Designing robust control for hypersonic vehicles in reentry is difficult, due to the features of the vehicles including strong coupling, non-linearity, and multiple constraints. This paper proposed a characteristic model-based robust model predictive control (MPC) for hypersonic vehicles with reentry constraints. First, the hypersonic vehicle is modeled by a characteristic model composed of a l...

Although human beings cannot perceive elastic vibrations in the frequency range above 20 kHz, nonstationary sounds containing a wealth of inaudible high-frequency components (HFC) above the human audible range activate deep-lying brain structures, including the brainstem and thalamus and evoke various physiological, psychological, and behavioral responses. In the previous reports, we have calle...

Flow field around hypersonic vehicles is very complex and difficult to simulate. The boundary layers are squeezed between shock layer and body surface. Resolution of boundary layer, shock wave and turbulent regions where the flow field has high values is difficult of capture. Detached eddy simulation (DES) is a modification of a RANS model in which the model switches to a subgrid scale formulat...

A systematic fluid theory of nonlinear magnetic island dynamics in conventional low, large aspect-ratio, circular cross-section tokamak plasmas is developed using an extended magnetohydrodynamics model that incorporates diamagnetic flows, ion gyroviscosity, fast parallel electron heat transport, the ion sound wave, the drift wave, and average magnetic field-line curvature. The model excludes th...

Experimental and numerical results have shown that two-dimensional surface roughness can stabilize a hypersonic boundary layer dominated by second-mode instability. It is sought to understand how this physical phenomenon extends from an airflow under a perfect gas assumption to that of a real gas. To these ends, a new high-order shock-fitting method that includes thermochemical nonequilibrium a...

Several different approaches to shape optimization are explored to identify hypersonic aeroshell shapes that will increase landed mass capability by maximizing drag-area for a specified lift-to-drag ratio. The most basic approach manipulates standard parameters associated with analytic aeroshell shapes like the sphere-cone and ellipsled. More general approaches manipulate the control points of ...

This report presents a multivariable controller design for a generic missile travelling at hypersonic speed. The controller is based on the theory of optimal control, and the solution is provided by a feedback controller known as a Linear Quadratic Regulator (LQR) for tracking the demands (lateral acceleration and roll rate) as closely as possible while keeping the actuator efforts (for deflect...

Direct simulation Monte Carlo (DSMC) of shock interaction in hypersonic low density flow is developed. Three collision molecular models, including hard sphere (HS), variable hard sphere (VHS), and variable soft sphere (VSS), are employed in the DSMC study. The simulations of double-cone and Edney's type IV hypersonic shock interactions in low density flow are performed. Comparisons between DSMC...

Aiming at intercepting a hypersonic weapon in a hypersonic pursuit-evasion game, this paper presents a fractional calculus guidance algorithm based on a nonlinear proportional and differential guidance law. First, under the premise of without increasing the complexity degree of the guidance system against a hypersonic manoeuvering target, the principle that the differential signal of the line-o...

Traditional multidisciplinary design optimization methodologies of hypersonic missions often employ population-based global searching methods that rely on shooting methods to perform trajectory optimization. In this investigation, a rapid simultaneous hypersonic aerodynamic and trajectory optimization methodology is constructed based on variational methods. This methodology is constructed from ...