Compositional Changes in Athabasca Bitumen During Air Injection into Mature SAGD Chambers - Observations from 3-D Large Scale Experiments

2020 ◽  
Author(s):  
Belenitza M. Sequera-Dalton ◽  
Ehsan Aminfar ◽  
Robert G. Moore ◽  
Sudarshan A. Raj Mehta ◽  
Matthew G. Ursenbach
Keyword(s):  
Large Scale ◽  
Air Injection ◽  
Athabasca Bitumen ◽  
Compositional Changes

An Approach for Efficient CFD Simulations of an Ejector Air Injection System for Active Aerodynamic Compressor Stabilization

2017 ◽  
Author(s):  
Sebastian Brehm ◽  
Felix Kern ◽  
Jonas Raub ◽  
Reinhard Niehuis
Keyword(s):  
Large Scale ◽  
Armed Forces ◽  
Air Injection ◽  
Injection System ◽  
Cfd Simulations ◽  
Data Set ◽  
Numerical Effort ◽  
Enhance Efficiency ◽  
Set Up ◽  
Novel Concept

The Institute of Jet Propulsion at the University of the German Federal Armed Forces Munich has developed and patented a novel concept of air injection systems for active aerodynamic stabilization of turbo compressors. This so-called Ejector Injection System (EIS) utilizes the ejector effect to enhance efficiency and impact of the aerodynamic stabilization of the Larzac 04 two-spool turbofan engine’s LPC. The EIS design manufactured recently has been subject to CFD and experimental pre-investigations in which the expected ejector effect performance has been proven and the CFD set-up has been validated. Subsequently, optimization of the EIS ejector geometry comes into focus in order to enhance its performance. In this context, CFD parameter studies on the influence of in total 16 geometric and several aerodynamic parameters on the ejector effect are required. However, the existing and validated CFD set-up of the EIS comprises not only the mainly axisymmetric ejector geometry but also the highly complex 3D supply components upstream of the ejector geometry. This is hindering large scale CFD parameter studies due to the numerical effort required for these full 3D CFD simulations. Therefore, an approach to exploit the overall axissymmetry of the ejector geometry is presented within this paper which reduces the numerical effort required for CFD simulations of the EIS by more than 90%. This approach is verified by means of both experimental results as well as CFD predictions of the full 3D set-up. The comprehensive verification data set contains wall pressure distributions and the mass flow rates involved at various Aerodynamic Operating Points (AOP). Furthermore, limitations of the approach are revealed concerning its suitability e.g. to judge the response of the attached compressor of future EIS designs concerning aerodynamic stability or cyclic loading.

Reverse Engineering Earthquakes using Lab-scale Replicas: Application to Mw5.5 2017 Pohang Earthquake

2020 ◽  
Author(s):  
Antoine L. Turquet ◽  
Renaud Toussaint ◽  
Fredrik K. Eriksen ◽  
Eirik Grude Flekkøy ◽  
Knut Jørgen Måløy
Keyword(s):  
Porous Medium ◽  
Large Scale ◽  
Sampling Rate ◽  
Gas Injection ◽  
Air Injection ◽  
Image Correlation ◽  
Different Types ◽  
Seismic Location ◽  
Analogous Model ◽  
Event Times

<p>An earthquake can happen due to many different phenomena such as sliding faults, fluid/gas injection into the subsurface or volcanic activities. Understanding the cause of earthquakes is one important step towards a better hazard assessment and better mitigation. In this study, we explore the physics behind different types of earthquakes by inducing similar mechanics in lab-scale experiments using an analogous model. Inside a transparent rectangular Hele-Shaw cell, we induce lab-scale microseismicity via pneumatic fracturing. An 80 x 40 cm transparent setup is prepared using a 1 mm thin layer of uncompacted granular medium having a fixed grain size is placed between two glass plates.<br>The seismic location results are compared with the image correlation results for displacement maps corresponding to the event times. Using air injection, this porous medium is compacted and fractured. This system is monitored using a camera recording 1000 images per second and accelerometers recording with 1 MHz sampling rate. Sources of earthquake-like vibrations are both located using acoustic recordings and image processing. We have observed that the deformation starts with compaction inside the medium; this compaction propagates toward the channel tips and causes the fingers to advance further inside the medium. We have observed (using optics and acoustics) that the movement starts inside the porous medium and progresses toward the channel tips, eventually causing channels to grow further. We also compared the characteristic patterns in these lab-scale events that are very similar to large scale correspondents, in particular with 2017 Mw 5.5 Pohang Earthquake. We reverse-engineered the signature of the recorded lab-scale signals to have a better understanding of this industrial hazard.</p>

Evaluation of Air Injection into Mature SAGD Chambers as a Follow Up/Wind-Down Strategy, Using a Novel Large Scale 3-D Physical Model

2019 ◽  
Author(s):  
Ehsan Aminfar ◽  
Belenitza Sequera-Dalton ◽  
Sudarshan Raj Mehta ◽  
Gordon Moore ◽  
Matthew Ursenbach
Keyword(s):  
Physical Model ◽  
Large Scale ◽  
Air Injection

Morphological Transformations of Top Electrodes on YMnO3 Caused by Filamentary Resistive Switching in the Oxide Matrix

2015 ◽  
Vol 1101 ◽  
pp. 120-123 ◽  
Author(s):  
Agnieszka Bogusz ◽  
Daniel Blaschke ◽  
Danilo Bürger ◽  
Oliver G. Schmidt ◽  
Heidemarie Schmidt
Keyword(s):  
Resistive Switching ◽  
Large Scale ◽  
Adverse Impact ◽  
Small Scale ◽  
Voltage Sweep ◽  
Current Voltage ◽  
Compositional Changes ◽  
Oxide Matrix ◽  
Morphological Transformations ◽  
Unipolar Resistive Switching

Unipolar resistive switching in YMnO3with large-scale bottom and small-scale top electrodes is analyzed in detail by tracking the morphological transformations of the top electrodes induced by applied writing voltages. Micro-scale digital images are taken after each subsequent quasi-static current-voltage sweep. Current mapping after electrical investigations indicates a shift in the conductivity at the localized areas of the morphologically transformed top electrodes. Those changes are assigned to the heat induced structural and compositional changes within YMnO3which lead to the formation and rupture of conductive filaments observed as unipolar resistive switching. Presented results underline the importance of Joule heating in the fostering of resistive switching and its adverse impact on the device endurance.

Compositional Changes for Athabasca Bitumen in the Presence of Oxygen Under Low Temperature Conditions

2004 ◽  
Author(s):  
N. Jia ◽  
R.G. Moore ◽  
S.A. Mehta ◽  
K. Van Fraassen ◽  
M. Ursenbach ◽  
...  
Keyword(s):  
Low Temperature ◽  
Athabasca Bitumen ◽  
Temperature Conditions ◽  
Compositional Changes

An investigation of factors influencing nutrient loss from absorbent materials during ensiling

1991 ◽  
Vol 1991 ◽  
pp. 93-93 ◽  
Author(s):  
C P Ferris ◽  
C S Mayne
Keyword(s):  
Chemical Composition ◽  
Dairy Cow ◽  
Large Scale ◽  
Nutrient Loss ◽  
Nutrient Recovery ◽  
Factors Influencing ◽  
Silage Fermentation ◽  
Production Study ◽  
Beet Pulp ◽  
Compositional Changes

Including dry feed materials (absorbents) with grass at ensiling has been shown to reduce effluent output and improve silage fermentation (Offer and Al-Rwidah, 1989) although the effects of this practice on animal performance have been somewhat variable (Ferris and Mayne, 1990; Jones, Jones and Moseley, 1990). However little is known about the fate of these absorbents during ensilage or the effects of ensiling upon their chemical composition. The aim of this investigation, which was part of a large scale dairy cow production study was to examine the nutrient recovery and compositional changes occurring with unmolassed sugar-beet pulp (SBP) when ensiled with grass at three levels of inclusion.

A Large Scale Turbine Test Rig for the Investigation of High Pressure Turbine Aerodynamics and Heat Transfer With Variable Inflow Conditions

2015 ◽  
Author(s):  
Alexander Krichbaum ◽  
Holger Werschnik ◽  
Manuel Wilhelm ◽  
Heinz-Peter Schiffer ◽  
Knut Lehmann
Keyword(s):  
Heat Transfer ◽  
High Pressure ◽  
Large Scale ◽  
Measurement Techniques ◽  
Air Injection ◽  
Test Rig ◽  
High Pressure Turbine ◽  
Film Cooling Effectiveness ◽  
Cooling Air ◽  
Inflow Conditions

Focusing on the experimental analysis of the effect of variable inlet flows on aerodynamics, efficiency and heat transfer of a modern high pressure turbine, the Large Scale Turbine Rig (LSTR) at Technische Universität Darmstadt has been extensively redesigned. The LSTR is a full annular, rotating low speed turbine test rig carrying a scaled 1.5-stage (NGV1 - Rotor - NGV2) axial high-pressure turbine geometry designed by Rolls-Royce Deutschland to match engine-realistic Reynolds numbers. To simulate real turbine inflow conditions, the LSTR is equipped with a combustor simulator module including exchangeable swirlers. Other inflow conditions include axial or turbulent inflow as well as altered relative positions of swirl cores and NGVs by traversing. To investigate combustor-turbine interaction, the LSTR offers a large variety of optical and physical access ports as well as high flexibility to the application of measurement techniques. An elaborate secondary air system enables the simulation of various cooling air flows. The turbine section is equipped with film-cooled NGVs, a hub side seal air injection between NGVs and rotor, as well as a hub side RIDN cooling air injection module designed to provide realistic turbine flow conditions. Exchangeable hub side RIDN-plates allow for investigation of different coolant injection geometries. Measurement capabilities include 5-hole-probes, Pitot and total temperature rakes, as well as static pressure taps distributed along NGV radial sections and at the hub side passage endwall. The NGV passage flow can be visualized by means of Particle Image Velocimetry (PIV). Hot Wire Anemometry (HWA) will be used for time-resolved measurements of the turbulence level at several positions. The distributions of heat transfer and film cooling effectiveness are acquired using infrared thermography and CO2-gas tracing.

Prediction of flow rates and stability in large scale airlift reactors

1996 ◽  
Vol 34 (5-6) ◽  
pp. 51-57 ◽  
Author(s):  
John W. Hinks ◽  
Howard Cawte ◽  
David A. Sanders ◽  
Adam Hudson ◽  
Christopher N. Dockree
Keyword(s):  
Large Scale ◽  
Injection Rate ◽  
Air Injection ◽  
Stable Operation ◽  
Two Phase ◽  
Nineteen Seventies ◽  
Effluent Quality ◽  
Airlift Reactors ◽  
Injection Rates

Large-scale High Recirculation Airlift Reactors have been used to treat biodegradable waste waters since the mid nineteen seventies. The system is particularly attractive for situations where the land to locate wastewater works is restricted. Little is known, however, about the fluid dynamics of the gas-liquid mixture flowing around the reactor. This makes the determination of air injection rates difficult if effluent quality and dynamic stability are to be maintained. When the air injected is not sufficient to maintain stable operation the reactor contents may reverse violently resulting in down time, failure to achieve target discharge quality and possible damage to the reactor itself. As a result many reactor installations operate at air injection rates above those necessary for the biological processes. The extra air injected results in higher capital and process costs. This paper considers the effect of air injection rates on the hydrodynamic stability of Airlift Reactors and a two-phase model is proposed to predict stable operation at a reduced air injection rate. Results are presented which show the effect of reactor design on stability.

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