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Parametrisation of Gas Flares Using FireBIRD Infrared Satellite ImagerySoszynska, Agnieszka Kazimiera 03 September 2021 (has links)
Bei der Förderung von Erdöl wird auch Erdgas gefördert, das oft abgefackelt wird. Das Abfackeln von Erdgas ist sehr schädlich für die Umwelt und die Bewohner einer Umgebung in der Gas abgefackelt wird. Demzufolge ist die Reduktion dieses Prozesses eine wichtige Aufgabe, die durch Monitoring von Gasfackeln unterstützt werden kann. Dies gelingt am besten durch Fernerkundung mit Satellitendaten.
Die vorliegende Dissertation widmet sich der Parametrisierung von Gasfackeln anhand von Infrarot-Satellitenaufnahmen. Eine Gruppe von Sensoren wurde verglichen, woraus optimale Eigenschaften eines Sensors zur Gasfackelanalyse abgeleitet wurden. Danach wurde ein Modell zur Berechnung des Gasflusses aus Infrarot-Satellitenaufnahmen entwickelt. Das vorgeschlagene Modell basiert auf der Physik der Verbrennung und wird von Teilmodellen zur Berechnung der Verbrennungsparameter unterstütz. Dadurch werden Prozesse mitberücksichtigt, die bisher in der Gasfackelforschung wenig adressiert wurden.
Eine Experimentenreihe erlaubte eine Charakterisierung der Flamme in Bezug auf sich verändernde Bedingungen, z.B. Gasfluss. Zusätzlich wurde das Modell durch die Experimente validiert. Die abgeleitete Genauigkeit der Gasflusswerte ist verhältnismäßig hoch, insbesondere wenn man die Komplexität und Variabilität einer Gasflamme berücksichtigt.
Durch Analysieren des Sensordesigns des BIROS Sensors aus der FireBIRD-Mission des Deutschen Zentrums für Luft- und Raumfahrt konnten die Sensorparameter charakterisiert und deren Einfluss auf ein abgeleitetes Bildprodukt quantifiziert werden. Die Fähigkeit des Modells mit unterschiedlichen Sensordaten zu funktionieren, wurde geprüft durch einen Vergleich der geschätzten Gasflusswerte aus Daten von zwei Satellitensensoren. Die verglichenen Gasflusswerte sind sehr ähnlich, was die Fähigkeit des Models mit unterschiedlichen Daten gut zu funktionieren, bestätigt.
Das vorgeschlagene Model hat Potenzial, das globale Monitoring von Gasfackeln zu verbessern. / Routine gas flaring is harmful to the environment and people living in the vicinity of gas flares. Therefore, the reduction of this process is an important task, which can be supported by monitoring of gas flares, which can be done with remote sensing techniques.
The presented work is devoted to the monitoring of gas flaring. The first aspect of the analysis was to compare a group of sensors with respect to the features crucial for gas flaring analysis. A set of requirements for an optimal sensor for this purpose was proposed. Next, a model for calculating gas flow from infrared satellite imagery was proposed, which relies on several other models, allowing to derive the values of the combustion parameters. By modelling these parameters in a gas flare, processes are accounted for that were scarcely addressed in the research conducted on gas flaring until now. To describe the characteristics of the flame coming from combustion in a flare, an experimental series was designed and conducted.
The experimental series allowed to characterise the flame with respect to changing conditions, e.g. gas flow. Thus, the characteristics derived from the experiments could be included in the model for gas flow calculation. Additionally, the experiments served as a mean to validate the model. The accuracy of the derived gas flow values is relatively high, especially considering the variability of a gas flare flame.
One design goal of the model for gas flow calculation was to ensure feasibility to work with data from different sensors producing equally accurate results. By analysing the design of the BIROS sensor of the DLR, the sensor parameters could be described, and their influence on the resulting imagery could be quantified. The feasibility was verified by comparing the gas flow values calculated using data from two different satellite sensors. The results obtained are very similar.
The model proposed reveals potential to improve the global monitoring of gas flaring.
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Estudo em múltiplas frequências da baixa atmosfera solar durante explosõesHuaman, Denis Pavel Cabezas 26 March 2015 (has links)
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Previous issue date: 2015-03-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The project aims to study the disturbances (responses) of the low solar atmosphere caused
by solar flares, using Hα, 30 THz (10 μm), UV/EUV, soft and hard X-rays observations,
and a wide range of radio waves emissions (microwaves, millimeter, sub-millimeter). This
set of multispectral data enabled us to (i) examine in detail various aspects of the phenomena,
(ii) determine the origin of the radio emission during the gradual phase, and
therefore (iii) understand the mechanism of the particles acceleration. The data we used
for the completion of this study are based on Hα and 30 THz (10 μm) observations, made
by the high cadence flare imaging system installed at OSM4 and CASLEO5 observatories,
additionally data from HASTA (H-Alpha Solar Telescope for Argentina) telescope
installed at OAFA6 observatory. In the sub-millimeter and millimeter domain at 212,
405 GHz and 45, 90 GHz, were from SST (Solar Sub-millimeter Telescope) and from POEMAS
(POlarization Emission of Millimeter Activity at the Sun) solar radio telescopes,
respectively. Complementary radio observations in the microwave range (0.2-15 GHz)
from RSTN (Radio Solar Telescope Network) were considered. In addition, solar observations
obtained by RHESSI (Reuven Ramaty High Energy Solar Spectroscopic Imager),
Fermi and GOES (Geostationary Operational Environmental Satellite) satellites in X-ray
channels, and from AIA (Atmospheric Imaging Assembly) and HMI (Helioseismic and
Magnetic Imager) instruments, onboard the SDO (Solar Dynamics Observatory) satellite,
respectively. / O trabalho tem como objetivo estudar as perturbações da baixa atmosfera solar produzidas
pelas explosões solares, usando observações em Hα, 30 THz (10 μm), UV/EUV, raios
X e uma ampla faixa de emissões em ondas de rádio (microondas, milimétrica, submilimétrica); com o propósito de determinar a natureza dos processos físicos envolvidos. Este conjunto de dados multiespectrais nos permitiu (i) analisar os diferentes aspectos das
explosões tanto na fase impulsiva como gradual, (ii) determinar a origem da emissão em
rádio durante a fase gradual, e consequentemente (iii) entender melhor os mecanismos
de aceleração das partículas. Os dados em Hα e 30 THz foram fornecidos pelo sistema
de aquisição de dados com alta resolução temporal, instalado nos observatórios OSM1
e CASLEO2, adicionalmente dados do telescópio HASTA (H-Alpha Solar Telescope for
Argentina) instalado no observatório OAFA3. Enquanto as observações em rádio, os dados
foram do rádio polarímetro POEMAS (POlarization Emission of Millimeter Activity
at the Sun) nas frequências de 45 e 90 GHz, do telescópio SST (Sub-millimeter Solar
Telescope) nas frequências 212 e 405 GHz, ambos instalados no CASLEO. Dados na
faixa de microondas (0,2-15 GHz) obtidos pela rede RSTN (Radio Solar Telescope Network).
Além disso, foram considerados observações do Sol obtidas pelos satélites RHESSI
(Reuven Ramaty High Energy Solar Spectroscopic Imager), Fermi e GOES (Geostationary
Operational Environmental Satellite) para raios X, e dos instrumentos AIA (Atmospheric
Imaging Assembly), HMI (Helioseismic and Magnetic Imager), a bordo do satélite SDO
(Solar Dynamics Observatory), respectivamente.
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