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Showing 1 to 20 of 25 for “"parachutes"”.
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Advanced fluid-structure interaction techniques for modeling ringsail parachutes
… problems including geometrically complex parachutes. Current modeling technologies are expanded upon with emphasis placed on more realistic FSI modeling of the Orion spacecraft ringsail parachutes. A method for generating a starting condition that matches NASA drop test data and allows for …
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Damping Effects of Drogue Parachutes on Orion Crew Module Dynamics
… the Orion Crew Module (CM) dynamics with drogue parachutes deployed are under-predicting the amount of damping as seen in free-flight tests. The Apollo Legacy Chute Damping model has been resurrected and applied to the Orion system. The legacy model has been applied to predict CM damping under …
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A Computational Fluid Dynamics Study on the Aerodynamic Performance of Ram-Air Parachutes
… and CFD methodology to the simulation of ram-air parachutes in steady-state conditions. Starting from a 2D rib drawing, methods were developed to approximate the 3D geometry and efficiently model the parachute as a rigid and impermeable body. The use of distortions was implemented on a 2D, …
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Proud to Send Those Parachutes Off: Central Utah's Rosies During World War II
<p>World War II affected individuals across the nation, both on the home front and on the front lines. Manti, Utah received a new industry, a parachute plant, in connection with the war. Hundreds of women from Sanpete County and neighboring counties were employed through the duration of the war in …
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Optimization parameters for a membrane polygonal body of revolution with zero meridional stress and its application to parachutes
A polygonal body of revolution consisting of discrete meridional members joined by regular polygons is optimized for maximum drag and drag coefficient. The meridional, or primary members, carryall of the radial loads and the membrane structure transfers applied pressure loads to the primary …
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Fluid-Structure Interaction Modeling of Parachutes with Disreefing and Modified Geometric Porosity and Separation Aerodynamics of a Cover Jettisoned to the Spacecraft Wake
… interaction (FSI) modeling of spacecraft parachutes involves a number of computational challenges. The canopy complexity created by the hundreds of gaps and slits and design-related modification of that geometric porosity by removal of some of the sails and panels are among the formidable …
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Space--Time Computation of a Ringsail Parachute With Model Thickness
… computational analysis of geometrically complex parachutes. In earlier computations, the parachutes modeled by our team did not include the fabric thickness in the fluid domain, as doing so would require a large number of elements, which is computationally costly. However, by resolving the …
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Characterizing the failure of parachute seams : the impact of stitch concentration and strain rate on ultimate tensile strength
Parachutes are commonly used in space mission landings. With increasing payloads, parachutes are getting larger, bearing larger loads and operating at faster speeds. Designing these devices requires a knowledge of aerodynamics, fluid flow, and the mechanical properties of cloth. A brief overview of …
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Optimal lift and drag modulation hypersonic control options for high ballistic coefficient entry vehicles at Mars
… relies heavily on Viking-era supersonic parachutes that are approaching their landed mass limits; however, supersonic retropropulsion (SRP) is a promising replacement for parachutes. Minimizing the propellant mass fraction (PMF) for SRP would enable larger payload masses. Maximizing the …
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Coupled Fluid-Structure Interaction Modeling of a Parafoil
… ANSYS Multiphysics can be used to model square parachutes.</p>
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Flight test of a supersonic decelerator on Earth to simulate a Mars entry
… and based on these models requirements for parachutes to be used for Mars entry are developed. Appropriate parachute model and scaling laws for Earth simulation of Mars performance are developed. A disk-gap-band parachute was selected for a flight test on Earth to simulate a mission profile …
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The development, optimisation and testing of an unmanned parafoil launch system
… when compared to conventional round parachutes. This steering ability has led to the development of autonomous control systems that are able to navigate a payload to land in close proximity to a designated landing site. In order to develop an autonomous navigation system a suitable …
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A two-dimensional fluid-structure coupling algorithm for the interaction of high-speed flows with open shells
… examples include inflatable structures and parachutes used as deceleration devices during planet entry. In this work, an algorithm for simulating the solid-fluid interactions of a highly-deformable open shell structure and a compressible fluid flow is presented. The main objective is to …
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Strain Gauge Utilization for Aerial Vehicle Dynamic Load Measurement
… system for the suspension lines of circular parachutes was developed. The motivation to create a load distribution measurement system stems from parachute system design traditionally requiring an extensive flight testing regimen. Numerical solution-based design is difficult due to the highly …
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Airbag simulation utilising Arbitrary Lagrangian Eulerian methodology for Out Of Position cases
… during deployment of slide-rafts, lifevests and parachutes.
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Essays on incentives for innovation
… incentives for innovation, while golden parachutes can alleviate these innovation-reducing effects. Finally, in Chapter 4, I investigate the choice of organizations to conduct interim performance evaluations.
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Vertical Take-Off and Landing Control via Dual-Quaternions and Sliding Mode
… landing has been most commonly accomplished with parachutes. However, in spite of their simplicity, they are susceptible to parachute drift. This parachute drift makes it very difficult to predict where the vehicle will land, especially in a dense and windy atmosphere such as Earth. Instead, …
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Preliminary Test Predictions for Scale Ram-Air Parachute Testing
… performance for experimental tests of ram-air parachutes in a wind tunnel. A scaled experimental test setup is developed for determining the aerodynamic coefficients of lift (𝐶𝐿) and drag (𝐶𝐷) conducted in a wind tunnel. Additionally, a CFD approach where a steady-state parachute shape defined …
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Viability and Validation of Near-Passive Descent Control for Quadrotor Systems
… the use of additional decelerators such as parachutes. All three methods utilize a variation of autorotation during descent to reduce the amount of energy consumed. The first method uses variable-pitch rotor blades to control the quadrotor's attitude during descent. This is shown by using a …
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