Wyniki wyszukiwania - BazTech

1

Zagadnienia fotoniki w badaniach wpływu materiałów okrętowych na środowisko morskie

Baszanowska E., Freda W., Otremba Z., Rudź K., Stelmaszewski A., Targowski W., Toczek H.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2013

|

nr 81

5--22

PL

Informacje o procesach zachodzących w toni wodnej przenoszone są w promieniowaniu elektromagnetycznym tylko w jego paśmie widzialnym. Wtrącenia substancji obcych w środowisku wodnym zaburzają naturalny transfer energii promienistej. Okrętowe materiały eksploatacyjne – głównie oleje i paliwa – w przypadku przedostania się do środowiska morskiego wpływają na modyfikację rozkładów prawdopodobieństwa oddziaływań fotonów z wodą i jej składnikami. W niniejszym artykule przedstawiono najważniejsze pojęcia, zjawiska oraz procesy optyczne w środowisku morskim o podwyższonej zawartości substancji ropopochodnych.

EN

Information on natural processes in the water column is transmitted by electromagnetic radiation in the visual range only. Various anthropogenic, alien for marine environment, substances disturb natural transport of the radiant energy. Ship consumables as fuels and lubricants (oils) when entering the marine environment – influences probability distributions of interactions between the solar photons and water constituents. In this paper main phenomena and photonic processes in the environment polluted by oil substances are described.

2

Estimation of emulsified and dissolved oil content in seawater

Rudź K., Toczek H.

Journal of KONES

|

2013

|

Vol. 20, No. 1

287--293

EN

The demand to control the amount of oil discharged to the seawater is the consequence of increasing shipping activities. Oil products enter marine environment on daily basis in the form of fuels, engine oils or crude oils. Each of them have a significant impact on marine life and the coastal water management. Oil content influences many environmental factors, like water quality and bio-optical parameters (e.g. water-leaving radiance, inherent optical properties, seawater fluorescence). It should be measured on regular basis to avoid over or underestimation of those parameters. Currently there are several methods used to estimate the total hydrocarbon content in seawater, mostly based on fluorescence measurements. We present a unique method suitable to determine the concentration of oil products in two forms: the amount of dissolved oil and the amount of oil-in-water emulsion. The method consist of several steps: seawater sampling, vacuum filtering, extracting of oil in n-hexane, fluorescence measurements and calculation of oil concentration in comparison to the reference samples, i.e. the solutions of different types of crude oil in n-hexane. The results have been measured for the samples collected in Southern Baltic Sea during several ship cruises in 2012. We discuss the advantages and disadvantages of presented method in the context of radiative transfer modelling and potential remote detection of dispersed oil.

3

Model of seawater polluted by oil-in-water emulsion as a response to the increasing shipping activities

Rudź K.

Journal of Polish CIMAC

|

2012

|

Vol. 7, no 1

209-217

EN

Intensive shipping affects marine environment in an extent degree, increasing seawater pollution by hazardous substances, including fuel oil and crude oil. Bilge water from ship power plants usually contains a mixture of dispersed oils, which form spherical droplets of diameter ranging from 0.01 to 10..m. Present methods for detection of dispersed oil require taking a water sample or putting a measuring device into seawater, which allows only to gather point data from limited locations. In order to meet the demand of remote monitoring of endangered zones, a study of optical properties of oil-in-water emulsions was conducted. Presented model of seawater polluted by oil-in-water emulsion can potentially enable remote optical detection of oil-in-water emulsion in visible bands. It is based on the fact that oil droplets become additional absorbents and attenuators in water body. Optical analyses consist of calculations of spectral absorption and scattering coefficients and scattering phase functions for oil emulsions on the basis of Lorentz-Mie theory including measurements of refractive index and determination of oil droplets size distribution. The radiative transfer theory is applied to simulate the contribution of oil emulsion to the remote sensing reflectance. Presented system for radiative transfer simulation is based on Monte Carlo code and it involves optical tracing of virtual photons.

4

Modelling of seawater polluted by light and heavy crude oil droplets

Rudź K., Darecki M., Toczek H.

Journal of KONES

|

2012

|

Vol. 19, No. 2

473-480

EN

Significant amounts of crude oil transported from offshore fields to the refineries using tankers or pipelines, demand increased control of seawater pollution. Tanker accidents resulting in oil spills drive much attention, as they influence local marine life and coastal industry. However, the most significant annual amount of crude oil enters the sea in the form of oilin- water emulsion as a result of standard tanker operations, offshore oil extraction and daily work of refineries. Many branches of science are challenged to provide new methods for oil detection, less expensive, more sensitive and more accurate. Remote satellite or airborne detection of large oil spills is possible using joint techniques as microwave radars, ultraviolet laser fluorosensors and infrared radars. Some methods are capable to deal with oil streaks detection and estimation of oil thickness. Although there is currently, no method to detect small concentration of oil droplets dispersed in seawater. Oil droplets become additional absorbents and attenuators in water body. They significantly change seawater inherent optical properties, which imply the change of apparent optical properties, detectable using remote sensing techniques. To enable remote optical detection of oil-in-water emulsion, a study of optical properties of two types of crude oil was conducted. Radiative transfer theory was applied to quantify the contribution of oil emulsion to remote sensing reflectance (Rrs). Spectra of Rrs from in situ measurements in Baltic Sea were compared to Rrs spectra of seawater polluted by 1 ppm of crude oil emulsion, collected using radiative transfer simulation. The light crude oil caused a 9-10% increase of Rrs while the heavy one reduced Rrs up to 30% (model accuracy stayed within 5% for considered spectral range). Results are discussed concerning their application to shipboard and offshore oil content detection.

5

Skutki zrzutu olejowego w polu światła w morzu

Rudź K.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2010

|

nr 64

99-108

PL

Wody zrzutowe pochodzące z siłowni okrętowych zawierają substancje olejowe, które dostają się do środowiska morskiego w postaci rozpuszczonej oraz zdyspergowanej, w następstwie czego zmieniają warunki transferu energii promienistej w toni morskiej. W artykule przedstawiono jakościową i ilościową analizę porównawczą tzw. pozornych właściwości optycznych czystej i zanieczyszczonej wody morskiej na przykładzie reflektancji oświetlenia, dla modelu akwenu bałtyckiego i akwenu oceanicznego. Kątowe rozkłady radiacji nadwodnej dla wybranych modeli środowiska morskiego otrzymano metodą komputerowej symulacji losów wielkiej liczby fotonów (ang. photon trace simulation). Przeprowadzono symulacje dla dwóch rodzajów substancji ropopochodnych o skrajnie różnych właściwościach optycznych, dla długości fal z zakresu światła widzialnego, dla różnych wysokości słońca. Wyniki przedstawiono w postaci zależności widmowych i kątowych reflektancji oświetlenia obliczonej poprzez definicyjne całkowanie rozkładów oddolnej radiacji.

EN

Discharge waters coming from ship plants contain small amount of oil substances which enter the marine environment in the form of dispersed droplets (emulsion). It has been proven that small concentrations of oil-in-water emulsion cause significant changes of seawater optical properties. This paper presents a comparative analysis of apparent optical properties for unpolluted and polluted seawater. Irradiance reflectance was calculated for both models of marine basins: the Baltic and oceanic one. Angular distribution of upwelling radiance was received from a computed photon trace simulation (based on the Monte Carlo code) for selected models of the marine environment. Simulations were performed with two types of petroleum substances, each with extremely different optical properties, for nine wavelengths selected from the visible light spectrum and for various sun height above the horizon. Inherent optical properties of seawater and oils, as well as angular scattering functions and oil droplets' size distributions, have been obtained mainly in the laboratory and partly adopted from specialist literature. Results are presented in the form of sun-height and spectral dependences of irradiance reflectance. The values of irradiance reflectance have been calculated by the integration of simulated upwelling radiance distributions.

6

Ocean optics in application to remote detection of an oil-in-water emulsion originating from the engine room

Otremba Z., Rudź K.

Journal of KONES

|

2010

|

Vol. 17, No. 3

349-353

EN

Relatively great number of detected and confirmed oil spillages in the Polish marine areas reveals that discharge of oil substances from any one of a large number of ships to the marine environment is real in any time. Surface oil contamination can be easily detected by satellite or airborne radar techniąues, but unfortunately oil dispersed in the bulk of water cannot be detected at the present. Discharge waters usually contain small amounts ofoil substances in the form of dispersed droplets (emulsion). It is revealed that oil emulsion cause measurable changes in the optical properties of seawater. In practice, detection of changes of these properties should be possible by the standard radiance or irradiance reflectance meter. This paper presents a computed photon trace simulation applied to the marine environment polluted by oil-in-water emulsion. Model of marine area consists ofwhether conditions, sun elevation, sea depth, optical properties of seawater related to various transparency/turbidity: from clean oceanic waters to turbid coastal seawater (as water from Gulf of Gdańsk is). Model of oil pollution is represented by oil droplets size distribution and by spectra of both attenuation-coefficient and refraction-coefficient related to two optically absolutely different kinds of oil. It is revealed that the values of irradiance reflectance are significantly differ for the clean sea area in relation to the polluted one, even for small amounts of engine-room origin oil pollution.