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    The impact of wettability and fluid saturations on multiphase representative elementary volume estimations of micro-porous media

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    The occurrence of multi-phase flows in porous media is a complex phenomenon that involves multiple scales, ranging from individual pores to larger continuum scales. Upscaling frameworks have emerged as a response to the need for addressing the disparity between micro-scale processes and macroscopic modelling. Determination of the representative elementary volume is important for understanding fluid dynamics in micro-porous materials. The size of the representative elementary volume for multiphase flow in porous media is significantly affected by wettability and fluid saturations. Previous studies have overlooked this aspect by conducting simulations under conditions of constant medium wettability and fluid saturations. This study uses finite volume simulations with a volume of fluid approach for two distinct asymptotic homogenization methods, namely hydrodynamic bounds of relative permeability and thermodynamic bounds of entropy production. Strong wetting conditions with high wetting phase saturation were found to require a smaller sample size to establish representative elementary volume, while mixed-wettability scenarios necessitate the largest sample sizes. These findings improve our understanding of multiphase fluid flow behaviour in micro-porous materials and aid in enhancing techniques for scaling up observations and predictive modelling in engineering and environmental fields.Document Type: Short communicationCited as: Hussain, S. T., Regenauer-Lieb, K., Zhuravljov, A., Hussain, F., Rahman, S. S. The impact of wettability and fluid saturations on multiphase representative elementary volume estimations of micro-porous media. Capillarity, 2023, 9(1): 1-8. https://doi.org/10.46690/capi.2023.10.0

    Microbial production of hydrogen under mesophilic conditions.

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    Fermentative hydrogen production from biomass using mixed anaerobic cultures has a greater potential to be developed as a practical biohydrogen system than systems utilizing pure cultures. To optimize hydrogen production, it is important to inhibit hydrogen consumers during glucose fermentation. Long chain fatty acids (LCFAs) are inhibitors of aceticlastic methanogenic bacteria and these fatty acids could act as hydrogenotroph methanogenic inhibitor in fermentative hydrogen production. Batch studies were conducted to assess the effects of two C18 LCFAs on microbial hydrogen production from glucose under mesophilic conditions. Experiments were conducted using different concentrations of linoleic acid (LA) and oleic acid (OA) at 37+/-1°C. The effects of initial pH in the presence of two C18 LCFAs on hydrogen production were assessed by controlling the initial pH. Glucose was re-injected on day 4 or day 5 to examine the combined effect of LCFA and volatile fatty acids (VFAs) on hydrogen production and also the inhibition time dependence. (Abstract shortened by UMI.)Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .C46. Source: Masters Abstracts International, Volume: 44-03, page: 1471. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005

    Genetical stability and osteogenic ability of mesenchimal stem cells on demineralized bone matrices

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    Journal of Osseointegration Volume 7, Issue 1, 1 March 2015, Pages 2-7 Open Access Genetical stability and osteogenic ability of mesenchimal stem cells on demineralized bone matrices (Article) Pozzuoli, A.a, Gardin, C.b, Aldegheri, R.a, Bressan, E.c, Isola, M.d, Calvo-Guirado, J.L.e, Biz, C.a, Arrigoni, P.a, Feroni, L.b, Zavan, B.b a Department of Surgical,Oncological and Gastroenterological Sciences, University of Padua, Padua, Italy b Department of Biomedical Sciences, University of Padua, Padua, Italy c Department of Neurosciences, University of Padua, Padua, Italy d Department of Animal Medicine, Production and Health (MAPS), Italy e Department of General Dentistry, Faculty of Medicine and Dentistry, University of Murcia, Murcia, Spain Hide additional affiliations View references (44) Abstract Aim: Tissue engineering is a rapidly expanding field with regard to the use of biomaterials and stem cells in the orthopedic surgery. Many experimental studies have been done to understand the best characteristics of cells, materials and laboratory methods for safe clinical applications. The aim of this study was to compare the ability of 2 different human demineralized bone matrices (DBMs), the one enriched and the other not enriched with hyaluronic acid, to stimulate in vitro the proliferation and the osteogenic differentiation of human adipose-derived stem cells (ADSCs) seeded onto an osteoconductive scaffold. Materials and Methods: ADSCs were isolated, by enzymatic digestion, from abdominal adipose tissue of 5 patients undergoing cosmetic lipoaspiration surgery. ADSCs were then seeded onto a 3D scaffold in the presence of the two different osteoinductive matrices of human demineralized bone and evaluated for proliferation and osteogenic differentiation. The safety of the methods was verified using array-Comparative Genomic Hybridization (array-CGH). Results: ADSCs were able to differentiate in osteogenic sense. Both DBMs showed the ability to induce osteogenic differentiation of the cells. Conclusion: array-CGH showed no changes at genome level, thus confirming the safety of materials and method

    Skenario Pengembangan Untuk Meningkatkan Recovery Factor Pada Lapangan TR Lapisan X Dengan Menggunakan Simulasi Reservoir

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    Reservoir simulation is an area of reservoir engineering in which computer models are used to predict the flow of fluids through porous media. Reservoir simulation process starts with several steps; data preparation, model and grid construction, initialization, history matching and prediction. Initialization process is done for matching OOIP or total initial hydrocarbon which fill reservoir with hydrocarbon control volume with volumetric method.To aim the best encouraging optimum data, these development scenarios of TR Field Layer X will be predicted for 30 years (from 2014 until January 2044). Development scenarios in this study consist of 4 scenarios : Scenario 1 (Base Case), Scenario 2 (Base Case + Reopening non-active wells), Scenario 3 (scenario 2 + infill production wells), Scenario 4 (Scenario 2 + 5 spot pattern of infill injection wells)

    Skenario Pengembangan Untuk Meningkatkan Recovery Factor Pada Lapangan TR Lapisan X Dengan Menggunakan Simulasi Reservoir

    Full text link
    Reservoir simulation is an area of reservoir engineering in which computer models are used to predict the flow of fluids through porous media. Reservoir simulation process starts with several steps; data preparation, model and grid construction, initialization, history matching and prediction. Initialization process is done for matching OOIP or total initial hydrocarbon which fill reservoir with hydrocarbon control volume with volumetric method.To aim the best encouraging optimum data, these development scenarios of TR Field Layer X will be predicted for 30 years (from 2014 until January 2044). Development scenarios in this study consist of 4 scenarios : Scenario 1 (Base Case), Scenario 2 (Base Case + Reopening non-active wells), Scenario 3 (scenario 2 + infill production wells), Scenario 4 (Scenario 2 + 5 spot pattern of infill injection wells)

    Implementation of a recirculating TFF N-1 perfusion system at manufacturing scale: Conquering process hurdles and scaling challenges

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    In order to increase the output of a traditional large scale stainless steel fed-batch manufacturing facility without major engineering work, we investigated the implementation of N-1 perfusion technology to feed a more intensified fed-batch production process. Perfusion N-1 enables cells to grow to high densities in the seed train bioreactor. By shifting cell growth from production to seed train, we can increase seed train occupancy per batch and reduce production bioreactor occupancy per batch, which improves facility throughput by bringing the run duration ratio of N-1/N closer to unity. Instead of using the popular ATF technology, an in-house TFF system was developed to provide more flexibility during process development and optimization of all perfusion parameters. We will share a case study of how two different filtration technologies (open channel and hollow fiber) were developed and scaled from pilot scale to manufacturing scale while maintaining consistent cell growth performance at high cell densities, \u3e40x106 vc/mL. We will discuss the comparison of the two filter technologies, recirculation pump type selection, recirculation flow path design, filter area, skid/bioreactor design, and perfusion media volume challenges. Additional efforts were made in regards to SIP and sterility of these systems at pilot and manufacturing scale to safeguard the system from any potential contamination events. Sparger optimization work was also performed to solve mass transfer and cell damage challenges at pilot and manufacturing scales. Last but not least, a story of developing a scale-down model using peristaltic pump will be shared. Our work culminated in an engineering run at 17,000-L manufacturing scale using both technologies, which generated a high volumetric productivity of 750 mg/L/day and resulted in a 40% increase in facility output
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