefficients and cover for drag which was not experimentally identified.  ... 
doi:10.1016/j.jweia.2013.07.013 fatcat:l4om4ugpkvhoradqlnpgplkloe

Parameter estimation for towed cable systems using moving horizon estimation

Liang Sun, Jeremy D. Castagno, John D. Hedengren, Randal W. Beard
2015 IEEE Transactions on Aerospace and Electronic Systems  
This paper presents a strategy for optimal estimation of parameters for towed cable systems using moving horizon estimation (MHE).  ...  A Pareto frontier is used to demonstrate a series of optimal experimental configurations obtained by adjusting the model complexity (number of cable links and horizon steps).  ...  Methods based on Gauss's Principle are suitable for inelastic cables, which may be inappropriate for the cable (e.g. a fishing line) used in the current experiment.  ... 
doi:10.1109/taes.2014.130642 fatcat:j4yjmicdvreo5gk5rtjnjyy5fa

Design of a High-Altitude Long-Endurance Solar-Powered Unmanned Air Vehicle for Multi-Payload and Operations

G Romeo, G Frulla, E Cestino
2007 Proceedings of the Institution of Mechanical Engineers. Part G, Journal of Aerospace Engineering  
A finiteelement method and a classical theoretical analysis was carried out using the Msc/Patran/ Nastran code to predict the static and aeroelastic behaviour of the SHAMPO.  ...  A blended wing body (BWB) configuration has been selected for solar HAVE aircraft multi payload and operation (SHAMPO) with eight brushless electric motors, as the result of a preliminary design.  ...  The distributed variables are discretized in space using the Galerkin's method.  ... 
doi:10.1243/09544100jaero119 fatcat:vfkn6cz7e5axrkjvtgllpkaocm

Cable-driven parallel mechanisms: state of the art and perspectives

2014 Mechanical Engineering Reviews  
This 1 3 scale prototype has a foot print of approximately 0.5km 2 and the cables connecting the ground winches to the aerostat have a length of approximately 400m.  ...  advanced methods [16] .  ... 
doi:10.1299/mer.2014dsm0004 fatcat:fl7f74iqw5al3nzgv642xof2sq

Wind-Induced Phenomena in Long-Span Cable-Supported Bridges: A Comparative Review of Wind Tunnel Tests and Computational Fluid Dynamics Modelling

Yuxiang Zhang, Philip Cardiff, Jennifer Keenahan
2021 Applied Sciences  
Traditionally, wind tunnel tests have been the preferred method of conducting bridge wind analysis.  ...  The focus of this paper is on long-span cable-supported bridges. Wind issues in long-span cable-supported bridges can include flutter, vortex-induced vibrations and rain–wind-induced vibrations.  ...  Compared with currently available computational capacity, these simulations would be considered nascent for using a 2D coarse mesh and approximating the near-wall behaviour using wall functions.  ... 
doi:10.3390/app11041642 fatcat:2inmxwzlhffmlmqqg4u4wc62ca

Airship Research and Development in the Areas of Design, Structures, Dynamics and Energy Systems

Casey Stockbridge, Alessandro Ceruti, Pier Marzocca
2012 International Journal of Aeronautical and Space Sciences  
Recent years have seen an outpour of revived interest in the use of airships for a number of applications.Present day developments in materials, propulsion, solar panels, and energy storage systems and  ...  simulation capabilities in CAD/CAE, CFD and FEA provided by modern computers allow an accurate design useful to optimize and reduce the development time of these vehicles.The purpose of this contribution  ...  [94] , Fluent was used to accurately simulate the motion of stratospheric airships with a model that calculated the aerodynamics of an airship based on a panel method and an engineering estimation approach  ... 
doi:10.5139/ijass.2012.13.2.170 fatcat:pu7ojc4rufgkrpiy3b5dqogn7u

Structural and Aerodynamics Analysis on Different Architectures for the Elettra Twin Flyer Prototype

M. Battipede, P. Gili, M. Vazzola
2013 Journal of Intelligent and Robotic Systems  
In this paper, the authors analyze and compare two airship configurations for the Elettra Twin Flyer prototype, an innovative airship concept which is remotely-controlled and intended for monitoring, surveillance  ...  The second architecture is a soap-shaped exoskeleton configuration which features a single inflated section, incorporating two separate elements, which are held internally by a system of ribs.  ...  The Steady Reynolds-Averaged Navier-Stokes (RANS) equations have been solved using the sequential algorithm based on the Semi-Implicit Method for Pressure Linked Equations (SIM-PLE) [17] method with  ... 
doi:10.1007/s10846-013-9823-9 fatcat:m2ye2tleh5ap7nodwmuzbxp3su

Electric power generation in wind farms with pumping kites: levelized cost of energy and sensitivity analysis

Anny Key de Souza Mendonça, Antonio Cezar Bornia
2020 Research, Society and Development  
The research makes use of the LCOE method.  ...  cost of energy of three wind farm scenarios: Classic wind farm, Wind farm with tethered airfoils operating in Pumping Kite mode and a hybrid park with the two park configurations studied.  ...  Acknowledgement The authors would like to thank the Coordination for the Improvement of Higher Education Personnel (CAPES) for funding this research project.  ... 
doi:10.33448/rsd-v9i7.4528 fatcat:g3drpxzbrra4jatyhjbdwf7ile
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