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The clinker cooling stage is one of the important stages in cement production processes due to the effect of this stage on the produced cement properties. This stage takes place in the clinker cooler which has many types, one of these types is the Grate Cooler.In this thesis the thermal performance of the cooler was studied by using a mathematical model. The clinker motion parameters, which were used in the heat transfer model, were considered according to the standard available by the manufacturing company.The solution of the system of equation are solved using a finite difference method. The clinker and the cooling air temperature profiles and the rate of heat transfer between the clinker and the cooling air along the cooler length are evaluated. The model has been employed to examine the effect of different variables on the temperature gradient for both the clinker and the cooling air.The variables include the residence time, the mass flow rate of the clinker, the mass flow rate of the air and blockage some not effected compartments. The model shows that changing of the above variables affect the temperature gradient of the clinker and the air along the cooler and so the value of the clinker temperature exit from the cooler.In addition to its effect on the heat exchange rate along the length of the cooler. The two-dimensional packed bed partial differential equations are found to have an acceptable accuracy to predict the behavior of the system.One of the important results of the study is the study is the effect of each compartment on the heat transfer process. It is found that, for the practical operating conditions, the maximum heat transfer occurs through the first three compartments of the cooler. The results indicate that the temperature profiles of the clinker bed have always an exponential type all over the axial direction.

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The centrifugal fan is the most widely used because it can efficiently move large quantity of the gas over a wide range of pressures. The flow that enters throughout the impeller is analyzed by using a streamline curvature technique, this method used for a compressor, by neglect the term of gas density change. The turbulent flow is modeled by using algebraic eddy viscous model which based on the mixing length, the turbulent model is applied on the hub to shroud stream surface. The shock in the present work is form by increasing the volume flow rate in put to the impeller. The impeller that chosen in this work is the impeller of the pre-heater fan in the heating system of clinker in AL-Muthanna factory of cement, which has back curved blade. The results prove that the increasing in the volume flow rate (forming shock losses) has an effect on the velocity profile and static pressure, so that where the volume flow rate increase the velocity profile increase and static pressure decrease

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High European energy demands, the difference in prices amongst Europe and ambitious gas producers, have produced a scenario of high competition in a region that suffers a lack of fossil resources still required for energy generation. Therefore, other sources are under the scope of various countries to mitigate these issues. Shale gas is one fuel that presents a scenario that would decrease European dependence on imported gas. Although shale gas production is unlikely to give the energy security desired to the whole Europe, it would make a difference for the communities that will adopt it. However, shale gas has acquired a bad reputation with the public, mainly because of its extraction methods. This bad reputation is attributed to hydraulic fracturing, technology well-known as fracking, and its risks associated towards air and water pollution. Therefore, companies, institutions and governments are looking for other alternative methods of extraction with more environmentally friendly processes. Producing extensive high-pressure pulse waves at the base of the wellbore by using detonation is a promising potential technique for shale gas extraction. A fundamental study of deflagration to detonation transition using recirculated shale gas formation with pure oxygen as an oxidiser has been studied to design a system with lower DDT distance and higher pressure waves. Three proposed cases of UK shale gas composition were studied. Chemical equilibrium software GASEQ and chemical kinetic software CHEMKIN-PRO were used to estimate the product parameters. Results showed that the effect produced by diluents, such as carbon dioxide, are eliminated by the use of higher hydrogen content carbon-to-hydrogen species for the three cases proposed. OpenFOAM CFD was used to calculate the deflagration to detonation transition parameters in stoichiometric hydrogen air mixtures to evaluate different obstacle geometries on the transition phenomenon to improve the detonation process. The shape and layout of obstacles were found to have a significant effect on flame acceleration, and subsequent detonation propagation. The interaction of transverse pressure waves generated at the obstructions governs the propagation mechanism. The transverse waves and its frequency appear to play a pivotal role in supporting the detonation wave. It was found that rectangular shape obstacles reduce the reaction time, while triangular ones achieved detonation with the minimum run-up distance. On the other hand, semi-circular shape obstacles generate the highest pressure in a detonation tube. The outcome from numerical calculations and CFD were the guide to construct an experimental rig of 21.2mm diameter and 1500mm length tube with different obstacle configurations to demonstrate the concept of pulse detonation for shale rock cracking. Experimental work has been performed to determine the potential of shale gas production in the Dullais Valley, South of Wales. It was found through several tests using BS standard volatile analyses, Transmission Electron Microscopy and pyrolysis RockEval evaluation that the potential of extraction in this region is fair, with similar concentrations of pyrite but with low energy content compared to those resources located in the Midlands and Yorkshire. However, the use of controlled pulse detonation could be the ideal technology for extraction in Wales, as low sulphur (S) content will produce lower unwanted emissions, with a process that can promote opening of pores and further gasification of oil based molecular, with a subsequent increase in shale gas production, topic that requires further research. Finally, a 2-dimensional simulation was performed using ANSYS Parameter Design Language (APDL) to investigate the effect of pressure pulse generated by the detonation tube on a pre-crack. Results showed that the layer close to the applied load will be displaced, which means that it will be smashed. The maximum Von Mises stresses were found to concentrate at the perforating hole corners, while the region immediately after the crack tip is susceptible to compression stresses. The Same behaviour was found for the stress intensity factor. According to that, it is believed that the cracks will propagate diagonally from the perforating hole base. Therefore, the current work has theoretically demonstrated the technology for shale gas recovery, with an optimised geometry consistent of internal obstacles, for a region with potential for shale gas exploitation.

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Shale gas presents an opportunity to alleviate European dependence on imported gas, which is required for load matching within future renewable energy systems. However, shale gas has acquired a negative public image primarily due to ‘hydraulic fracturing’ extraction methods, commonly known as ‘fracking’, whose risks include air and water pollution. Hence, there is the need to appraise alternative proposals for shale gas extraction where environmental risks are mitigated or negated. Producing high-pressure waves at the base of the wellbore by using small, control gaseous detonations offers promising potential for shale gas extraction, negating the primary risks associated with hydraulic fracturing. A fundamental study of deflagration to detonation transition using recirculated shale gas mixed with pure oxygen as an oxidiser has been undertaken within a programme to design a system with lower DDT distance and higher amplitude pressure waves. Three UK shale gas compositions were studied. The chemical equilibrium software GASEQ and chemical kinetic software CHEMKIN-PRO were used for simulation. Results show that the influence of diluents, such as carbon dioxide can be eliminated by the use of higher hydrogen-content species for the three cases proposed. OpenFOAM CFD was used to estimate the detonation-to-deflagration transition parameters in stoichiometric hydrogen/air mixtures to evaluate different obstacle geometries on the transition phenomenon. It was found that rectangular shape obstacles reduce the reaction time and hence decrease the run-up distance to achieve DDT whilst, semi-circular shaped obstacles generate the highest pressure in a detonation tube. The outcome from numerical predictions is guiding the construction of an experimental programme with different obstacle configurations to demonstrate the concept of consistent pulse detonation for shale-rock cracking.

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In gas turbine systems, operation stability represents the major challenge to any successful device deployment. Climate change combined with fossil fuel pollution has led to the need of considering high hydrogen content fuels, thus putting more pressure to stabilise gas turbines at operation conditions. Flashback is one of the main operation stability problems that represent a real challenge for gas turbine designers when using fast reacting fuels with high hydrogen content. One mechanism that has shown to contribute to flashback considerably is the propagation of the flame through its boundary layer. Although the latter has been studied, there are still several unknowns in its evolution through the system. Thus, boundary layer flashback of a swirling turbulent flame was investigated in a 150 kW tangential swirl burner previously characterised. To produce controlled changes to the boundary layer, the internal side of the burner was covered by woven wire steel mesh to mimic biological skin techniques in flow drag improvement. Two different wire meshes were used to study the effect of the regular roughness size on the boundary flashback. Moreover, the effects of using the wire mesh in such swirling flow with and without central air injection for reduction of other flashback phenomena were studied. The results show good enhancement of the system to boundary layer flashback, and a new map of the combustion stability of the rig has been produced.

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The preheater system is an imperative part of the dry cement production line. Besides its significant it represents the transition step from the wet to dry process for cement production. This paper studies the effect of calcinations degree occur in the preheater system and bypass of kiln gases on the heat content of the gases in the preheating system. It is found the heat content of gases is (542.035, 801.86, 1034.27 and 1192.7) kJ at 90% calcinations degree and 40% bypass of kiln gases, whereas it is(541.41, 801, 1033.2 and 1191.5) kJ at 50% calcinations degree and 40% bypass of kiln gases for Cyclones (I, II, III and IV) respectively. Also their effects on the heat content of bypass gases are presented and it is found that the calcinations degree has inversely effect with the heat content of bypass gases.

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In this investigation, study of a steady state tow-dimension free convection of non-Newtonian flow inside an different enclosures with laminar flow has been studied numerically. Two kinds of boundary conditions were considered , first when the inner holes were under constant heat flux and second when inner holes heat-ed to constant temperature while enclosure wall was insulated in all cases. Wide ranges of Rayleigh numbers(1.34E03, 1.34E04 and 1.34E05), power law index (0.1, 0.5,1 and 5) with Prandtl number(1.37, 6.37 and 15.37) are implemented.. The results pre-sented in terms of isotherms to present the temperature field. Be-sides that, the relationships between Nusselt number and other essential parameters such as, Rayleigh numbers, Prandtl number and power law index are exhibited. The results proved that Nusselt number strongly affect by all parameters mentioned pre-viously. The effect of alteration of power law index for non-Newtonian fluid on the temperature distribution was elucidated. Also, increasing of Prandtl number lead to increasing of Heat transfer rate for a given rest parameters, consequently.

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Pure water production is considered as an utmost necessity, especially in the arid and remote areas. One of the most important processes in this production is the distillation using an alternative source as a power supply. Recently, solar distillation systems were widely studied, mainly because of its low cost and ease of use. In the present study, the effect of air velocity and presence of wire screen mesh on a conventional single slop solar still performance were investigated experimentally. It is found that the solar still productivity can be improved by 22.8% with increasing of air velocity up to 4 m/s. Adding a wire screen mesh with increasing of air velocity, up to 2.5 m/s, resulted in an increase of the solar still productivity up to 36.6%.

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The fossil fuels used in internal combustion engines are among the largest contributors to environmental degradation, and this fuel has a high economic cost, so the need to use alternative fuels with less environmental impact and less cost-effective cost. Therefore, researchers resorted to using different kinds of alternative fuels, including liquefied petroleum gas. This study provides a practical study comparing the use of LPG and gasoline in terms of performance and emissions from the four-stroke spark ignition, single cylinder, air cooled with a constant pressure ratio and variable-speed 1500–2500 rpm. A difference in volume efficiency, the brake thermal efficiency, fuel consumption and emissions of gases (HC, NOx, CO2, CO) has been measured that results have shown improved fuel consumption and thermal efficiency when using LPG fuel compared to pure gasoline. In contrast, the volume efficiency showed negative results when using LPG. the results also showed an improvement in LPG emissions in HC, NOx, CO2, CO with the use of LPG.

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The natural heat transfer in ducts depend on generating an induced flow due to the difference in density between the heated fluid and it is environment. The effect of reduce cross sectional area of a vertical isothermal duct by adding half circular obstacles to the inner side of the duct. The effect of the induced flow and obstacles were study using COMSOL software and compared to heat through same duct with no flow. The results that obstacles increase induced flow by 16% compared to normal vertical duct, Also shows a reduction in value of the maximum temperature of the hot surface at the solar peak heat flux (3:00 PM).