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Item A STUDY OF THE EFFECT OF DEGRADATION ON INDUSTRIAL GAS TURBINE PERFORMANCE(Journal of Science, Technology, Mathematics and Education (JOSTMED), FUT Minna, 2016-03-15) Nasir, .A.; Usman, .S. A.; Mohammed, .A.; Muhammed, .S. N.; Bori IgeComponent degradation is a very common problem associated with operating industrial gas turbines. The major components so affected by this phenomenon are compressor, combustor and turbine blades. This paper studied the effect of degradation on gas turbine performance. The study involved the analyses of operating parameters effects for Siemens gas turbine engines model SGT5 – 2000E coded GT11 and GT21 in the power stations at Geregu power stations. The parameters considered were ambient temperature, exhaust temperature, combustion chamber pressure and turbine entry temperature, GT11 is degraded while GT21 is newly installed engine both in the same location at Geregu I and II power stations in Ajaokuta, Kogi State in the North central part of Nigeria.Simulations were carried out using Gas turb 11 simulation software, results of engine performance parameters were compared and it was revealed that due to component degradation, the turbine entry temperature (TET) increased to 1049.67oC, the fuel flow increased by 8.49% and power fell by 7.14%. Consequently, the cost of power loss is one hundred and eighty-seven million, one hundred and eleven thousand, seven hundred and fifty-three naira ninety-two kobo (₦187,111,753.92k) over a period of one year for the degraded gas turbine.Item ENERGY UTILIZATION, CONSERVATION AND AUDITING IN NIGERIA CEMENT INDUSTRY(Journal of Science, Technology, Mathematics and Education (JOSTMED), FUT Minna, 2016-03-15) Nasir, .A.; Bori Ige; Enitilo, .T.; Azeez, .O. S.; Muhammed, .A.Manufacturing of cement is identified as one of the most energy intensive industries in the world. Therefore, there is a need for its effective and efficient utilization and hence conservation. In order to produce clinker, rotary kilns are widely used in cement plants. This study takes a look at the energy source, utilization and conservation in a Cement Company in Nigeria. The company’s energy source was determined, utilization pattern investigated and possible areas of energy conservation considered. The rotary kiln of this plant where the large form of energy is consumed has a capacity of 6000 tonnes per day. It was found that about 20% of the total input energy was being lost through hot flue gas (5.09%), cooler stack (12.4%) and kiln shell (2.61% convection and radiation). To recover some of this heat energy loses, a feasible energy management method was introduced and discussed. Findings showed that approximately 4MW of electrical power could be recovered through conservation and proper energy management.Item DESIGN AND CONSTRUCTION OF A SMALL SOLAR POWERED AIR BLOWER FOR CHARCOAL FIRED FURNACE(JOURNAL OF THE NIGERIAN INSTITUTION OF MECHANICAL ENGINEERS, 2019-09-30) Muhammad, .A. B.; Nasir, .A.; Ayo, .S. A.; Bori IgeIn Nigeria almost all the local foundry shops rely on the manually operated blowers for supplying air for the combustion of the charcoals to melt metals. This manually operated blower has showed that much man-hour is required during firing as one laborer is dedicated to driving the rotary blower. This is labourous and reduces the rate of productivity of the enterprise. Therefore, it is necessary to find easier ways of supplying the energy required for the combustion so as to increase productivity. A solar powered blower is designed and constructed in this work. The performances of manually operated and solar powered air blowers are compared. Performance results of the manually operated air blower showed that it takes about 67 minutes and 42 minutes to melt 4kg of aluminum and zinc respectively. On the other hand, for the solar-powered air blower, it takes about 30 minutes and 17 minutes to melt 4kg of aluminum and zinc respectively. This indicates that the solar-powered air blower takes a shorter time to melt metals when compared with the manually operated air blower. In addition, the solar powered air blower eliminates the laborious aspect of supplying energy for melting metals and also reduces the times spent in metal melting process.Item INVESTIGATION OF PRESSURE TRANSIENTS AND WAVE PROPAGATION EFFECTS IN A PRESSURIZED PETROLEUM PIPELINE USING WANDA TRANSIENT SOFTWARE(Nigeria Journal of Engineering Science and Technology Research (FUT Yola), 2019-05-04) Muhammad, .A. B.; Nasir, .A.; Ayo, .S. A.; Bori IgePressure transients and effects of wave propagations due to instantaneous valve closure in a pipeline transporting premium motor spirit (PMS) were investigated using simulation approach in this paper. Pressure transient investigation and analysis are often more significant than the steady state analysis that hydraulic Engineers usually use in pipeline design because almost all pipelines experience pressure transient in their operations. Pressure transient analysis helps to understand the additional loads a pipeline can be subjected to as a result of instantaneous valve closures. In this paper, WANDA Transient 4.5.1210 commercial software was used for the analysis of the pressure transients due to instant valve closure in a petroleum pipeline. Three different instantaneous valve closure times of 4.5, 9 and 18 seconds were used in this investigation. It was observed in this research that rise in pressure is highest (1304 kPa) at node F (the node where the valve closure takes place) against the inlet pressure of 120 kPa and also there is drastic drop in pressure (-53.7 kPa) at node B (a node just upstream end of the pump). Also cavitations were observed at Node B due to the development of negative pressure as a result of the valve closure. The research recommends that surge tank should be installed at node F to stabilize the pressure surge and also air vessels are to be installed at node B to curtail damages due to cavitations.Item HEAT TRANSFER IN COOLED AERO-DERIVATIVE TURBINE BLADE: A NUMERICAL ANALYSIS(Journal of NIMechE, 2019-03-15) Orah, A. .M.; Nasir, .A.; Hassan, .A. B.; Bori IgeAero-derivative gas turbines have found extensive applications as mechanical drives and in medium-sized utility power plants. It has a higher efficiency due to its high pressure and temperature operations; hence, the need for proper cooling techniques to achieve the required creep life and attain reliability. In this paper, the heat transfer in a cooled aero-derivative gas turbine blade is determined numerically using the Alternating Direction Implicit (ADI) scheme of Computational Fluid Dynamics. The convective heat transfer coefficient of the governing Newton’s law of cooling equation is the basis. A solver was developed for the heat transfer problem based on the selected boundary conditions and designed cooling parameters of the GE PGT25+ aero-derivative gas turbine to obtain the temperature distribution within a cooled blade for 30 minutes in-service operation. There is no significant change in the temperature profiles across the nodal points, varying between 90oC – 600oC. The temperatures within the blade are significantly constant throughout the operating time of the turbine blade, inferring that there was effective heat transfer from the blades to the cooling air since the temperature variation did not exceed the melting point of the blade material. The ADI strategy is, therefore, suitable for heat transfer design computations for complex systems like the gas turbine engine.Item Hydraulic Transient Analysis in Fluid Pipeline: A Review(JOURNAL OF SCIENCE TECHNOLOGY AND EDUCATION , ATBU, BAUCHI, 2019-12-19) Muhammad, .A. B.; Nasir, .A.; Ayo, .S. A.; Bori IgeHydraulic transient is an important phenomenon in the pipeline transportation system that have adverse and catastrophic effects on the most susceptible pipeline components such as valve, pumps, pipes as well as the environment. The major causes of hydraulic transients are sudden or abrupt valve closure or pump failures as a result of power outage. The major challenges of transient analysis techniques are to optimally achieve a balance between accuracy of results obtained from the analysis and simplicity of the adopted techniques in analyzing both complex and simple pipeline networks. In order to attain this fit many researchers have proposed, developed and used different models and algorithms to this regards. This paper surveys various transient analysis techniques, model and algorithm for protection of pipeline network system with a view of achieving optimal trade-off between transient analysis techniques used and the type of fluid flow pipeline analyzed. Performance and limitations of some of the previous works are identified. Finally, future investigations on petroleum and its products were recommended.Item Hydraulic Transient Analysis of a Petroleum Pipeline Transporting Dual Purpose Kerosene Using Modelling and Simulation Approach(Premier Journal of Engineering and Applied Sciences, 2020-04-21) Muhammad, .A. B.; Nasir, .A.; Ayo, .S. A.; Bori IgeHydraulic transient analysis of a pipeline transporting dual purpose kerosene (DPK) was carried out in this research using simulation approach. Many petroleum pump stations and pipelines experience leakages and failures at their nodes due to changes in flow parameters that lead to hydraulic transient. Such types of unsteady situations are encountered frequently in pipelines where the valves are suddenly closed. WANDA Transient 4.5.1210 commercial software was used for the analysis of hydraulic transient. Variation in pressures and discharges with respect to time after the closure of a gate valve at the downstream of a pipeline were observed. It was observed in the study that pressure at node F rise significantly up to about 1354 kPa against the initial inlet pressure of 120 kPa due to the instantaneous valve closure and it was also observed that pressure at node B drops to a negative pressure of -101 kPa and hence the formation of cavitations at that node B and pipe P2. The analysis showed that the magnitude of the pressure surge decreases as the valve closure is increased. The research recommended that surge tanks should be installed at node F to stabilize the pressure surge and also air vessels are to be installed at nodes B to curtail damages due to cavitations.Item Investigation of the Effects of Hydraulic Transient due to Instantaneous Valve Closure in a Petroleum Pipeline(NIPES Journal of Science and Technology Research, 2020-06-01) Muhammad, .A. B.; Nasir, .A.; Ayo, .S. A.; Bori IgePressure surge analysis of petroleum pipeline transporting automotive gas oil (AGO) also known as Diesel oil was carried out in this research work. Pressure transient analysis is often more significant than the steady state analysis that engineers usually use in pipeline design. Pressure transient analysis helps to understand the additional pressures the pipeline can be subjected to as a result of instantaneous rapid valve closures or pump failure. The fluid pressure and flow rate in the pipeline system may change significantly at some intervals of time due to the valve closure and such types of unsteady situations are encountered more often in pipelines where the valves are suddenly closed. In this paper, pressure surge due to instantaneous valve closure in a petroleum pipeline conveying AGO was studied in a virtual environment. WANDA Transient 4.5.1210 commercial software was used for the analysis of the pressure surge in the pipeline due to instantaneous valve closure time of 4.75s. It was observed in the study that pressure at some nodes rise significantly up to about 1400 kPa against the initial inlet pressure of 120 kPa due to the instantaneous valve closure and it drastically drops at some nodes to negative pressure of about -100 kPa and hence the formation of cavitations. The analysis showed that the magnitude of the pressure surge decreases as the valve closure is increased.Item Numerical Investigation of Thermomechanical Fatigue Behavior in Aeroderivative Gas Turbine Blades(NIPES Journal of Science and Technology Research, 2021-08-31) Orah, .A. M.; Nasir, .A.; Hassan, .A. B.; Bori IgeThe hot gas component of the gas turbine engine comprises the burner, the turbine stages, and the exhaust nozzles/ducts. However, the turbine blades experience high thermal and mechanical loading. As a result, they suffer thermo-mechanical fatigue (TMF). The design process usually involves the appropriate selection of the turbine blade materials. Therefore, the need to carry out thermo-mechanical fatigue studies on gas turbine blades to predict blade life. During TMF loading, fatigue, oxidation, and creep damages are induced, and the relative contributions of these damages vary with the different materials and loading conditions. The study employed the finite element method to examine the high temperature and stress effects on the blades during TMF. The blade material considered in this study is a nickel-based super-alloy, Inconel 738 Low Carbon (IN738LC). The finite element method predicted the temperature and stress distributions in the blade, illustrating the blade sections prone to damage during thermomechanical fatigue. The equations from the law of heat conduction of Fourier and the cooling law of Newton predicted the heat transfer process of the interaction between the blade, hot gases, and cooling air. Therefore, the finite element method is suitable for studying the thermomechanical fatigue behavior of turbine blade metals, which is a precursor to blade life predictions.Item Investigation of the Temperature Variations in Aeroderivative Gas Turbine Blade Cooling(Journal of Materials Engineering, Structures and Computation, 2023-11-22) Orah, A. .M.; Nasir, .A.; Hassan, .A.B.; Bori Ige; Ayo, .S. A.In order to improve performance and efficiency, modern-day gas turbines operate at high temperatures. It is essential to use suitable cooling techniques on the blade and other hot areas since the elevated temperatures might exceed the metal melting temperature of the turbine blades. This paper presents the numerical modelling of heat exchange in a cooled aerodrivative gas turbine blade depending on the Newton’s law of cooling equation as governing equation, then integrating the heat transfer coefficient by convection into the alternating direction implicit (ADI) approach of computational fluid dynamics (CFD). Based on the chosen boundary conditions and the gas turbine's intended cooling characteristics, a model for the heat transfer problem was created. A MATLAB code was developed to ascertain the temperature variations inside a cooling blade for a half-hour in-service operation. This study found a temperature difference between the transient and final temperature values of roughly 25 to 300oC, demonstrating the heat transfer process between the hot gases and the coolant air. It inferred effective heat transmission from the blades to the cooling air because the temperature differential within the blades did not rise over the melting point of the blade material and it yielded an average blade temperature of 400°C. Thus, the ADI technique is appropriate for heat transfer design calculations for intricate devices such as the gas turbine engine.