Effect of Atmospheric Ice Accretion on the Dynamic Performance of Wind Turbine Blades

Atmospheric icing presents serious challenges to the development of wind power of the wind energy industry in cold regions. The potential detrimental impact on the safe operation of wind turbines and the energy harvest hasn’t been fully understood and requires further investigation. This thesis presents the research on icing profiles under different weather conditions and their impact on natural frequency, fatigue life, and lift and drag of the wind turbine blade. The research aims to develop a further understanding of the effect of atmospheric ice accretion on the structural integrity and aerodynamic performance of wind turbine blades through numerical and aerodynamic investigations to address the challenges facing the industry. A 5-MW NREL (National Renewable Energy Laboratory) wind turbine blade was selected for this study, due to availability of required geometric design parameters and experimental data for verification. The turbine rotor and its three blades were modelled and numerically simulated with commercial finite element software ANSYS. Three icing scenarios were chosen according to the ISO Standard and the corresponding icing profiles were developed to investigate their influence on vibrational behaviours of the wind turbine blade and rotor under different weather conditions. Icing loads were applied on the leading edge of the blade and natural frequency results were compared between clean and iced blades. It was found that harsh icing weather drove the natural frequency down to the near resonance limit, which could lead to significant issue on structural integrity of the wind turbine. The effect of atmospheric ice accretion with additional load due to varying wind speeds on the fatigue life of the wind turbine blade has been investigated. Significant reduction of fatigue life was found due to the increase of the von Mises stresses. Finally, computational fluid dynamics (CFD) analysis was carried out to investigate the effect of atmospheric ice accretion on the aerodynamic performance of typical 1-MW and 5-MW wind turbine blades. Results of the drag and lift coefficients and power production under different icing scenarios were obtained for five angles of attack. Compared with the results of the clean aerofoil profile, remarkable reduction in the power generation was observed due to the accreted ice at various aerofoil sections in the spanwise direction of the blade, demonstrating the detrimental impact of atmospheric icing on energy harvest for the wind energy industry

Quality of life among asthmatic children in Zagazig University Hospitals

Background: Asthma is a heterogeneous disease, usually characterized by chronic airway inflammation. The Pediatric Asthma Quality of Life Questionnaire (PAQLQ) is one of the most widely used instruments for measuring health-related QOL in children with asthma.Objective: to evaluate health-related quality of life (HRQOL) in children with bronchial asthma to identify the most important determinants adversely affecting their QOL.Patients and methods: This study was conducted on 72 asthmatic children over six months period. They were recruited from The Outpatient Clinic of Pediatrics Pulmonology Unit, Zagazig University Hospitals. All study patients were subjected to complete history taking, clinical examination, determination of level of asthma symptom control and filling PAQLQ.Results: About 58% of patients had partially controlled asthma and one quarter of them had well controlled asthma (Symptoms domain was the most affected domain ranged from 3 to 5.2 with mean 4.056). There was statistically significant relation between sex and physical, emotional and overall score of PQLQ. There was statistically significant relation between residence & social class and QOL scores. There was statistically significant relation between BMI and QOL scoresConclusion: Asthma significantly adversely affects the QOL of the affected children. Control of the main determinants of QOL scores might improve the QOL of these patients

Hydrophobic Polymers Flooding

Crude oil and other petroleum products are crucial to the global economy today due to increasing energy demand approximately (~1.5%) per year and significant oil remaining after primary and secondary oil recovery (~45-55% of original oil in place, OOIP), which accelerates the development of enhanced oil recovery (EOR) technologies. Polymer flooding through hydrophobically associated polyacrylamides (HAPAM) is a widely implemented EOR-technique, so they attracted much attention on both academic and industrial scales. Hydrophobically associating polyacrylamide (HAPAM) prepared by free radical emulsion polymerization of acrylamide (AM) monomer, divinyl sulfone as hydrophobic crosslinked moiety and surfmers, to chemically anchor a surfmer and hydrophobic crosslinker moiety onto the back bone of acrylamide chain. After that, polymeric nanocomposite was prepared through copolymerization of prepared HAPAM with different molar ratios of silica nanoparticles through one shot synthesis. Rheological properties for the prepared composites were evaluated. Wettability evaluation carried through quantitative and qualitative techniques where the results indicate novel polymers ability to alter rock wettability from oil-wet to water- wet

Review of synthesis, characteristics and technical challenges of biodiesel based drilling fluids

Acknowledgements The Egyptian authors were supported by Science, Technology & Innovation Funding Authority (STDF) under the grant (30894). The UK's authors would like to acknowledge the financial support from an Institutional Links grant, ID 352343681, under the Newton-Mosharafa Fund partnership. The grant is funded by the UK Department for Business, Energy and Industrial Strategy and delivered by the British Council. We are also grateful to the publishers, journals, and authors who provided their permission for us to reproduce their figures and tables in this review.Peer reviewedPostprin

Improvement of Heavy Oil Recovery by Nonionic Surfactant/Alcohol Flooding in Light of the Alkane Carbon Number and Interfacial Tension Properties

ACKNOWLEDGMENTS The Egyptian authors were supported by the Science, Technology & Innovation Funding Authority (STDF) under grant 30894. The authors from the UK would like to acknowledge the financial support from an Institutional Links grant, ID 352343681, under the Newton-Mosharafa Fund partnership. The grant is funded by the UK Department for Business, Energy and Industrial Strategy and delivered by the British Council. The authors would like to thank the EPRIEOR unit and staff as the surface and interfacial tension and contact angle measurements and chemical flooding tests were conducted at the EPRI-EOR unit.Peer reviewedPublisher PD

Developing a Thermally Stable Ester-Based Drilling Fluid for Offshore Drilling Operations by Using Aluminum Oxide Nanorods

Funding: This work was supported by an Institutional Links grant, ID 352343681, under the Newton–Mosharafa Fund partnership. The grant is funded by the UK Department for Business, Energy and Industrial Strategy, and Science, Technology & Innovation Funding Authority (STDF) and delivered by the British Council. For further information, please visit www.newtonfund.ac.uk. Science, Technology & Innovation Funding Authority (STDF) support was under the grant No. (30894). Acknowledgments: The authors would like to acknowledge the School of Engineering at the University of Aberdeen for providing the required facilities to complete this research. In addition, the authors would like to thank the support from MI-SWACO in providing commercial emulsifiers and consumables used in this project.Peer reviewedPublisher PD

Implantų pasekmės pacientams kurie yra susidūrę su periodontologine liga.

Objective: The aim of this systematic review was to assess the survival rate of dental implants placed in patients that have a history of treated periodontal disease and to further evaluate whether a history of periodontal disease increases the risk of having complications after implant placement, such as peri-implant diseases. Materials and Methods: Electronic databases were used to search (PubMed, Cochrane, Science Direct) and to identify articles concerning dental implant placement in patients with previous periodontal disease. After selection of the studies, 8 studies were included in this systematic review. The search of articles on the electronic databases was restricted to articles in the English language and articles published in the last 10 years (January 2010 to February 2020). Results: The results of studies reviewed in this thesis showed that is no negative effect on the survival of dental implants, however they did show a higher risk of peri-implant diseases in patients with a history of periodontal disease compared to patients without a history of periodontal disease. Conclusion: Regardless of the limitations of the systematic review, there is no substantial evidence that a history of periodontal disease may be a risk factor for dental implant failure, however a number of studies showed that there is a correlation between a history of periodontal disease and peri-implant disease. Further research and studies are needed to be able to establish whether or not a history of periodontal disease negatively affects the outcome of the placement of dental implants

Simulation for estimation of hydrogen sulfide scavenger injection dose rate for treatment of crude oil

The presence of hydrogen sulfide in the hydrocarbon fluids is a well known problem in many oil and gas fields. Hydrogen sulfide is an undesirable contaminant which presents many environmental and safety hazards. It is corrosive, malodorous, and toxic. Accordingly, a need has been long left in the industry to develop a process which can successfully remove hydrogen sulfide from the hydrocarbons or at least reduce its level during the production, storage or processing to a level that satisfies safety and product specification requirements. The common method used to remove or reduce the concentration of hydrogen sulfide in the hydrocarbon production fluids is to inject the hydrogen sulfide scavenger into the hydrocarbon stream. One of the chemicals produced by the Egyptian Petroleum Research Institute (EPRI) is EPRI H2S scavenger. It is used in some of the Egyptian petroleum producing companies. The injection dose rate of H2S scavenger is usually determined by experimental lab tests and field trials. In this work, this injection dose rate is mathematically estimated by modeling and simulation of an oil producing field belonging to Petrobel Company in Egypt which uses EPRI H2S scavenger. Comparison between the calculated and practical values of injection dose rate emphasizes the real ability of the proposed equation