TECHNIQUES FOR SIMULATION AND ANALYSIS OF SHOCK AND VIBRATION ENVIRONMENTS OF SPACE FLIGHT SYSTEMS
Simulation & analysis of shock & vibration environments of space flight systems
SHOCK↗
SEARCH · Search NASA
Results for “Simulation System”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
TECHNIQUES FOR SIMULATION AND ANALYSIS OF SHOCK AND VIBRATION ENVIRONMENTS OF SPACE FLIGHT SYSTEMS
Simulation and analysis of shock and vibration environments in space-flight systems
SHOCK SIMULATOR↗
Characteristics of flight simulator visual systems
The physical parameters of the flight simulator visual system that characterize the system and determine its fidelity are identified and defined. The characteristics of visual simulation systems are discussed in terms of the basic categories of spatial, energy, and temporal properties corresponding to the three fundamental quantities of length, mass, and time. Each of these parameters are further addressed in relation to its effect, its appropriate units or descriptors, methods of measurement, and its use or importance to image quality.
Statler, I. C.↗
Quantitative Power System Resilience Metrics and Evaluation Approach
Power system resilience is an emerging topic and plays an essential role in helping the power industry understand and respond to the increasing threats of extreme weather events. The first step of power system resilience analysis is to introduce metrics to quantify the resilience reasonably. Existing resilience metrics are typically restrained by the limited data for extreme event modeling and fall short in terms of physical interpretation and comparability. This paper develops novel quantitative metrics to evaluate power system resilience in pre- and post-event contexts. The developed metrics illustrate clear physical meanings and can be effectively used to compare resilience across different systems under different extreme events. Moreover, the developed metrics can be applied to both transmission and distribution systems. Simulation on a distribution system is employed to validate the effectiveness of the proposed resilience metrics and resilience evaluation approach.
power system resilience↗
Safer Weightlessness Simulator
System described in report simulates weightlessness of space for training of astronauts, without adverse effects of rapid decompression. As in previous simulators, trainee wearing space-suit performs training exercises while immersed in water. In new system, space-suit interior is not above atmospheric pressure. No need for trainee to undergo gradual decompression to prevent bends after lengthy exercise; nor is there need for medical team to be present.
Vykukal, Hubert C.↗
Comparison of Two Models for Damage Accumulation in Simulations of System Performance
A comprehensive simulation study of system performance needs to address variations in component behavior, variations in phenomenology, and the coupling between phenomenology and component failure. This paper discusses two models of this: 1. damage accumulation is modeled as a random walk process in each time history, with component failure occurring when damage accumulation reaches a specified threshold; or 2. damage accumulation is modeled mechanistically within each time history, but failure occurs when damage reaches a time-history-specific threshold, sampled at time zero from each component’s distribution of damage tolerance. A limiting case of the latter is classical discrete-event simulation, with component failure times sampled a priori from failure time distributions; but in such models, the failure times are not typically adjusted for operating conditions varying within a time history. Nowadays, as discussed below, it is practical to account for this. The paper compares the interpretations and computational aspects of the two models mentioned above.
42 ENGINEERING↗
Simulation studies of the supersonic transport in future air traffic control systems
Simulation studies of supersonic transports in future air traffic control systems
Mc Laughlin, M. D.↗
Simulation Studies of SST Terminal Area Navigation in the ATC System
Simulation studies of supersonic transport arrival and departure operations and air traffic control problems under high density conditions
AIR TRAFFIC CONTROL↗
The data system dynamic simulation /DSDS/
The paper describes the development by NASA of the data system dynamic simulation (DSDS) which provides a data system simulation capability for a broad range of programs, with the capability to model and simulate all or any portion of an end-to-end data system to multiple levels of fidelity. Versatility is achieved by specifying parameters which define the performance characteristics of data system components, and by specifying control and data paths in a data system. DSDS helps reduce overall simulation cost and the time required for obtaining a data systems analysis, and helps provide both early realistic representations of data systems and the flexibility to study design changes and operating strategies.
Hooper, J. W.↗
A comparison of two algorithms for simulating collisionless systems
Two completely different simulation algorithms are compared by applying them to the same stellar dynamical problems: one is a self-consistent field (SCF) method for solving Poisson's equation and the other is a phase-space method for integrating the collisionless Boltzmann equation. We consider simulations of spherical stellar systems which are initially far from equilibrium and relax to their final states by gravitational collapse. The initial conditions consist of either uniform-density spheres or nonequilibrium models having Plummer density profiles, in which velocity dispersions are assigned according to given virial ratios. If a few tens of radial expansion terms with hundreds of thousands of particles are used in the SCF code, excellent agreement is found between the results it generates and those obtained with the phase-space solver, provided that a sufficiently large number of grid cells are employed with the latter. These findings imply that for simulating collisionless systmes over many dynamical times, the SCF approach based on sampling phase space is competitive with the approach treating phase space as a continuous fluid. The results of our tests make it possible to estimate the number of particles and basis functions required in situations like those modeled. Limitations of the SCF method and the choice of an optimal set of basis functions are also discussed.
Hozumi, Shunsuke↗
Real-Time Simulation Computation System
The Real-Time Simulation Computation System, which will provide the flexibility necessary for operation in the research environment at the Ames Research Center is discussed. Designing the system with common subcomponents and using modular construction techniques enhances expandability and maintainability qualities. The 10-MHz series transmission scheme is the basis of the Input/Output Unit System and is the driving force providing the system flexibility. Error checking and detection performed on the transmitted data provide reliability measurements and assurances that accurate data are received at the simulators.
Fetter, J. L.↗
Computer systems analysis methodology - Studies in measuring, evaluating, and simulating computer systems
Computer systems analysis and simulation studies on design, development, and management of complex computer systems
Boehm, B. W.↗
Simulating Open Quantum Systems Using Hamiltonian Simulations
We present a novel method to simulate the Lindblad equation, drawing on the relationship between Lindblad dynamics, stochastic differential equations, and Hamiltonian simulations. We derive a sequence of unitary dynamics in an enlarged Hilbert space that can approximate the Lindblad dynamics up to an arbitrarily high order. This unitary representation can then be simulated using a quantum circuit that involves only Hamiltonian simulation and tracing out the ancilla qubits. There is no need for additional postselection in measurement outcomes, ensuring a success probability of one at each stage. Our method can be directly generalized to the time-dependent setting. We provide numerical examples that simulate both time-independent and time-dependent Lindbladian dynamics with accuracy up to the third order. Published by the American Physical Society 2024
Ding, Zhiyan (ORCID:000000018863403X)↗
Marshall system for aerospace simulation
Software system allow facilitates quick and relatively easy simulations of physical systems on digital computers. Language is simple and flexible, and can be used by people who have little or no familiarity with computer programming.
Trauboth, H. H.↗
Development and Integration of a Thermal Management Simulation for a Quadrotor Parallel Hybrid Propulsion System
This paper details the development of a propulsion system simulation for a six-passenger parallel hybrid quadrotor and utilizes the Numerical Propulsion System Simulation (NPSS) along with the NPSS Power System Library as the development environment. This simulation integrates an engine power plant with an electrical generation and distribution system and includes the required thermal management system. The thermal management system is comprised of liquid cooling loops that reject the heat load through air to coolant heat exchangers and utilizes a map-based performance estimation method. This method is developed within NPSS and detailed in this paper. The full system model is designed to predict system weight, range, and performance through a proposed mission profile. Results of the paper show an all-engine system maintains the best range, while a mostly electric system that utilizes an engine as a backup or a conditional power contributor offers range benefit.
Vertical lift and take off vehicle↗
Development and Integration of a Thermal Management Simulation for a Quadrotor Parallel Hybrid Propulsion System
This paper details the development of a propulsion system simulation for a six-passenger parallel hybrid quadrotor and utilizes the Numerical Propulsion System Simulation (NPSS) along with the NPSS Power System Library as the development environment. This simulation integrates an engine power plant with an electrical generation and distribution system and includes the required thermal management system. The thermal management system is comprised of liquid cooling loops that reject the heat load through air to coolant heat exchangers and utilizes a map-based performance estimation method. This method is developed within NPSS and detailed in this paper. The full system model is designed to predict system weight, range, and performance through a proposed mission profile. Results of the paper show an all-engine system maintains the best range, while a mostly electric system that utilizes an engine as a backup or a conditional power contributor offers range benefit.
Vertical lift and take off vehicle↗
Simulation of a single-server model for a paging drum channel system
Simulation of single-server model for paging drum channel system
Kwok, G.-Y.↗
CFD Simulation of the Dosing Behavior within the Atomic Layer Deposition Feeding System
The effective operation of atomic layer deposition (ALD) feeding system is the premise of realizing specific ALD processes. In the present work, a detailed computational fluid dynamics (CFD) model of the feeding system has been developed and validated, which accounts for the roles of ALD valves and manifolds. A numerical simulation of the compressible fluid flow and heat/mass transfer within the feeding system was conducted. The dosing amounts and the spatiotemporal distributions of the precursors can be accurately predicted using the CFD model, as validated by experimental results. Different precursors, operating conditions, and structures of the feeding system were simulated and analyzed to examine the operating flexibility of the feeding system. The simulation results can be adopted as the upstream boundary conditions for simulations of the ALD process in the reaction chamber. The substrate-scale simulation indicates that the effect of the feeding system on the film deposition is highly related to the surface kinetics of ALD. The present work can serve as a guide for the development and optimization of different ALD-based processes via proper operation and even the design of the feeding system.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗