Thermal Structures for Aerospace Applications

The aeroelastic and aerothermoelastic behavior of three-dimensional configurations in hypersonic flow regime are studied. The aeroelastic behavior of a low aspect ratio wing, representative of a fin or control surface on a generic hypersonic vehicle, is examined using third order piston theory, Euler and Navier-Stokes aerodynamics. The sensitivity of the aeroelastic behavior generated using Euler and Navier-Stokes aerodynamics to parameters governing temporal accuracy is also examined. Also, a refined aerothermoelastic model, which incorporates the heat transfer between the fluid and structure using CFD generated aerodynamic heating, is used to examine the aerothermoelastic behavior of the low aspect ratio wing in the hypersonic regime. Finally, the hypersonic aeroelastic behavior of a generic hypersonic vehicle with a lifting-body type fuselage and canted fins is studied using piston theory and Euler aerodynamics for the range of 2.5 ≤ M ≤ 28, at altitudes ranging from 10,000 feet to 80,000 feet. This analysis includes a study on optimal mesh selection for use with Euler aerodynamics. In addition to the aeroelastic and aerothermoelastic results presented, three time domain flutter identification techniques are compared, namely the moving block approach, the least squares curve fitting method, and a system identification technique using an Auto-Regressive model of the aeroelastic system. In general, the three methods agree well. The system identification technique, however, provided quick damping and frequency estimations with minimal response record length, and therefore offers significant reductions in computational cost. In the present case, the computational cost was reduced by 75%. The aeroelastic and aerothermoelastic results presented illustrate the applicability of the CFL3D code for the hypersonic flight regime.

show abstract

“…9, is determined from an energy balance of the heat fluxes at the wall of the structure: 60,61 q aero =q rad +q cond +q strd (24) whereq…”

Section: -59mentioning

confidence: 99%

Three-dimensional Aeroelastic and Aerothermoelastic Behavior in Hypersonic Flow

McNamara

Friedmann

Powell

et al. 2005

46th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference

View full text Add to dashboard Cite

show abstract

“…For example [6], when solar radiation is incident at an angle upon a space structure, the absorbed radiation will either increase or decrease as the structure bends toward or away from the incoming radiation. This sets up a feedback loop that can lead either to static bending or to bending vibrations (limit cycle oscillations.)…”

mentioning

confidence: 99%

Limit Cycle Oscillations in CW Laser-Driven NEMS

Aubin

Zalalutdinov

Alan

et al. 2004

J. Microelectromech. Syst.

View full text Add to dashboard Cite

Abstract-Limit cycle, or self-oscillations, can occur in a variety of NEMS devices illuminated within an interference field. As the device moves within the field, the quantity of light absorbed and hence the resulting thermal stresses changes, resulting in a feedback loop that can lead to limit cycle oscillations. Examples of devices that exhibit such behavior are discussed as are experimental results demonstrating the onset of limit cycle oscillations as continuous wave (CW) laser power is increased. A model describing the motion and heating of the devices is derived and analyzed. Conditions for the onset of limit cycle oscillations are computed as are conditions for these oscillations to be either hysteretic or nonhysteretic. An example simulation of a particular device is discussed and compared with experimental results.[1190]Index Terms-Finite element method (FEM), laser drive, limit cycle oscillation, self-oscillation, thermal stress.

show abstract

“…This kind of thermally induced vibration of flexible space structures has been a recurring problem in the past. 1) As an example, the phenomenon that occurred to the HST. The solar arrays of the HST launched into low orbit in April 1990 were based on a flexible rolled-up solar array (FRUSA).…”

Section: Introductionmentioning

confidence: 99%

Vibration Characteristics and Thermal Structural Dynamic Responses of a Flexible Rolled-up Solar Array

Lee¹,

Murozono²

2011

Trans. Japan Soc. Aero. S Sci.

View full text Add to dashboard Cite

Analytical studies of the natural vibration characteristics and dynamic response for a simple model of an asymmetric flexible rolled-up solar array are presented. A natural vibration analysis of the solar array model including bendingtorsion coupling due to geometric asymmetry provides natural frequencies and mode shapes. Unusual features of the lower mode frequencies and mode shapes are discussed. The dynamic response of the solar array induced by sudden radiation heating for a typical night-day orbital transition is formulated. Additionally, numerical calculations are conducted for the solar array of the Hubble Space Telescope (HST). Variations of the dynamic response with the axial preload forces of the solar array booms are examined, and the vibration response due to the radiation heating of the HST solar array is discussed.

show abstract

Thermal Structures for Aerospace Applications

Cited by 190 publications

References 20 publications

Three-dimensional Aeroelastic and Aerothermoelastic Behavior in Hypersonic Flow

Three-dimensional Aeroelastic and Aerothermoelastic Behavior in Hypersonic Flow

Limit Cycle Oscillations in CW Laser-Driven NEMS

Vibration Characteristics and Thermal Structural Dynamic Responses of a Flexible Rolled-up Solar Array

Contact Info

Product

Resources

About