Variational algorithms for identifying power source of impulse point pollution

Authors

  • Kochergin V.S. Marine Hydrophysical Institute, Russian Academy of Science, Sevastopol, Российская Федерация
  • Kochergin S.V. Marine Hydrophysical Institute, Russian Academy of Science, Sevastopol, Российская Федерация

UDC

51.37

Abstract

The environmental situation in the Azov sea requires the establishment of reliable systems of environmental monitoring that can effectively evaluate its condition in areas exposed to technogenic impact. To obtain such information on the state of the object is the efficient application of modern computing technology. The decision of problems of different pollutions propagation in the sea is possible on the basis of methods of mathematical modeling and methods of solving inverse problems, when due to the assimilation of measurement data is required to identify certain parameters of the transport model. Currently, variational methods of assimilation and the method of adjoint equations are actively developing and are used to solve Oceanographic problems. Algorithms for data assimilation of measurements based, as a rule, on the minimization of a quadratic cost function, characterizing the deviation of model solutions from measurement data. Transport model of a passive impurity acts as constraints on variation of input parameters. In the present paper the variational methods of identifying power instantaneous point source pollution based on the solution of adjoint tasks and variational task. In addition to search for the desired value applied valuation method and the variational method of filtering of linear systems of equations. Numerical experiments were carried out using the hydrodynamic model of the Azov sea. The received fields of the currents used in the passive admixtures transport modeling. Numerical experiments have shown that using variational algorithms for identifying power instantaneous point source required a single iteration. Due to identification of the variables in the space and time parameters of the pollution source additional iterations are required. When implementing variational algorithms for identification in case of noisy measurement data is filtered. When implementing the valuation method and solving the corresponding system of equations necessary additional filtering. In General, the numerical experiments showed a reliable performance of the considered algorithms identify the power source of the contamination, in relation of transport model of passive tracer in the Azov sea.

Keywords:

variational algorithm, identification of input parameters, passive admixture, transport model, Azov Sea, transport and diffusion of pollutions, assimilation of data measurements

Acknowledgement

Работа выполнена в рамках государственного задания по теме № 0827-2014-0010 "Комплексные междисциплинарные исследования океанологических процессов, определяющих функционирование и эволюцию экосистем Черного и Азовского морей, на основе современных методов контроля состояния морской среды и гридтехнологий".

Author Infos

Vladimir S. Kochergin

младший научный сотрудник отдела теории волн Морского гидрофизического института РАН

e-mail: vskocher@gmail.com

Sergey V. Kochergin

старший научный сотрудник, отдела морских информационных систем и технологий, Морского гидрофизического института РАН

e-mail: vskocher@gmail.com

References

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Issue

Section

Physics

Pages

67-72

Submitted

2017-08-28

Published

2017-09-30

How to Cite

Kochergin V.S., Kochergin S.V. Variational algorithms for identifying power source of impulse point pollution. Ecological Bulletin of Research Centers of the Black Sea Economic Cooperation, 2017, no. 3, pp. 67-72. (In Russian)