This page has only limited features, please log in for full access.

Unclaimed
Fidelis I. Abam
Energy, Exergy and Environment Research Group (EEERG), Department of Mechanical Engineering, Michael Okpara University of Agriculture Umudike, Nigeria

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 06 August 2021 in Scientific African
Reads 0
Downloads 0

The paper presents the comparative evaluation of the homogenous and the drift-flux flow modelling techniques employed in a three-phase downward flow in a vertical pipe. The study's objective is to analyse and compare the pressure drop of an experimental procedure of three-phase flow in a downward vertical pipe based on the two modelling techniques. The considered fluids include CO2 gas and the homogenous water and oil phases. The results show that the CO2 gas and the homogenous water and oil phases' velocities were obtained between 0.452 and 32.868 m/s and 0.008889 and 13.0734 m/s at 20, 50, 70 and 90% water cuts (WCs), respectively. On the other hand, the pressure drop (PD) ranged between 336.75≤PD≤4570.431 N/m3 and 27.741≤PD≤−2176.769 N/m3 for the homogenous and drift-flux models. A comparative evaluation between the two models established an excellent agreement with over-prediction. Additionally, at all WCs, the total PD shows an over-prediction of 8.685 % for the homogenous model and an under-prediction of 12.91% for the drift-flux. Hence, the homogenous modelling technique gave a higher efficiency and was recommended for the determination of the total pressure drop. Conversely, the drift-flux model was established to precisely determine the effect of single-phase flow properties on the total pressure drop of the flow process. The findings further provided a comprehensive understanding of introducing CO2 gas in a three-phase downward flow process to meet the demands of emerging technologies.

ACS Style

Fidelis I. Abam; Ntunde I. Dilibe; Bethrand N. Nwankwojike; Ogheneruona Diemuodeke; Isaac John. Comparative evaluation of homogenous and drift-flux models for a three-phase downward flow in a pipe. Scientific African 2021, 13, e00898 .

AMA Style

Fidelis I. Abam, Ntunde I. Dilibe, Bethrand N. Nwankwojike, Ogheneruona Diemuodeke, Isaac John. Comparative evaluation of homogenous and drift-flux models for a three-phase downward flow in a pipe. Scientific African. 2021; 13 ():e00898.

Chicago/Turabian Style

Fidelis I. Abam; Ntunde I. Dilibe; Bethrand N. Nwankwojike; Ogheneruona Diemuodeke; Isaac John. 2021. "Comparative evaluation of homogenous and drift-flux models for a three-phase downward flow in a pipe." Scientific African 13, no. : e00898.

Brief communication
Published: 01 July 2021 in Discover Chemical Engineering
Reads 0
Downloads 0

Numerical modeling of biomass pyrolysis is becoming a cost and time-saving alternative for experimental investigations, also to predict the yield of the by-products of the entire process. In the present study, a two-step parallel kinetic model was used to predict char yield under isothermal condition. MATLAB ODE45 function codes were employed to solve a set of differential equations that predicts the %char at varying residence times and temperatures. The code shows how the various kinetic parameters and mass of pyrolysis products were determined. Nevertheless, the algorithm used for the prediction was validated with experimental data and results from past works. At 673.15 K, the numerical simulation using ODE45 function gives a char yield of 27.84%. From 573.15 K to 673.15 K, char yield ranges from 31.7 to 33.72% to 27.84% while experimental yield decreases from 44 to 22%. Hence, the error between algorithm prediction and experimental data from literature is − 0.26 and 0.22. Again, comparing the result of the present work with the analytical method from the literature showed a good agreement.

ACS Style

Ibiba Taiwo Horsfall; Macmanus Chinenye Ndukwu; Fidelis Ibiang Abam; Ololade Moses Olatunji; Ojong Elias Ojong; Keavey Osa-Aria. Validation of MATLAB algorithm to implement a two-step parallel pyrolysis model for the prediction of maximum %char yield. Discover Chemical Engineering 2021, 1, 1 -11.

AMA Style

Ibiba Taiwo Horsfall, Macmanus Chinenye Ndukwu, Fidelis Ibiang Abam, Ololade Moses Olatunji, Ojong Elias Ojong, Keavey Osa-Aria. Validation of MATLAB algorithm to implement a two-step parallel pyrolysis model for the prediction of maximum %char yield. Discover Chemical Engineering. 2021; 1 (1):1-11.

Chicago/Turabian Style

Ibiba Taiwo Horsfall; Macmanus Chinenye Ndukwu; Fidelis Ibiang Abam; Ololade Moses Olatunji; Ojong Elias Ojong; Keavey Osa-Aria. 2021. "Validation of MATLAB algorithm to implement a two-step parallel pyrolysis model for the prediction of maximum %char yield." Discover Chemical Engineering 1, no. 1: 1-11.

Journal article
Published: 05 June 2021 in Energy Reports
Reads 0
Downloads 0

The paper presents the environmental sustainability of the Nigeria transport sector (NTPS) through the decomposition and decoupling analysis from 1988–2019. The study’s objective is to determine ways of saving energy in the NTPS and reduce carbon emission for a sustainable environment. The approach was based on the Logarithmic Mean Divisa Index (LMDI) and the Tapio approach, built on Kaya extended identity. Five decoupling indicators were considered based on the four energy carriers consumed in the NTPS. The indicators include economic activity, energy structure, economic structure, population and energy intensity. The results identified three decoupling states, weak negative decoupling, weak decoupling and strong decoupling. The energy intensity, economic activity, population and energy structure prevented decoupling during the study period, while the economic structure factor promoted decoupling. The overall impact of carbon emissions from NTPS was calculated at 44.45 million tonnes of CO2. The study suggests frameworks that will support policy makers to formulate broad base policies for environmental sustainability.

ACS Style

Fidelis I. Abam; Ekwe B. Ekwe; Ogheneruona E. Diemuodeke; Michael I. Ofem; Bassey B. Okon; Chukwuma H. Kadurumba; Archibong Archibong-Eso; Samuel O. Effiom; Jerome G. Egbe; Wisdom E. Ukueje. Environmental sustainability of the Nigeria transport sector through decomposition and decoupling analysis with future framework for sustainable transport pathways. Energy Reports 2021, 7, 3238 -3248.

AMA Style

Fidelis I. Abam, Ekwe B. Ekwe, Ogheneruona E. Diemuodeke, Michael I. Ofem, Bassey B. Okon, Chukwuma H. Kadurumba, Archibong Archibong-Eso, Samuel O. Effiom, Jerome G. Egbe, Wisdom E. Ukueje. Environmental sustainability of the Nigeria transport sector through decomposition and decoupling analysis with future framework for sustainable transport pathways. Energy Reports. 2021; 7 ():3238-3248.

Chicago/Turabian Style

Fidelis I. Abam; Ekwe B. Ekwe; Ogheneruona E. Diemuodeke; Michael I. Ofem; Bassey B. Okon; Chukwuma H. Kadurumba; Archibong Archibong-Eso; Samuel O. Effiom; Jerome G. Egbe; Wisdom E. Ukueje. 2021. "Environmental sustainability of the Nigeria transport sector through decomposition and decoupling analysis with future framework for sustainable transport pathways." Energy Reports 7, no. : 3238-3248.

Review
Published: 18 May 2021
Reads 0
Downloads 0

The hygrothermal transfer is very important for the design of a building envelope for thermal comfort and economic and energy analysis of the building envelope. The applications of various materials in building envelope have been studied extensively. The study presents several models for the hygrothermal transfer for various building walls. Several energy and mass conservation equations with different boundary conditions and input considerations were presented in this paper for concrete, bricks and wooden walls. The effect of hysteresis was ignored in developing most model equations, while few considered flow pattern of fluid through the wall surfaces. Due to the flexibility of Luikov models, it formed the basis for modelling the coupled heat and mass transfer for porous material independent of hygroscopic nature with different boundary conditions defined according to the geometry and orientations. The influence of type of wall, orientation, thickness, the density of the material and climatic variations on the temperature and moisture evolutions within the building materials was more pronounced. Literature, presenting imaging models using imagery software like COMSOL multi-physics, CFD etc. were scarce considering that microscopic imagery is now deployed to measure the heat and moisture evolution in materials. Future models should include shrinkage or expansion influence on the fibrous material like wood due to their behaviour under environmental condition.

ACS Style

Macmanus Chinenye Ndukwu; Merlin Simo-Tagne; Ifiok Edem Ekop; Mathew I. Ibeh; Maureen A. Allen; Fidelis. I. Abam; Razika Kharchi. Energy in buildings: A review of models on hygrothermal transfer through the porous materials for building envelop. 2021, 1 .

AMA Style

Macmanus Chinenye Ndukwu, Merlin Simo-Tagne, Ifiok Edem Ekop, Mathew I. Ibeh, Maureen A. Allen, Fidelis. I. Abam, Razika Kharchi. Energy in buildings: A review of models on hygrothermal transfer through the porous materials for building envelop. . 2021; ():1.

Chicago/Turabian Style

Macmanus Chinenye Ndukwu; Merlin Simo-Tagne; Ifiok Edem Ekop; Mathew I. Ibeh; Maureen A. Allen; Fidelis. I. Abam; Razika Kharchi. 2021. "Energy in buildings: A review of models on hygrothermal transfer through the porous materials for building envelop." , no. : 1.

Journal article
Published: 18 November 2020 in Energies
Reads 0
Downloads 0

There is a burden of adequate energy supply for meeting demand and reducing emission to avoid the average global temperature of above 2 °C of the pre-industrial era. Therefore, this study presents the exergoeconomic and environmental analysis of a proposed integrated multi-generation plant (IMP), with supplemental biomass-based syngas firing. An in-service gas turbine plant, fired by natural gas, was retrofitted with a gas turbine (GT), steam turbine (ST), organic Rankine cycle (ORC) for cooling and power production, a modified Kalina cycle (KC) for power production and cooling, and a vapour absorption system (VAB) for cooling. The overall network, energy efficiency, and exergy efficiency of the IMP were estimated at 183 MW, 61.50% and 44.22%, respectively. The specific emissions were estimated at 122.2, 0.222, and 3.0 × 10−7 kg/MWh for CO2, NOx, and CO, respectively. Similarly, the harmful fuel emission factor, and newly introduced sustainability indicators—exergo-thermal index (ETI) and exergetic utility exponent (EUE)—were obtained as 0.00067, 0.675, and 0.734, respectively. The LCC of $1.58 million was obtained, with a payback of 4 years, while the unit cost of energy was estimated at 0.0166 $/kWh. The exergoeconomic factor and the relative cost difference of the IMP were obtained as 50.37% and 162.38%, respectively. The optimum operating parameters obtained by a genetic algorithm gave the plant’s total cost rate of 125.83 $/hr and exergy efficiency of 39.50%. The proposed system had the potential to drive the current energy transition crisis caused by the COVID-19 pandemic shock in the energy sector.

ACS Style

Fidelis. Abam; Ogheneruona Diemuodeke; Ekwe. Ekwe; Mohammed Alghassab; Olusegun Samuel; Zafar Khan; Muhammad Imran; Muhammad Farooq. Exergoeconomic and Environmental Modeling of Integrated Polygeneration Power Plant with Biomass-Based Syngas Supplemental Firing. Energies 2020, 13, 6018 .

AMA Style

Fidelis. Abam, Ogheneruona Diemuodeke, Ekwe. Ekwe, Mohammed Alghassab, Olusegun Samuel, Zafar Khan, Muhammad Imran, Muhammad Farooq. Exergoeconomic and Environmental Modeling of Integrated Polygeneration Power Plant with Biomass-Based Syngas Supplemental Firing. Energies. 2020; 13 (22):6018.

Chicago/Turabian Style

Fidelis. Abam; Ogheneruona Diemuodeke; Ekwe. Ekwe; Mohammed Alghassab; Olusegun Samuel; Zafar Khan; Muhammad Imran; Muhammad Farooq. 2020. "Exergoeconomic and Environmental Modeling of Integrated Polygeneration Power Plant with Biomass-Based Syngas Supplemental Firing." Energies 13, no. 22: 6018.

Journal article
Published: 04 November 2020 in International Journal of Sustainable Engineering
Reads 0
Downloads 0
ACS Style

M. C. Ndukwu; D. I. Onwude; L. Bennamoun; F. I. Abam; M. Simo-Tagne; I. T. Horsfall; T.A. Briggs. Nigeria’s Energy deficit: The challenges and Eco- friendly approach in reducing the energy gap. International Journal of Sustainable Engineering 2020, 1 -18.

AMA Style

M. C. Ndukwu, D. I. Onwude, L. Bennamoun, F. I. Abam, M. Simo-Tagne, I. T. Horsfall, T.A. Briggs. Nigeria’s Energy deficit: The challenges and Eco- friendly approach in reducing the energy gap. International Journal of Sustainable Engineering. 2020; ():1-18.

Chicago/Turabian Style

M. C. Ndukwu; D. I. Onwude; L. Bennamoun; F. I. Abam; M. Simo-Tagne; I. T. Horsfall; T.A. Briggs. 2020. "Nigeria’s Energy deficit: The challenges and Eco- friendly approach in reducing the energy gap." International Journal of Sustainable Engineering , no. : 1-18.

Journal article
Published: 12 March 2020 in Renewable Energy
Reads 0
Downloads 0

The paper presents an active mix-mode wind-powered fan solar dryer (AWPFS) with a passive mix-mode non-wind-powered solar dryer (PNWPS) evaluated with pre-treated potato slices. The two dryers were tested with and without glycerol as thermal energy storage. The objective was to present a non-electricity powered active solar dryer using only clean energy sources. Evaluation of the dryer took place at ambient temperature range of 24–50 °C and humidity of 10–52%. The results indicate that drying with AWPFS integrated with glycerol showed shorter drying time than drying with AWPFS only or PNWPS. Dipping the potato in a salt solution and blanching for 30 s before drying quickened the drying rate of the potato compared to other treatments. The energy consumed for drying ranged from 4.10 to 4.98 MJ, while the specific energy consumption ranged from 2.846 to 3.686 kWh/kg. The drying efficiencies ranged from 25.031% to 31.5%, while the exergy efficiency ranged from 14.5 to 80.9%. With low electricity penetration density across Africa, this dryer with naturally powered fan will help crop processors dry their product faster and about 15.3–290.4 $/year could be saved at 10–100% rate of usage

ACS Style

M.C. Ndukwu; D. Onyenwigwe; F.I. Abam; A.B. Eke; C. Dirioha. Development of a low-cost wind-powered active solar dryer integrated with glycerol as thermal storage. Renewable Energy 2020, 154, 553 -568.

AMA Style

M.C. Ndukwu, D. Onyenwigwe, F.I. Abam, A.B. Eke, C. Dirioha. Development of a low-cost wind-powered active solar dryer integrated with glycerol as thermal storage. Renewable Energy. 2020; 154 ():553-568.

Chicago/Turabian Style

M.C. Ndukwu; D. Onyenwigwe; F.I. Abam; A.B. Eke; C. Dirioha. 2020. "Development of a low-cost wind-powered active solar dryer integrated with glycerol as thermal storage." Renewable Energy 154, no. : 553-568.

Journal article
Published: 12 February 2020 in Heliyon
Reads 0
Downloads 0

The aim of this study is to present a new hybrid solar-biomass dryer and carry out thermal analysis based on energy and exergo-sustainability analysis considering all the available exergy stream of solar radiation, air stream through the collector, and exergy of the moisture in the product. The research also presented the environmental impact and economic analysis of using the dryer. Performance evaluations show that at collector efficiency of 20.81%–21.89 %, the developed solar dryers can save between 10 – 21hrs of drying time in drying 5 mm thick plantain slices to 15 % moisture content from initial moisture content of 66 % w.b when compared to drying under the open sun. The improvement potential ranged from 0.036 to 20.6W while the waste exergy ratios and sustainability index ranged from 0.38 - 0.55 and 2.3–6.11 respectively. Application of the solar dryers can save between 44 -3074 of CO2 entering the atmosphere per year while 2.94 to 205.43$ could also be saved at 10–100% rate of usage when compared to diesel fired dryer. The total energy consumption for drying ranges between 5.52 and 35.47 MJ, while the specific energy consumption ranged from 4.3 to 26.2 kWh/kg. The exergy efficiency ranges from 5.6 – 95.13 % during the sunshine hours.

ACS Style

Macmanus Ndukwu; M. Simo-Tagne; Fidelis Abam; O.S. Onwuka; S. Prince; L. Bennamoun. Exergetic sustainability and economic analysis of hybrid solar-biomass dryer integrated with copper tubing as heat exchanger. Heliyon 2020, 6, e03401 .

AMA Style

Macmanus Ndukwu, M. Simo-Tagne, Fidelis Abam, O.S. Onwuka, S. Prince, L. Bennamoun. Exergetic sustainability and economic analysis of hybrid solar-biomass dryer integrated with copper tubing as heat exchanger. Heliyon. 2020; 6 (2):e03401.

Chicago/Turabian Style

Macmanus Ndukwu; M. Simo-Tagne; Fidelis Abam; O.S. Onwuka; S. Prince; L. Bennamoun. 2020. "Exergetic sustainability and economic analysis of hybrid solar-biomass dryer integrated with copper tubing as heat exchanger." Heliyon 6, no. 2: e03401.

Journal article
Published: 27 September 2019 in Scientific African
Reads 0
Downloads 0

The number of impeller slots, slot angle (angulations), and rotational speed are some of the operational parameters that influence kernel yield of centrifugal impact nut shellers. The effects of these three parameters on Bambara nut kernel extraction using a horizontal placed centrifugal Bambara nutcracker with a capacity of 150.6 kg/hr at a speed of 2200 rpm was determined using a split plot factorial experimental design. The dehulling efficiency increased with increase in rotational speed and number of impeller slots with a maximum value of 90.5% obtained at the highest speed of 2251 rpm, 75oangulations and 4 impeller slots while the minimum dehulling efficiency was 59% obtained at the lowest speed of 1125.8 rpm, 60o angulations, and 2 impeller slots. This range of values produced an extraction yield of 79.7– 84.5% and broken kernel of 11-59.6%. The results were fitted and responses were plotted and statistically analyzed to obtain the relationships between the variables. The optimum range of dehulling efficiency was 75.67 - 87.94% at rotational speed of 1956.42 -2135.74 rpm, angulations of 67.82o - 90o and 2-4 impeller slots. The optimum kernel yield ranged from 83.54-84.98 % at 1125.8 -1228.78 rpm, 47-90o and 2 -4 slots while the optimum kernel damage was 12.56 -15.19 % at 1126.46 -1131.3 rpm, 2-4 slots and 90o angulations. However, from the coefficient Table, it was only the speed and interaction of speed and angulations that significantly affected the nut dehulling efficiency and kernel yield respectively at p < 0.05.

ACS Style

M.C. Ndukwu; I.E. Ekop; P.J. Etim; C.N. Ohakwe; N.R. Ezejiofor; D.I. Onwude; F.I. Abam; E.C. Igboayaka; A. Ohia. Response surface optimization of Bambara nut kernel yield as affected by speed of rotation, and impeller configurations. Scientific African 2019, 6, e00174 .

AMA Style

M.C. Ndukwu, I.E. Ekop, P.J. Etim, C.N. Ohakwe, N.R. Ezejiofor, D.I. Onwude, F.I. Abam, E.C. Igboayaka, A. Ohia. Response surface optimization of Bambara nut kernel yield as affected by speed of rotation, and impeller configurations. Scientific African. 2019; 6 ():e00174.

Chicago/Turabian Style

M.C. Ndukwu; I.E. Ekop; P.J. Etim; C.N. Ohakwe; N.R. Ezejiofor; D.I. Onwude; F.I. Abam; E.C. Igboayaka; A. Ohia. 2019. "Response surface optimization of Bambara nut kernel yield as affected by speed of rotation, and impeller configurations." Scientific African 6, no. : e00174.

Conference paper
Published: 05 August 2019 in Day 3 Wed, August 07, 2019
Reads 0
Downloads 0

This research entails evaluation of existing interfacial friction factor, gas-wall shear stress, and liquid wall shear stress correlations for the prediction of liquid holdup in pipelines. In addition, a statistical analysis was conducted on the predicted and measured flow parameters. Stratified horizontal two-phase flow equation was used in deriving an equation that solves for liquid holdup that is dependent on the interfacial shear stress. The model was implemented in a MATLAB integrated development environment to observe the effect of interfacial friction factors obtained from existing correlations. The results obtained from the comparative study of selected friction factors indicate that some of the correlations show high deviation from experimentally determined values. The largest deviation was observed in the model proposed by Sinai which was because of the condition for which it was originally developed is not suited for horizontal stratified two-phase gas-liquid flow. It was also observed that the correlation of Petalas and Aziz gave the best result and least deviation from the measured values. The performance of each correlation was observed to vary with the assumed values of liquid height. All the correlations gave good predictions at 30% liquid height but performed poorly at 40% liquid height.

ACS Style

Mobolaji Abegunde; Tobinson Briggs; Fidelis Abam; Tayo Awolola. Evaluation of Interfacial Friction Models in Stratified Flow: Gas-Liquid Two-Phase Flow. Day 3 Wed, August 07, 2019 2019, 1 .

AMA Style

Mobolaji Abegunde, Tobinson Briggs, Fidelis Abam, Tayo Awolola. Evaluation of Interfacial Friction Models in Stratified Flow: Gas-Liquid Two-Phase Flow. Day 3 Wed, August 07, 2019. 2019; ():1.

Chicago/Turabian Style

Mobolaji Abegunde; Tobinson Briggs; Fidelis Abam; Tayo Awolola. 2019. "Evaluation of Interfacial Friction Models in Stratified Flow: Gas-Liquid Two-Phase Flow." Day 3 Wed, August 07, 2019 , no. : 1.

Journal article
Published: 07 May 2019 in Journal of Quality in Maintenance Engineering
Reads 0
Downloads 0

Purpose The purpose of this paper is to propose a software (Equipment State Simulator) used for predicting equipment performance parameters required for maintenance planning. Design/methodology/approach This maintenance software was developed from the derived stable state probability models using algebraic substitution and computation of total operational period, number of breakdowns, total downtime, mean time between failures and mean time to repair of equipment/component(s) at preventive maintenance and corrective maintenance states. The models were derived using mechanistic modeling technique such that all the relevant variables were accounted for. Findings Analysis of this software revealed that its predictions reckon with the actual performance of the test specimens by about 99 percent. Originality/value The research proposes a maintenance model and software for predicting state probabilities of manufacturing systems degradation. This program also predicts maintenance action(s) required by the equipment based on the predetermined alert levels.

ACS Style

Chibundo Princewill Nwadinobi; Bethrand Nduka Nwankwojike; Fidelis Ibiang Abam. Improved Markov stable state simulation for maintenance planning. Journal of Quality in Maintenance Engineering 2019, 25, 199 -212.

AMA Style

Chibundo Princewill Nwadinobi, Bethrand Nduka Nwankwojike, Fidelis Ibiang Abam. Improved Markov stable state simulation for maintenance planning. Journal of Quality in Maintenance Engineering. 2019; 25 (2):199-212.

Chicago/Turabian Style

Chibundo Princewill Nwadinobi; Bethrand Nduka Nwankwojike; Fidelis Ibiang Abam. 2019. "Improved Markov stable state simulation for maintenance planning." Journal of Quality in Maintenance Engineering 25, no. 2: 199-212.

Articles
Published: 26 November 2018 in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects
Reads 0
Downloads 0

A thermodynamic modification of an ORC integrated with turbine bleeding and regeneration (ORCTBR) is presented. The objective is to modify the ORCTBR for both cooling and power generation (ORCNOV). First, a thermodynamic break down of the components based on exergy was performed followed by a sensitivity analysis. The results indicate that at based conditions the maximum efficiency obtained with ORCNOV was about 52% using R245fa at a heat input of 252 kW. The improvement in efficiency was estimated at 7.2% when compared with ORCTBR. The highest cooling rate was achieved using R1234yf, R245fa, and R1234ze by 11.14, 10.60, and 10.11 kW, respectively. Additionally, the ORCNOV showed improved performance in turbine output power of approximately 2%. However, the sensitivity studies show that the exergy destruction gap was not greater than 45% between the ORCTBR and ORCNOV, and high cooling rates are feasible at increased condenser (1) pressure.

ACS Style

Fidelis I. Abam; Tobinson A. Briggs; Ekwe B. Ekwe; C. G. Kanu; Samuel O. Effiom; Macmanus Ndukwu; S. O. Ohunakin; Michael Ofem. Exergy analysis of a novel low-heat recovery organic Rankine cycle (ORC) for combined cooling and power generation. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 2018, 41, 1649 -1662.

AMA Style

Fidelis I. Abam, Tobinson A. Briggs, Ekwe B. Ekwe, C. G. Kanu, Samuel O. Effiom, Macmanus Ndukwu, S. O. Ohunakin, Michael Ofem. Exergy analysis of a novel low-heat recovery organic Rankine cycle (ORC) for combined cooling and power generation. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2018; 41 (13):1649-1662.

Chicago/Turabian Style

Fidelis I. Abam; Tobinson A. Briggs; Ekwe B. Ekwe; C. G. Kanu; Samuel O. Effiom; Macmanus Ndukwu; S. O. Ohunakin; Michael Ofem. 2018. "Exergy analysis of a novel low-heat recovery organic Rankine cycle (ORC) for combined cooling and power generation." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 41, no. 13: 1649-1662.

Journal article
Published: 01 November 2018 in Energy Reports
Reads 0
Downloads 0
ACS Style

Fidelis Abam; E.B. Ekwe; S.O. Effiom; Macmanus Ndukwu. A comparative performance analysis and thermo-sustainability indicators of modified low-heat organic Rankine cycles (ORCs): An exergy-based procedure. Energy Reports 2018, 4, 110 -118.

AMA Style

Fidelis Abam, E.B. Ekwe, S.O. Effiom, Macmanus Ndukwu. A comparative performance analysis and thermo-sustainability indicators of modified low-heat organic Rankine cycles (ORCs): An exergy-based procedure. Energy Reports. 2018; 4 ():110-118.

Chicago/Turabian Style

Fidelis Abam; E.B. Ekwe; S.O. Effiom; Macmanus Ndukwu. 2018. "A comparative performance analysis and thermo-sustainability indicators of modified low-heat organic Rankine cycles (ORCs): An exergy-based procedure." Energy Reports 4, no. : 110-118.

Journal article
Published: 31 October 2018 in International Review of Mechanical Engineering (IREME)
Reads 0
Downloads 0
ACS Style

John Chijioke Edeh; Bethrand N. Nwankwojike; Fidelis Abam. Parametric Optimization of Improved Cassava Attrition Peeling Machine Using RSM Based Desirability Function. International Review of Mechanical Engineering (IREME) 2018, 12, 823 .

AMA Style

John Chijioke Edeh, Bethrand N. Nwankwojike, Fidelis Abam. Parametric Optimization of Improved Cassava Attrition Peeling Machine Using RSM Based Desirability Function. International Review of Mechanical Engineering (IREME). 2018; 12 (10):823.

Chicago/Turabian Style

John Chijioke Edeh; Bethrand N. Nwankwojike; Fidelis Abam. 2018. "Parametric Optimization of Improved Cassava Attrition Peeling Machine Using RSM Based Desirability Function." International Review of Mechanical Engineering (IREME) 12, no. 10: 823.

Journal article
Published: 21 September 2018 in Sustainable Energy Technologies and Assessments
Reads 0
Downloads 0

The optimum exergetic performance parameters and thermo-sustainability indicators (TSIs) of low-temperature Organic Rankine cycles (ORCs) are presented. The study objectives are (i) to determine the exergetic performance, and TSIs of modified ORCs based on different thermodynamic inputs and (ii) compare the optimum exergetic performance parameters and the TSIs of the ORCs. The TSIs considered include, waste exergy ratio (WER), exergy efficiency (EE), exergetic sustainability index (ESI) and environmental effect factor (EEF). Additionally, a component by component exergy analysis was first performed, followed by the application of the TSI models established by modifying the existing TSI model for open cycle thermal plants. The results indicated that the increase in EE across the ORCs was not greater than 0.3%. The exergy destruction gap across the ORCs was between 1.2 and 23%. The ESI was low with the basic ORC while the modified systems had improved ESIs. However, best exergetic performance and TSIs were obtained at optimum conditions of 0.127≤p1≤2.144MPa, 0.17≤p2≤2.5MPa and 416≤t3≤426. The study inferred that system configuration and type of working fluids are paramount in determining the ORC performance. Moreover, the results obtained can further be used to evaluate the functional sustainability limits of working fluids.

ACS Style

F.I. Abam; E.B. Ekwe; S.O. Effiom; M.C. Ndukwu; T.A. Briggs; C.H. Kadurumba. Optimum exergetic performance parameters and thermo-sustainability indicators of low-temperature modified organic Rankine cycles (ORCs). Sustainable Energy Technologies and Assessments 2018, 30, 91 -104.

AMA Style

F.I. Abam, E.B. Ekwe, S.O. Effiom, M.C. Ndukwu, T.A. Briggs, C.H. Kadurumba. Optimum exergetic performance parameters and thermo-sustainability indicators of low-temperature modified organic Rankine cycles (ORCs). Sustainable Energy Technologies and Assessments. 2018; 30 ():91-104.

Chicago/Turabian Style

F.I. Abam; E.B. Ekwe; S.O. Effiom; M.C. Ndukwu; T.A. Briggs; C.H. Kadurumba. 2018. "Optimum exergetic performance parameters and thermo-sustainability indicators of low-temperature modified organic Rankine cycles (ORCs)." Sustainable Energy Technologies and Assessments 30, no. : 91-104.

Review article
Published: 29 August 2018 in Food Engineering Reviews
Reads 0
Downloads 0

Africa has a very high solar insolation and a large agrarian sector with a lot of drying of agricultural products carried out with mostly open sun drying. However, efforts have been made by researchers based in Africa working, under changing climatic conditions, to develop solar drying systems, using materials that are locally available. The challenge was that the solar dryers should be used to dry different kinds of products including fish, medicinal plants, fruits, wood, and vegetables and bring the studied material to low moisture content. Most of this research has been obscured since Africa is not at the forefront of solar research, coupled with technological and economic laid-backness. The solar dryers’ designs consist of direct, indirect natural or forced convection dryers or even mixed mode. These collectors are mostly tilted southwards at an angle of inclination ranging from 0° to 60° to the horizontal. Design has focused on the utilization of available local materials with some dryers that can be equipped with supplementary heating source or a storage of energy. Solar drying research among the African countries is very low generally and requires investment to boast it. Therefore, this review highlights solar dryers evaluated within the African region, including the quality of the final product, their efficiency, and prediction of its behavior using simulation and mathematical modeling. Pointing the area of future research and development is also emphasized.

ACS Style

Macmanus Ndukwu; L. Bennamoun; Fidelis Abam. Experience of Solar Drying in Africa: Presentation of Designs, Operations, and Models. Food Engineering Reviews 2018, 10, 211 -244.

AMA Style

Macmanus Ndukwu, L. Bennamoun, Fidelis Abam. Experience of Solar Drying in Africa: Presentation of Designs, Operations, and Models. Food Engineering Reviews. 2018; 10 (4):211-244.

Chicago/Turabian Style

Macmanus Ndukwu; L. Bennamoun; Fidelis Abam. 2018. "Experience of Solar Drying in Africa: Presentation of Designs, Operations, and Models." Food Engineering Reviews 10, no. 4: 211-244.

Journal article
Published: 09 August 2018 in International Journal of Refrigeration
Reads 0
Downloads 0

This experimental work studies the performance of varying concentrations of SiO2 nanoparticle in mineral oil lubricant using LPG refrigerant, as a retrofit to R134a in a domestic refrigeration system. The test rig is fitted with thermocouple K, pressure gauges and a watt-meter to monitor the suction, discharge, the condensing temperatures, pressures and power consumption in accordance with ISO 8187 recommendations. Performance parameters investigated included: pull down time, compressor power consumption and input, coefficient of performance and thermal conductivity and viscosity. Findings showed that all the selected charges of LPG refrigerant infused with varying concentrations of nano-lubricants, achieved equal values of -3°C (ISO 8187), or lower values of evaporator air temperatures at lower refrigerant charges, than the baseline R134a refrigerant. All the selected nano-lubricants based refrigerants resulted in improved Coefficient of Performance (COP) than R134a refrigerant, with COP values ranging from 2.05 with 50g charge of LPG using 0.4g/L nano-lubricant to 2.65 with 60g of LPG using 0.2g/L SiO2 based lubricant. Lower power input was recorded by the compressor for all the selected charges of SiO2-lubricant based LPG than R134a refrigerants, having 28.81W (with 60g charge of LPG using 0.2g/L) and 39.21W (with 100g charge of R134a refrigerant using pure compressor oil lubricant). In addition, at low concentration of nanoparticle in the lubricants based LPG refrigerant, reduction in power consumption of the compressor was observed, whereas higher concentration of nanoparticle in the lubricant, resulted in a rise in power consumption. Furthermore, thermal conductivity values were found to be low at the suction and discharge ends of the compressor for R134a using pure mineral oil lubricant, whereas the values were high for retrofit working fluid (pure LPG refrigerant, and LPG with varying concentrations of nano-lubricants), at the suction and discharge ends of the compressor.

ACS Style

Olayinka S. Ohunakin; Damola S. Adelekan; Jatinder Gill; Aderemi A. Atayero; Opemipo Atiba; Imhade P. Okokpujie; Fidelis Abam. Performance of a hydrocarbon driven domestic refrigerator based on varying concentration of SiO2 nano-lubricant. International Journal of Refrigeration 2018, 94, 59 -70.

AMA Style

Olayinka S. Ohunakin, Damola S. Adelekan, Jatinder Gill, Aderemi A. Atayero, Opemipo Atiba, Imhade P. Okokpujie, Fidelis Abam. Performance of a hydrocarbon driven domestic refrigerator based on varying concentration of SiO2 nano-lubricant. International Journal of Refrigeration. 2018; 94 ():59-70.

Chicago/Turabian Style

Olayinka S. Ohunakin; Damola S. Adelekan; Jatinder Gill; Aderemi A. Atayero; Opemipo Atiba; Imhade P. Okokpujie; Fidelis Abam. 2018. "Performance of a hydrocarbon driven domestic refrigerator based on varying concentration of SiO2 nano-lubricant." International Journal of Refrigeration 94, no. : 59-70.

Original paper
Published: 07 May 2018 in Waste and Biomass Valorization
Reads 0
Downloads 0

Utilization of evaporative cooling to condition rooms for increased productivity of farm animals is very common. The major challenge in adopting this technology in sub-Saharan Africa is the availability of cheap and effective cooling pads to provide the desired room condition. In this research, prediction of heat and mass transfer coefficient and evaporation losses of three agro based evaporative cooling pads based on mass density difference of the process fluid and binary diffusivity coefficient at the exit air temperature was established. The study was performed for wood charcoal, jut and palm fruit fiber as evaporative cooling pad materials. The dynamic performance of these three agro based cooling pads was also investigated in real time under a very fluid dry environment with a constantly intruding moist wind from southern Atlantic Ocean. The experimental results showed that mass transfer coefficient for the three products varied from 1.969 × 10−2 to 1.503 × 10−1 m/s depending on the product and the applied air flow rate. Similarly, the heat transfer coefficient ranged from 19.79 to 151.1 W/m2 K. Periodic variation in evaporative effectiveness was observed with highest value occurring at the lowest inlet air velocity of 1.13 m/s for jute fiber. Comparison of the modeling results between Halasz, and the indicative rule of thumb used by Baltimore Aircoil was favorable to Halasz model with a coefficient of variation ranging from 0 to 3.06 × 10−7 and a correlation coefficient of about 0.98. the second model has shown a deviation from experimental results that can reach 45% under particular conditions.

ACS Style

Macmanus Ndukwu; S. I. Manuwa; L. Bennamoun; O. J. Olukunle; Fidelis Abam. In-Situ Evolution of Heat and Mass Transfer Phenomena and Evaporative Water Losses of Three Agro-Waste Evaporative Cooling Pads: An Experimental and Modeling Study. Waste and Biomass Valorization 2018, 10, 3185 -3195.

AMA Style

Macmanus Ndukwu, S. I. Manuwa, L. Bennamoun, O. J. Olukunle, Fidelis Abam. In-Situ Evolution of Heat and Mass Transfer Phenomena and Evaporative Water Losses of Three Agro-Waste Evaporative Cooling Pads: An Experimental and Modeling Study. Waste and Biomass Valorization. 2018; 10 (10):3185-3195.

Chicago/Turabian Style

Macmanus Ndukwu; S. I. Manuwa; L. Bennamoun; O. J. Olukunle; Fidelis Abam. 2018. "In-Situ Evolution of Heat and Mass Transfer Phenomena and Evaporative Water Losses of Three Agro-Waste Evaporative Cooling Pads: An Experimental and Modeling Study." Waste and Biomass Valorization 10, no. 10: 3185-3195.

Journal article
Published: 03 May 2018 in Nigerian Journal of Technological Research
Reads 0
Downloads 0

An off wing fleet maintenance study of the CFM56-3B Turbofan engine that propels the Boeing 737-300 aircraft is presented. The engine performance and deteriorating behavior was modeled with a view to estimate the creep life consumption and operating severity. The predicted severity factor of each degradation was similar to the trend observed by the maintenance, repair and overhauling (MRO) with 0 - 3.1% difference. The combine degradation severity factor of the engine operating at both saline and desert mission areas was 6.4% and 7.5% respectively when compared with compressor fouling or turbine erosion cases. The creep life obtained was 2.5% lower. Combine degradation resulted in high severity factor of 5% emission development index (EDI) and the cost of complete replacement of a damaged blade was USD 256 per flight hour (FH). However, for the isolated cases of degradation, the severity factor was 3% EDI lower and the cost of refurbishing a damage blade was USD 81/FH. This indicates that a refurbishment program can be considered for CFM56-3B engines operating in condition of low severity and replacement program for engines operating in condition of high severity.Keywords: Turbofan engine, Severity factor, Degradation

ACS Style

Samuel O. Effiom; Fidelis I. Abam; Chukwuma H. Kadurumba; David Ebongue; Vincent C. Mmadubugwu. Off-wing fleet maintenance study of a CFM56-3B turbofan engine: the propulsive engine of Boeing 737-300 civil aircraft. Nigerian Journal of Technological Research 2018, 13, 72 .

AMA Style

Samuel O. Effiom, Fidelis I. Abam, Chukwuma H. Kadurumba, David Ebongue, Vincent C. Mmadubugwu. Off-wing fleet maintenance study of a CFM56-3B turbofan engine: the propulsive engine of Boeing 737-300 civil aircraft. Nigerian Journal of Technological Research. 2018; 13 (1):72.

Chicago/Turabian Style

Samuel O. Effiom; Fidelis I. Abam; Chukwuma H. Kadurumba; David Ebongue; Vincent C. Mmadubugwu. 2018. "Off-wing fleet maintenance study of a CFM56-3B turbofan engine: the propulsive engine of Boeing 737-300 civil aircraft." Nigerian Journal of Technological Research 13, no. 1: 72.

Original articles
Published: 12 February 2018 in Australian Journal of Mechanical Engineering
Reads 0
Downloads 0

The performance and thermo-sustainability indicators (TSI) of non-hybrid organic Rankine cycles (ORCs) are considered at varying evaporator pressure (EVP) and heat source temperature (HST). The ORCs structures include the ORC-basic, ORC-internal heat exchanger (ORC-IHE), ORC-turbine bleeding and ORC-turbine bleeding/regeneration. The TSI considered exergy efficiency, waste exergy ratio (WER), exergetic sustainability index (ESI) and environmental effect factor (EEF). The calculated overall exergy efficiency varies from 35.35 to 47.23 for evaporator pressure between 2 and 3 MPa and 49.02 to 52.71 for HST between 500 and 650 K. Additionally, WER, ESI and EEF were found to vary from 0.253 to 0.278, 1.15 to 1.87 and 0.547 to 0.82, respectively while ESI decreases for all variants of HST. The results indicate high ESI and low WER in ORC-IHE and the ORC-turbine bleeding /regeneration for all variations in EVP and HST.

ACS Style

Fidelis I. Abam; Ekwe B. Ekwe; Samuel O. Effiom; Christopher B. Afangideh. Performance and thermo-sustainability analysis of non-hybrid organic Rankine cycles (ORCs) at varying heat source and evaporator conditions. Australian Journal of Mechanical Engineering 2018, 1 -14.

AMA Style

Fidelis I. Abam, Ekwe B. Ekwe, Samuel O. Effiom, Christopher B. Afangideh. Performance and thermo-sustainability analysis of non-hybrid organic Rankine cycles (ORCs) at varying heat source and evaporator conditions. Australian Journal of Mechanical Engineering. 2018; ():1-14.

Chicago/Turabian Style

Fidelis I. Abam; Ekwe B. Ekwe; Samuel O. Effiom; Christopher B. Afangideh. 2018. "Performance and thermo-sustainability analysis of non-hybrid organic Rankine cycles (ORCs) at varying heat source and evaporator conditions." Australian Journal of Mechanical Engineering , no. : 1-14.