Linear and nonlinear phenomena with resonating surface polariton waves and their applications

Author(s):  
Haim Grebel
2020 ◽  
Author(s):  
EUGENE ADIUTORI

Conventional engineering science should be abandoned because: Engineering laws that are proportional equations (such as q = hT) cannot describe nonlinear phenomena (such as boiling heat transfer). Engineering laws were created by assigning dimensions to numbers, in violation of the conventional view that dimensions must not be assigned to numbers. Contrived parameters (such as heat transfer coefficient) make it impossible to solve nonlinear problems with the variables separated, greatly complicating solutions. All engineering equations are irrational because they attempt to describe how the numerical values and dimensions of parameters are related, when in fact equations can rationally describe only how numerical values are related. In the new engineering science described herein: Engineering laws do describe proportional, linear, and nonlinear phenomena. No engineering laws were created by assigning dimensions to numbers. There are no contrived parameters (such as heat transfer coefficient), and therefore nonlinear problems are solved with the variables separated. All engineering equations are rational because they describe only how the numerical values of parameters are related.


2013 ◽  
Vol 198 ◽  
pp. 669-674 ◽  
Author(s):  
Cezary Orlikowski ◽  
Rafał Hein

In this paper the method of modelling a speed-varying geared rotor system is presented. The proposed approach enables us to obtain an accurate low-order lumped parameter representation of the investigated system. The final model consists of reduced modal models of an undamped beam/torsional shaft system as well as a spatially lumped model of other linear and nonlinear phenomena including gear mesh interaction.


1986 ◽  
Vol 64 (9) ◽  
pp. 1269-1275 ◽  
Author(s):  
Grover C. Wetsel Jr. ◽  
James B. Spicer

Nonlinear phenomena have been observed during photothermal-optical-beam-deflection imaging experiments on samples of both high-purity aluminum and aluminum alloys. Evidence for nonlinear optical and thermal effects have been measured. Theoretical models have been developed as aids in understanding the different contrast mechanisms observed in linear and nonlinear photothermal images.


Author(s):  
Xiaoyao Shen ◽  
Jianping Jing ◽  
Qimiao Gong

Linear and nonlinear dynamics and stability of the rotor-bearing-seal system are investigated both theoretically and experimentally. First the system is modeled with the finite element method. The rotordynamic behavior of the journal bearing and the labyrinth seal are represented by eight linearized dynamic force coefficients. An experimental rotor-bearing-seal device is designed and tests are carried out. The experimental system is studied using the developed linear equations. Complex eigenvalues are solved. Corresponding critical speeds and logarithmic decrements to determine the thresholds of instability are calculated. Then the experimental rotor system is simplified as the Jeffcott rotor. The nonlinear oil-film forces are got under the short bearing theory and Muszynska nonlinear seal force model is used. Numerical method is utilized to solve the nonlinear governing equations. Bifurcation diagrams, Poincare´ maps, spectrum plots and rotor orbits are drawn to analyze various nonlinear phenomena and system unstable process. Theoretical results from the linear and nonlinear analysis are in good agreement with results from experiments. Conclusions are drawn and prove that this study will contribute to the further understanding of dynamics and stability of the rotor system with the fluid-induced forces from oil-film bearings and the seals.


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