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Papers by Emmanuel Obuah
Physics Letters B, 2017
We compare the reconstructed hadronization conditions in relativistic nuclear collisions in the n... more We compare the reconstructed hadronization conditions in relativistic nuclear collisions in the nucleon-nucleon centre-of-mass energy range 4.7-2760 GeV in terms of temperature and baryonchemical potential with lattice QCD calculations, by using hadronic multiplicities. We obtain hadronization temperatures and baryon chemical potentials with a fit to measured multiplicities by correcting for the effect of post-hadronization rescattering. The post-hadronization modification factors are calculated by means of a coupled hydrodynamical-transport model simulation under the same conditions of approximate isothermal and isochemical decoupling as assumed in the statistical hadronization model fits to the data. The fit quality is considerably better than without rescattering corrections, as already found in previous work. The curvature of the obtained "true" hadronization pseudo-critical line κ is found to be 0.0048 ± 0.0026, in agreement with lattice QCD estimates; the pseudo-critical temperature at vanishing µB is found to be 164.3 ± 1.8 MeV.
Journal of Renewable and Sustainable Energy, 2014
FIG. 1. The map of Nigeria showing the selected location of the case study.
Energy supply is a prerequisite for enhancing industrial development in every nation. Unreliable ... more Energy supply is a prerequisite for enhancing industrial development in every nation. Unreliable power supply which is peculiar to many developing nations particularly the sub-Sahara African countries has been reported to be grossly responsible for the poor growth industries. Hybrid energy system which combines two or more than two energy conversion devices or two or more than two fuels for generation of power has been used in different regions to enhance the sustainability of electricity supply. This paper presents a hybrid Photovoltaic/diesel energy system configured to serve a peak load (AC) of 18kW. With fuel price displaying an upward trend in recent time, it is expected that price increases would occur during the project lifetime. The then paper focuses on sensitivity analysis of hybrid PV/diesel energy system for an oil and gas industries in Nigeria. The research considered six cases of $0.1 per liter fuel pump price increment for 20 years project life time each. The study ...
The use of self-excited synchronous reluctance generator is gaining interest due to its simplicit... more The use of self-excited synchronous reluctance generator is gaining interest due to its simplicity and inexpensiveness in terms of manufacturing. The problem of this machine which is best suited in a standalone application is that it has poor power factor. This paper presents a comparative study of a PM assisted synchronous reluctance generator with a regular reluctant generator. The machine was studied using rotor rotating frame and embedded MATLAB was used to simulate the machine. Results shows that the generator with PM exhibited a better performance in terms of voltage and power output due to the PM flux. This was possible at power factor of 0.999 and excitation capacitor value of 70uF and PM flux of 0.8. Reducing the value of the excitation capacitor hampered the generator performance. However, increasing the PM flux at the lower capacitor, produces a suitable voltage for the generator. Keywords: PM Flux, Excitation capacitor, Output power, Voltage build up, Torque. Cite this A...
Iconic Research And Engineering Journals, 2018
Solar photovoltaic (PV) is currently the fastest growing power generation technology in the world... more Solar photovoltaic (PV) is currently the fastest growing power generation technology in the world. The performance of PV modules depends upon the geographical factors such as solar intensity, longitude, latitude; and the environmental factors such as humidity, pollution, temperature, wind, dust, rain, etc. Design assumption has been a major research topic in PV systems and has usually been concentrated in studies on radiation availability, efficient operating strategies design and sizing of these systems. On the other hand, the influence of environmental factors such as debris on the performance of PV systems has not been given much attention, particularly in Port Harcourt region of Nigeria. In this work, electrical performances of photovoltaic systems are studied empirically with their effect of soot. The experimental results obtained were used for the calculation of the energy efficiency and power output of the PV systems. It was found that the average reduction of PV efficiency was 12%. It was also observed that power reduction was due to soot in form of carbon particles accumulated on the panel.
Physics Letters B, 2017
We compare the reconstructed hadronization conditions in relativistic nuclear collisions in the n... more We compare the reconstructed hadronization conditions in relativistic nuclear collisions in the nucleon-nucleon centre-of-mass energy range 4.7-2760 GeV in terms of temperature and baryonchemical potential with lattice QCD calculations, by using hadronic multiplicities. We obtain hadronization temperatures and baryon chemical potentials with a fit to measured multiplicities by correcting for the effect of post-hadronization rescattering. The post-hadronization modification factors are calculated by means of a coupled hydrodynamical-transport model simulation under the same conditions of approximate isothermal and isochemical decoupling as assumed in the statistical hadronization model fits to the data. The fit quality is considerably better than without rescattering corrections, as already found in previous work. The curvature of the obtained "true" hadronization pseudo-critical line κ is found to be 0.0048 ± 0.0026, in agreement with lattice QCD estimates; the pseudo-critical temperature at vanishing µB is found to be 164.3 ± 1.8 MeV.
Journal of Renewable and Sustainable Energy, 2014
FIG. 1. The map of Nigeria showing the selected location of the case study.
Energy supply is a prerequisite for enhancing industrial development in every nation. Unreliable ... more Energy supply is a prerequisite for enhancing industrial development in every nation. Unreliable power supply which is peculiar to many developing nations particularly the sub-Sahara African countries has been reported to be grossly responsible for the poor growth industries. Hybrid energy system which combines two or more than two energy conversion devices or two or more than two fuels for generation of power has been used in different regions to enhance the sustainability of electricity supply. This paper presents a hybrid Photovoltaic/diesel energy system configured to serve a peak load (AC) of 18kW. With fuel price displaying an upward trend in recent time, it is expected that price increases would occur during the project lifetime. The then paper focuses on sensitivity analysis of hybrid PV/diesel energy system for an oil and gas industries in Nigeria. The research considered six cases of $0.1 per liter fuel pump price increment for 20 years project life time each. The study ...
The use of self-excited synchronous reluctance generator is gaining interest due to its simplicit... more The use of self-excited synchronous reluctance generator is gaining interest due to its simplicity and inexpensiveness in terms of manufacturing. The problem of this machine which is best suited in a standalone application is that it has poor power factor. This paper presents a comparative study of a PM assisted synchronous reluctance generator with a regular reluctant generator. The machine was studied using rotor rotating frame and embedded MATLAB was used to simulate the machine. Results shows that the generator with PM exhibited a better performance in terms of voltage and power output due to the PM flux. This was possible at power factor of 0.999 and excitation capacitor value of 70uF and PM flux of 0.8. Reducing the value of the excitation capacitor hampered the generator performance. However, increasing the PM flux at the lower capacitor, produces a suitable voltage for the generator. Keywords: PM Flux, Excitation capacitor, Output power, Voltage build up, Torque. Cite this A...
Iconic Research And Engineering Journals, 2018
Solar photovoltaic (PV) is currently the fastest growing power generation technology in the world... more Solar photovoltaic (PV) is currently the fastest growing power generation technology in the world. The performance of PV modules depends upon the geographical factors such as solar intensity, longitude, latitude; and the environmental factors such as humidity, pollution, temperature, wind, dust, rain, etc. Design assumption has been a major research topic in PV systems and has usually been concentrated in studies on radiation availability, efficient operating strategies design and sizing of these systems. On the other hand, the influence of environmental factors such as debris on the performance of PV systems has not been given much attention, particularly in Port Harcourt region of Nigeria. In this work, electrical performances of photovoltaic systems are studied empirically with their effect of soot. The experimental results obtained were used for the calculation of the energy efficiency and power output of the PV systems. It was found that the average reduction of PV efficiency was 12%. It was also observed that power reduction was due to soot in form of carbon particles accumulated on the panel.