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Showing 1 to 20 of 27 for “"high speed flows"”.
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A study of unstable axisymmetric separation in high speed flows
… separation was conducted using spiked cones in flows with free stream Mach numbers, M, of 6.0 and 2.21. Reynolds numbers based on the model diameter, Re<sub>D</sub>, were 0.13x10⁶ and 0.9x10⁶ at M = 6.0 and 0.05x10⁶ and 0.12x10⁶ at M = 2.21. The body cone half angle, Φ<sub>D</sub>, for the range …
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Fundamental physics and application of plasma actuators for high-speed flows
In this dissertation, a detailed investigation is given discussing three plasma-based flow control methods. These methods included plasma generated by laser energy, microwaves, and electric arc. The plasma generated by laser energy was also applied to a sonic transverse jet in a supersonic cross …
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Validation of Conjugate Heat-Transfer Capability for Water- Cooled High-Speed Flows
… are validated against existing data for three high speed water-cooled wind tunnel experiments: i) Air Force high-enthalpy nozzle test which recorded the increase in water coolant temperature, ii) Jet Propulsion Lab converging-diverging nozzle test for which nozzle and run-up were …
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Model Reduction of Computational Aerothermodynamics for Multi-Discipline Analysis in High Speed Flows
… hypersonic cruise vehicles capable of sustained high-speed flight and access to space. However, an extensive set of technical challenges have obstructed the development of such vehicles. These technical challenges are partially due to both the inability to accurately test scaled vehicles in wind …
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Extension to Multiple Species of a Two-Equation Turbulence Model for High Speed Flows
… species and implemented in a CFD code for high speed flows using the Steger-Warming flux-vector splitting scheme. The model was chosen because compressibility corrections are not required, nor are viscous damping factors or wall functions to produce the law of the wall, and it has …
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Near wall high resolution particle image velocimetry and data reconstruction for high speed flows
… Image Velocimetry (TRDPIV) for measuring high speed, high magnification, near wall flow fields. Previous attempts to perform measurements such as this have been unsuccessful because of both limitations in equipment as well as proper methodology for processing of the data. This work …
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Exploratory Study on the Design of Combined Aero-Thermo-Structural Experiments in High Speed Flows
… analysis over long time records. High fidelity modeling over these long trajectories is prohibitively expensive computationally. In addition, validation of approximate models is limited due to the lack of experimental data capturing coupled fluid-thermal-structural interactions.The …
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Integration and Evaluation of Unsteady Temperature Gages for Heat Flux Determination in High Speed Flows
… surface temperature gages designed to operate in high speed flow. Heat flux through the surface of the test article was determined from the unsteady temperature by applying a 3D reconstruction algorithm based on a Green's function approach. The surface temperature gages used in this work were 1.59 …
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Aerothermal and aeroelastic response prediction of aerospace structures in high-speed flows using direct numerical simulation
Future high-speed air vehicles will be lightweight, flexible, and reusable. Vehicles fitting this description are subject to severe thermal and fluid dynamic loading from multiple sources such as aerothermal heating, propulsion system exhaust, and high dynamic pressures. The combination of …
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A two-dimensional fluid-structure coupling algorithm for the interaction of high-speed flows with open shells
… 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 extend the algorithm previously presented by the authors to the case of open shell structures immersed in a fluid. For simplicity, we …
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Heat Transfer, Transition, And Aerodynamic Loss In A Linear Vane Cascade At Low Reynolds Numbers In High Speed Flows
… efficiency of the modern gas turbine engine. At high altitude cruise conditions, the low pressure turbine experiences low Reynolds number flow, which produces a laminar boundary layer on airfoil surfaces. The integrity of the laminar boundary layer is highly susceptible to flow disturbances …
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Multi-scale particle transport modeling: Kinetic high-fidelity DSMC approaches and system-scale Eulerian-Lagrangian simulations for high-speed flows
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2024-03-01 without embargo terms
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Exploring a Novel Adaptive Mesh Refinement Strategy for High-Speed CFD
… that is developed and evaluated for transonic high-speed flows using Ansys Fluent. The algorithm for marking cells for adaptation is designed to systematically reduce local truncation errors based on the curvature of the primitive vector field. The algorithm for marking cells for adaptation is …
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Development of Multi-perspective Diagnostics and Analysis Algorithms with Applications to Subsonic and Supersonic Combustors
… needs for the study of hydrocarbon combustion in high speed flows: 1) combustion diagnostics with adequate temporal and spatial resolution, and 2) mathematical techniques that can extract key information from large datasets. The goal of this work is to address these needs, respectively, by the use …
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Aerodynamic Performance Enhancement of a NACA 66–206 Airfoil Using Supersonic Channel Airfoil Design
… have been shown to significantly reduce drag in high-speed flows over diamond shaped airfoils by Ruffin and colleagues. The effect of applying these techniques to a NACA 66-206 airfoil is presented. The design domain entails channel heights of 8-16.6% thickness-to-chord and speeds from Mach …
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A study of gas-solids flows at very high speed
… of suspensions of solids particles in gases at high flow velocities has been carried out. A literature survey into gas-solids flow at both low and high speeds has revealed that most of the existing work on high speed flows is of a theoretical nature and has been stimulated as a result of the …
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Spatiotemporally-Resolved Velocimetry for the Study of Large-Scale Turbulence in Supersonic Jets
… for the study of large-scale turbulence in high-speed flows. The technique has been used to demonstrate three-component velocity measurements acquired at 250 kHz, and an analysis is presented to explore the implications of scaling the technique for studying large-scale turbulent behavior. …
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Shape Matching for Reduced Order Models of High-Speed Fluid Flows
… research interest. Still, parameter dependent high-speed flows that contain shock waves are a particularly challenging class of problems that introduces many complications in ROM frameworks. To make approximations in a linear space, ROM techniques for these problems require that basis functions …
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A Study of Compressible Turbulent Free Shear Layers Using Laser Doppler Velocimetry (Supersonic Flow, Mixing, Recirculating)
… bias for two-channel coincident LDV systems in highly turbulent high speed flows was examined in detail analytically.
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Improving shock-capturing robustness for higher-order finite element solvers
Simulation of high speed flows where shock waves play a significant role is still an area of development in computational fluid dynamics. Numerical simulation of discontinuities such as shock waves often suffer from nonphysical oscillations which can pollute the solution accuracy. Grid adaptation, …
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