Abstract Seven geological sections have been examined and sampled with emphasis on sedimentological & diagenetic processes within Abu Ghaylan Formation and the contact relationships with the underlying Abu Shaybah and overlying Kiklah Formations. Based on current detailed field loggings and microscope investigations, 10 facies are recognized within Abu Ghaylan Formation. The lowermost succession characterised by an overall transition from continental fluvially dominated deposits of the Abu Shaybah Formation into transitional to marginal marine, tidal flat deposits of the Abu Ghaylan Formation upward. The transitional nature of this lowermost part succession is demonstrated by interbeddings of claystone, sandstone and fossiliferous facies arranging in coarsening up cycle, in which most probably deposited in estuary / beach environment.The Abu Ghaylan Formation generally wedges laterally eastward and exposes intermittently east of Wadi Ghan area resulting of syngenetic uplift of Wadi Ghan area followed by erosion (ElHinnawy & Cheshitev, 1975). A slightly earlier uplift and greater erosion in a westward sloping basin of deposition near the close of the Early Jurassic and Early Cretaceous times is suggested by Fatmi & Sbeta (1991). The current study reveals that several exposure surfaces are demonstrated within Abu Ghaylan Formation suggesting uplifting and erosion episodes interrupted Abu Ghaylan Formation, where a restricted distribution of Abu Ghaylan may suggest a local tectonic overprint.Although the overall impression is that the base beds of Kiklah Formation starts with sandstone and red clay beds as channel infill deposits above Abu Ghaylan carbonate unit with surface of unconformity, however, based on current close investigation, a sequence characterized by interbeddings of carbonate and greenish clay overlying Abu Ghaylan Formation with surface of unconformity and gradationally overlain by sandstone beds should be introduced as separate unit attributes to Kiklah Formation.The current study emphasizes and supports a solution collapse origin for the breccias and introduces better insight into architecture and geomorphology of the breccias bodies that are exposed in the area of study. The dissolution of evaporites is considered responsible for all breccias development in this stratigraphic interval. According to the occurrence mode of breccias, the breccias intervals have been divided into two main parts; a lower section of strata that contains collapsed paleocaves and an upper section of strata that is deformed to varying degrees due to the collapse and compaction of the section of paleocave-bearing strata. The sharp flat base, inverse grading, V-shaped/ sag structures and irregular undulating top of brecciated bodies are recognized within Abu Ghaylan Formation and typically characterize solution collapse processes. Based on field study and architecture relationships, five distinctive karst facies are recognized in the area of study.The early diagenetic genetically related processes probably interrupted the deposition of Abu Ghaylan Formation is a most possible assumption for the origin and timing of breccias formation.
أحمد أبوبكر الحلو (2015)

يتضمن هذا البحث دراسة نظرية لمنظومة إنتاج وتشغيل للطاقة بالاعتماد على الطاقة الشمسية لمنزل افتراضي يقع في الجنوب الليبي وبالتحديد في مدينة سبها التي تقع جغرافياً على خط طولشرقاً وعلى خط عرضشمالاً، حيث تمت دراسة المنظومة المزودة للطاقة الكهربية من الطاقة الشمسية وتقوم هذه المنظومة بتزويد المنزل باحتياجاته من الطاقة بشكل مستمر وآمن وكما قمت بدراسة المنظومة الحرارية وتوصلت من خلالها على الطاقة الحرارية اللازمة لتسخين المياه لجميع الاستخدامات المنزلية. وتهدف هذه الدراسة إلى توليد الطاقة الكهربية والتقليل من تكلفة الكهرباء، وإمداد المناطق النائية بما تحتاجه من طاقة كهربية، والحفاظ على البيئة، وحل لمشكلة انقطاع الكهرباء، ومن خلال برنامج pvsyst تحصلت على الطاقة المنتجة في اليوم من منظومة الخلايا الكهروضوئية وقد بلغت تقريباً 38.8 KWh/day،أما الطاقة المستخدمة لتشغيل الأحمال في المنزل لمدة سنة هي تقريباً14177 KWhواستخدم منها حوالي12204KWhأما بالنسبة للطاقة الناتجة من منظومة التحويل الحراري المباشر فبلغت حوالي 13.34 KWh/dayكما قمت بحساب القدرة التشغيلية للمنظومة الحرارية وبلغت 2.668kw/day وهذه القدرة تتغير يومياً وشهرياً وسنوياً، اما عند حسابي لتكلفة الطاقة الناتجة من منظومة التحويل الكهربائي فتحصلت على أن سعر الكيلو وات ساعة للطاقة المستخدمة هو0.21 L.D ، إما تكلفة التشغيل السنوية للمنظومة هي2540 دينار سنوياً، الطاقة للكهرباء التقليدية هي279.6 دينار سنوياً، حيث لاحظت من خلال المقارنة بين التكلفتين بأن سعر الكيلو وات ساعة الذي تحصلت عليه من المنظومة الشمسية الكهربائية أعلى من تكلفة الكهرباء التقليدية وهذا يرجع إلى أن التكلفة الإنشائية لهذه المنظومة لازالت مرتفعة، فهذا يدل على أن منظومات الطاقة الشمسية لا يمكنها المنافسة إلا عند تخفيض تكلفتها الانشائية وباستثناء المناطق البعيدة. Abstract This includes research study of the theory of system production and operation of energybased on solar energy to the home by default is located in the south of Libya, specifically in the city of Sabha , which is geographically situated on the longitude 27.02 east and latitude 14.34 north, where it was the study of the system equipped with electric power from solar energy and play this system provide home its energy needs on an ongoing basis and safe , as you study the system thermal and reached whereby theThermal energy needed to heat the water for all household uses. The aim of this study is to generate electricity and reduce the cost of electricity , and supply remote areas with the necessary electrical energy, and the environment, and solving the problem of power outages, and through the program pvsyst obtained the energy produced per day from the system PV cells has reached nearly 38.8 KWh / day, the energy used to run the loads in the house for a year is almost 14177 KWh and use of which about 12204 KWh as for the energy generated by the system thermal conversion direct totaled about 13.34 KWh / day as you calculates the operational capacity of the system thermal and reached 2.668 kw / day this ability to change daily and monthly and annually either when my account for the cost of energy generated by the system conversion electric Fathsalt that the price per kilowatt hour of energy used is 0.21 LD, either annual running cost of the system is 2540 dinars annually , either the energy cost of traditional electricity was 279.6 dinars per year, where I noticed through comparison between Altklfattan that the Price per kilowatt hour , which it obtained from the solar system electrical higher than the cost of conventional electricity and this is due to the cost of construction of such a system is still high ,. It shows that the solar energy systems can not compete only at reducing the cost of construction and with the exception of remote areas.
الزينة سليمان عمر موسي (2015)

Swirl stabilised combustion is one of the most successful technologies for flame stabilisation in gas turbine combustors. Lean premixed combustion systems allow the reduction of NOx coupled with fair flame stability. The swirl mechanism produces an aerodynamic region known as central recirculation zone (CRZ) providing a low velocity region where the flame speed matches the flow velocity, thus anchoring the flame whilst serving to recycle heat and active chemical species to the root of the former. Another beneficial feature of the CRZ is the enhancement of the mixing in and around this region. However, the mixing and stabilisation processes inside of this zone have shown to be extremely complex. The level of swirl, burner outlet configuration and combustor expansion are very important variables that define the features of the CRZ. The complex fluid dynamics and lean conditions pose a problem for stabilization of the flame. The problem is even more acute when alternative fuels are used for flexible operation. Therefore, in this paper swirling flame dynamics are investigated using computational fluid dynamics (CFD) with commercial software (ANSYS). A new generic swirl burner operated under lean-premixed conditions was modelled. A variety of nozzles were analysed using isothermal case to recognize the the behavers of swirl . The investigation was based on recognising the size and strength of the central recirculation zones. The dimensions and turbulence of the Central Recirculation Zone were measured and correlated to previous experiments. The results show how the strength and size of the recirculation zone are highly influenced by both the shear layer surrounding the Central Recirculation Zones (CRZ) and outlet configurations. arabic 11 English 64
Adel Diyaf, Hesham Baej, Adel Akair, Salem Adeilla, Abdurahman Kraiem(9-2018)