Proper Orthogonal Decomposition for Three-Dimensional Membrane Wing Aerodynamics

In this paper, classic Proper Orthogonal Decomposition (POD) on a polar coordinate and snapshot POD on a Cartesian grid will be applied separately in the near field of a turbulent wall jet. Three-component stereoscopic PIV measurements are performed in the transverse plane of a wall jet formed using a round contoured nozzle with a Reynolds number of 250,000. Eigenfunctions and energy distributions of the two methods are compared. Reconstructions using same number of modes and same content of energy have been compared. The effect of grid resolution on the energy content of the classic method has also been studied.

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Characteristics of Turbulent Three-Dimensional Wall Jets

Journal of Fluids Engineering ◽

10.1115/1.4003277 ◽

2011 ◽

Vol 133 (2) ◽

Cited By ~ 16

Author(s):

M. Agelin-Chaab ◽

M. F. Tachie

Keyword(s):

Proper Orthogonal Decomposition ◽

Three Dimensional ◽

Reynolds Numbers ◽

Orthogonal Decomposition ◽

The Self ◽

Shear Stresses ◽

Spread Rate ◽

Similar Region ◽

Self Similar ◽

Proper Orthogonal

Three-dimensional turbulent wall jet was investigated using a particle image velocimetry technique. Three Reynolds numbers based on the jet exit velocity and diameter of 5000, 10,000, and 20,000 were studied. Profiles of the mean velocities, turbulence intensities, and Reynolds shear stresses as well as two-point velocity correlations and proper orthogonal decomposition analyses were used to document the salient features of the wall jets. The decay and spread rates are independent of Reynolds numbers in the self-similar region. The estimated values of 1.15, 0.054, and 0.255 for the decay rate, wall-normal spread rate, and lateral spread rate, respectively, are within the range of values reported in the literature. The two-point correlation analysis showed that the inclination of the streamwise velocity correlation contours in the inner layer is 11±3 deg in the wall region, which is similar to those of canonical turbulent boundary layers. The results from the proper orthogonal decomposition indicate that low-order modes contribute more to the turbulence statistics in the self-similar region than in the developing region. The Reynolds shear stresses are the biggest benefactors of the low-order mode contribution while the wall-normal turbulence intensities are the least.

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Rapid Transient Thermal Analysis of Three-Dimensional Interconnect Structures Using Proper Orthogonal Decomposition Method

ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2012-75286 ◽

2012 ◽

Author(s):

Banafsheh Barabadi ◽

Satish Kumar ◽

Yogendra K. Joshi

Keyword(s):

Thermal Analysis ◽

Proper Orthogonal Decomposition ◽

Joule Heating ◽

Hot Spot ◽

Three Dimensional ◽

Orthogonal Decomposition ◽

Computational Time ◽

Interconnect Architectures ◽

High Level ◽

Proper Orthogonal

The increase in the integration of interconnect wiring, as well as the high level of current densities are resulting in increased concerns about hot spot formation due to Joule heating in the metal lines of microprocessors. This temperature rise poses a major challenge in maintaining the quality and reliability of future devices, requiring a focus on physics based approaches for rapid and accurate thermal analysis of interconnect architectures. This work investigates the problem of transient Joule heating in a three-dimensional array of copper interconnects embedded in dielectric layers of SiO2 and Si3N4 using Proper Orthogonal Decomposition (POD) as the reduced order modeling approach. The case of natural convection was assumed on the boundaries. For validation, the results were compared with a three-dimensional finite volume model developed in Fluent and good agreements models were observed. While the Fluent model required hours of computational time, the POD based model predictions were achieved within seconds.

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