Search NASA⌕ Search

SEARCH · Search NASA

Results for “Nonlinear Analysis”

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.

At least 361 records · Page 20
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Analysis of nonlinear optical propagation in a longitudinal deuterated potassium dihydrogen phosphate Pockels cell

Nonlinear optical propagation in a longitudinal deuterated potassium dihydrogen phosphate (DKDP) Pockels cell (PC) is studied analytically and with numerical simulations. Propagation equations are developed taking into account the nonlinear susceptibility tensor and the modification of the polarization state because of the voltageinduced birefringence of the Pockels cell. The analytical predictions are in good agreement with split-step simulations. The nonlinear polarization in the PC’s crystalline medium leads to nonlinear phase shifts and crossed-wave generation. For the small nonlinearities consistent with typical operation in a laser system, a quarter-wave PC induces a nonlinear phase equal to the average of the nonlinear phase accumulated by a linearly and circularly polarized field of the same intensity propagating in the inactive PC. The contrast of a half-wave PC between crossed polarizers is not decreased by the nonlinear propagation because there is no generated cross wave in this configuration.

Electro-optical devices↗
NASA NTRS1971

High-impact dynamic-response analysis of nonlinear structures

Program predicts expected deformations and stresses in nonlinear simple geometric structures subjected to high-impact loading. Technique is based on node-wise predictor-corrector approach and requires moderate computer storage and run time for most problems. Program extends to include physical and geometrical nonlinearities.

Gupta, K. K.↗
NASA NTRS1972

Lagrangian methods in the analysis of nonlinear wave interactions in plasma

An averaged-Lagrangian method is developed for obtaining the equations which describe the nonlinear interactions of the wave (oscillatory) and background (nonoscillatory) components which comprise a continuous medium. The method applies to monochromatic waves in any continuous medium that can be described by a Lagrangian density, but is demonstrated in the context of plasma physics. The theory is presented in a more general and unified form by way of a new averaged-Lagrangian formalism which simplifies the perturbation ordering procedure. Earlier theory is extended to deal with a medium distributed in velocity space and to account for the interaction of the background with the waves. The analytic steps are systematized, so as to maximize calculational efficiency. An assessment of the applicability and limitations of the method shows that it has some definite advantages over other approaches in efficiency and versatility.

Galloway, J. J.↗