Updated on 2024/12/01

写真a

 
IBRAHIM, Nasiru Ishaq
 
Affiliation
Research Council (Research Organization), Sustainable Energy & Environmental Society Open Innovation Research Organization
Job title
Junior Researcher(Assistant Professor)
Degree
Doctor of Phylosophy, Mechanical Engineering ( Universiti Teknologi Malaysia )

Research Experience

  • 2024.01
    -
    Now

    Waseda University   Sustainable Energy & Environmental Society Open Innovation Research Organization   Assistant Profeesor (Junior Researcher)

  • 2020.09
    -
    2023.12

    King Fahd University of Petroleum & Minerals   Interdisciplinary Research Center for Renewable Energy and Power Systems (IRC-REPS)

  • 2014.01
    -
    2016.09

    King Fahd University of Petroleum & Minerals   Center of Research Excellence in Renewable Energy   Technical Research Assistant

Education Background

  • 2016.11
    -
    2020.09

    Universiti Teknologi Malaysia   Mechanical Engineering   Ph.D  

  • 2010.09
    -
    2014.01

    King Fahd University of Petroleum & Minerals   Mechanical Engineering   MSc  

  • 2002.06
    -
    2009.01

    Bayero University Kano   Mechanical Engineering   B.Eng.  

Research Areas

  • Earth resource engineering, Energy sciences   Thermal engineering, heat pumps, sustainable cooling and heating, energy efficiency, decarbonization

Research Interests

  • Sustainable energy systems

Awards

  • Highly Cited Paper Award

    2022.03   King Fahd University of Petroleum and Minerals  

  • Patent Recognition Award

    2019.03   King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia  

 

Papers

  • Offshore Wind Power Resource Assessment in the Gulf of North Suez

    Shafiqur Rehman, Kashif Irshad, Nasiru I. Ibrahim, Ali AlShaikhi, Mohamed A. Mohandes

    Sustainability (Switzerland)   15 ( 21 )  2023.11

     View Summary

    Growing population, industrialization, and power requirements are adversely affecting the environment through increased greenhouse gases resulting from fossil fuel burning. Global greenhouse gas mitigation targets have led nations to promote clean and self-renewable sources of energy to address this environmental issue. Offshore wind power resources are relatively more attractive due to high winds, less turbulence, minimal visualization effects, and no interaction of infrastructure. The present study aims at conducting an offshore wind power resource assessment (OWPRA) at some locations in the Gulf of North Suez. For this purpose, the long-term hourly mean wind speed (WS) and wind direction above mean sea level (AMSL), as well as temperature and pressure data near the surface, are used. The data is obtained from ERA5 (fifth generation global climate reanalysis) at six (L1–L6) chosen offshore locations. The data covers a period of 43 years, between 1979 and 2021. The WS and direction are provided at 100 m AMSL, while temperature and pressure are available near water-surface level. At the L1 to L6 locations, the log-term mean WS and wind power density (WPD) values are found to be 7.55 m/s and 370 W/m2, 6.37 m/s and 225 W/m2, 6.91 m/s and 281 W/m2, 5.48 m/s and 142 W/m2, 4.30 m/s and 77 W/m2, and 5.03 and 115 W/m2 and at 100 m AMSL, respectively. The higher magnitudes of monthly and annual windy site identifier indices (MWSI and AWSI) of 18.68 and 57.41 and 12.70 and 42.94 at the L1 and L3 sites, and generally lower values of wind variability indices, are indicative of a favorable winds source, which is also supported by higher magnitudes of mean WS, WPD, annual energy yields, plant capacity factors, and wind duration at these sites. The cost of energy for the worst and the best cases are estimated as 10.120 USD/kWh and 1.274 USD/kWh at the L5 and L1 sites, corresponding to wind turbines WT1 and WT4. Based on this analysis, sites L1, L3, and L2 are recommended for wind farm development in order of preference. The wind variability and windy site identifier indices introduced will help decision-makers in targeting potential windy sites with more confidence.

    DOI

  • A systematic thermodynamic performance assessment of a solar-driven double-effect absorption chiller integrated with absorption energy storage

    Nasiru I. Ibrahim, Shafiqur Rehman, Fahad A. Al-Sulaiman, Farid Nasir Ani

    Applied Thermal Engineering   221  2023.02

     View Summary

    Sensible heat storage in the form of hot water is usually applied to solar-driven cooling systems to increase their cooling coverage. The main limitation of sensible heat storage is high thermal losses. A double-effect absorption chiller is operating in a typical generating temperature range of 150–180 °C and has a better performance compared to the single-effect type. Due to the high operating temperature range of the chiller, this study suggests the integration of an absorption energy storage (AES) on a double-effect chiller based on H2O-LiBr solution and driven by parabolic trough solar collectors. This is because in AES, heat is stored in the form of chemical potential and the issue of heat loss is minimal. The paper presents a model of the integrated system and its performance evaluation considering the undesirable solution crystallization phenomena under various operating conditions. The results show that, under certain operating conditions, there is a high risk of solution crystallization in the chiller during the charging operation when the solution distribution ratio is below 50 %. Moreover, the results indicate that when a solution with an initial lithium mass fraction of around 55 % in the strong tank is considered, there is a tendency for crystal formation in the solution storage tank and at some locations within the chiller. There is a potential risk of solution crystallization in the solution storage tank and at some locations within the chiller cycle when a solution with an initial LiBr mass fraction of 55 % and an initial mass of 64,000 kg is considered. Considering the weather data of Dhahran, the best-operating conditions are obtained at an initial solution mass of 64,000 kg in the storage tank, initial solution LiBr mass fraction of 0.5, and solution distribution ratio of 55 %. At these and other conditions detailed in the paper, the highest energy storage density is about 136.8 kWh/m3, with an average cooling effect of 1700 kW, overall solar system COP, and exergy efficiency of 0.985 and 0.067 respectively, during a fourteen-hour operation. The findings in this study provide useful information to researchers on sizing the storage unit considering the appropriate initial conditions to avoid solution crystallization.

    DOI

  • Energetic performance analysis of a solar-driven hybrid ejector cooling and humidification-dehumidification desalination system

    Hamad A. Almahmoud, Fahad A. Al-Sulaiman, Nasiru I. Ibrahim, Ridha Ben Mansour, Yousif M. Alkhulaifi

    Energy   230  2021.09

     View Summary

    One technique for improving energy efficiency is combining two or more energy systems to form a hybrid one that utilizes a single energy source. The use of renewable energy, such as solar heat to power hybrid systems, is another advantage. This paper introduces a novel hybrid ejector cooling-desalination system driven by an evacuated tube solar collector. The ejector cooling cycle (ECC) is combined with a closed-air, open-water, water-heated humidification dehumidification (HDH) desalination system. A thermodynamic model of the hybrid system has been developed, validated, evaluated, and presented in this paper, considering different refrigerants for the ejector cycle. The results indicate that the hybrid system achieved an energy utilization factor (EUF) of 1.4 with R600 as the ECC refrigerant. This represents the highest value (about 4–27%) than the other selected refrigerants. Hence, R600 is selected as the best refrigerant for the hybrid system. A case study of the hybrid system has been presented, considering several cities in Saudi Arabia using solar energy as the only source of energy. Results indicate about 15% energy input saving by the hybrid system for the specified outputs for Qassim city.

    DOI

  • Economic analysis of a novel solar-assisted air conditioning system with integral absorption energy storage

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Shafiqur Rehman, Aminuddin Saat, Farid Nasir Ani

    Journal of Cleaner Production   291  2021.04

     View Summary

    The application of solar cooling systems is directly linked to the availability of solar radiation. Consequently, energy storage is important to achieve extended cooling coverage. This paper presents the economic performance evaluation of a novel solar-assisted absorption air conditioning system integrated with absorption energy storage (AES). The proposed solar-assisted air conditioning system consists of a parabolic trough solar collector (PTC), parallel-flow double-effect water-lithium bromide (H2O–LiBr) absorption chiller, and AES. In this paper, the economic feasibility of the system is evaluated based on the annuity method. The results indicate a payback period of about 5 years to recover the initial investment of the proposed system for a commercial building based on the weather conditions of the Eastern region of Saudi Arabia. The existing vapour-compression air conditioning system operating alone consumes more energy compared to that when supplemented with the solar-driven absorption chiller with AES. A maximum of 58% energy-saving is achieved from the integrated solar-assisted cooling system in July and August. Furthermore, a solar fraction of 63% is obtained from the integrated solar cooling system. Finally, the annual levelized cost of energy-savings of about 137,944 USD is achieved from the proposed cooling system.

    DOI

  • Performance and exergoeconomic assessment of a novel combined ejector cooling with humidification-dehumidification (HDH) desalination system

    Yousif M. Alkhulaifi, Emad Baata, Fahad A. Al-Sulaiman, Nasiru I. Ibrahim, Ridha Ben-Mansour

    Desalination   500  2021.03

     View Summary

    In recent decades, innovations in desalinating water and cooling have led to improving the living standards and well-being. The significance of these technologies provides a path for synergistic integration. In the present study, a novel combined ejector cooling with a humidification-dehumidification desalination system for cogeneration of a considerable amount of cooling and water was thoroughly studied in two configurations: solar-driven (system A) and waste heat-driven configurations (system B). The mathematical models were based on the first and second laws of thermodynamics and exergoeconomic relations to predict the performance and economic feasibility of the proposed systems. The studies were conducted under variation of the generator, condenser, and evaporator temperatures, and solar irradiance intensities. Many parameters were studied, including freshwater production, cooling capacity, COP, GOR, exergy destruction, and product costs. The freshwater and cooling costs for system A were 24.61 US$/m3 and 0.01544 US$/kWh, whereas, for system B, they were 3.84 US$/m3 and 0.001677 US$/kWh. However, the cost of the above products from system B can be as low as 2.39 US$/m3 and 0.001670 US$/kWh, respectively. It was concluded that the 24-hour operation and replacement of solar collectors with free waste heat recovery resulted in drastically reducing the cost of the products.

    DOI

  • Thermodynamic performance evaluation of a hybrid ejector cooling and humidification-dehumidification desalination system

    Hamad A. Al-Mahmoud, Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Syed M. Zubair

    Energy Conversion and Management   225  2020.12

     View Summary

    Energy consumption by cooling and desalination systems is huge and increasing with growing demand. The integration of two or more energy systems to form a hybrid system and work on a single energy source is one of the strategies for better energy utilization. This paper introduces a novel hybrid cooling-desalination system. The cooling unit is based on the ejector refrigeration cycle (ERC) and combined with water-heated humidification dehumidification (HDH) desalination cycle to make the hybrid system. A validated model of the hybrid system is developed and evaluated using the Engineering Equation Solver (EES) software. The basic ERC is analyzed with R134a as the refrigerant at different operating temperatures. The results show that the increase in the generator temperature improved the entrainment ratio (w) and the coefficient of performance (COP). The COP and entrainment ratio also increases with the increase in evaporator temperature. The increase in the condenser temperature resulted in a decrease in COP and entrainment ratio. The gain output ratio (GOR) of the HDH system is improved by 20%. This is due to the increase in the minimum temperature of the HDH system by 15 °C as a result of the hybrid configuration. This led to a 17% enhancement on the overall energy utilization factor.

    DOI

  • Charging and discharging characteristics of absorption energy storage integrated with a solar driven double-effect absorption chiller for air conditioning applications

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Aminuddin Saat, Shafiqur Rehman, Farid Nasir Ani

    Journal of Energy Storage   29  2020.06

     View Summary

    The operation of solar driven air conditioning systems is limited to the availability of solar radiation. Consequently, to achieve extended cooling period, energy storage is necessary. This study presents performance evaluation and charging and discharging characteristics of an absorption energy storage coupled with solar driven double-effect water-lithium bromide (H2O-LiBr) absorption system through thermodynamic modeling and simulation. The absorption energy storage stores the solar heat in the form of chemical energy during the day and discharges later for cooling application. The integrated system achieved effective cooling for about fourteen hours on daily basis. The results indicate an average coefficient of performance (COP) of 1.35 for the integrated absorption chiller-storage unit and exergy efficiency of 25%. Furthermore, the overall COP of the integrated solar cooling system is 0.99 and the overall exergy efficiency is 6.8%, while the energy storage density for typical climatic conditions of Dhahran, Saudi Arabia is found to be 444.3 MJ/m3. The energy storage density obtained from the integrated solar driven H2O-LiBr double-effect absorption system is found to be higher by 13–54% compared to other integrated systems based on single-effect configuration.

    DOI

  • A detailed parametric study of a solar driven double-effect absorption chiller under various solar radiation data

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Farid Nasir Ani

    Journal of Cleaner Production   251  2020.04

     View Summary

    This article presents simulation results of a solar cooling system that consists of a parallel-flow double-effect water-lithium bromide absorption chiller and parabolic trough solar collector. Parametric study of the cooling system is carried out considering a reference double-effect absorption chiller from Broad Company with nominal cooling capacity of 1163 kW. The aim for the analysis is to properly size the solar collector field and study the interaction of different operating conditions and parameters on the operation and performance of the system. Based on the operational constrains of the reference chiller, such as the minimum chilled water temperature and the cooling power, a solar collector field of 1350 m2 (1.16 m2/kW) is obtained from the range of 800–1800 m2. The reference system is then optimized where the exergy efficiency (second law efficiency) is maximized considering the flow rates of the external working fluid and solution distribution ratio of the parallel-flow double-effect absorption chiller as the decision variables. The system optimization is performed considering the risk of solution crystallization at various locations within the chiller. The optimum parameters together with other operating conditions are normalized per unit chiller nominal cooling capacity so that these values can be applied to other similar system configurations with different chiller nominal capacities. The reference system is simulated at optimum condition using a typical day climate data of Kuala Lumpur, Malaysia. The system achieved cooling effect in the range of 798–1223 kW under solar radiation levels of 600–944 W/m2. The procedure presented in this paper can be applied in sizing the solar collector field and evaluating the performance of similar systems under various climatic conditions having minimum solar radiation around 500 W/m2.

    DOI

  • Energetic Performance Optimization of a H2O-LiBr Absorption Chiller Powered by Evacuated Tube Solar Collector

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Farid Nasir Ani

    Renewable Energy and Sustainable Buildings     363 - 377  2020

    DOI

  • Performance and cost assessment of a solar HDH desalination system integrated with thermal storage: A case study

    M. Ifras Zubair, Fahad A. Al-Sulaiman, Mohammed A. Antar, S. Dini, Nasiru I. Ibrahim

    Desalination and Water Treatment   173   86 - 104  2020.01

     View Summary

    Solar desalination systems often have limited operating hours and their operation is significantly affected by the variation of solar radiation intensity. A model of a humidification–dehumidification (HDH) desalination system integrated with evacuated tube solar collectors and thermal storage is developed and validated against available data in the literature. Operating parameters such as the maximum temperature of water heater and the mass flow rate ratio of the HDH component are optimized. The thermal storage unit consists of separate hot and cold-water storage tanks, which allow control of the water temperature leaving the storage unit. Furthermore, performance of the system for six different geographical locations in Saudi Arabia, namely Riyadh, Jeddah, Dhahran, Qassim, Sharurah, and Tabuk, is studied. The system is evaluated for four different scenarios as follows: (i) 24-h operation; (ii) with the ideal flow rate; (iii) with the average flow rate; and (iv) with the maximum flow rate. The effect of flow rate on the number of operating hours and the rate of freshwater production is also evaluated. The maximum freshwater production is 9.346 L/h and the minimum is 3.01 L/h. For a service life of 20 years, the cost of freshwater produced varies from 0.021 to 0.034 $/L considering interest rate of 2%.

    DOI

  • Carbon nanotube nanofluid in enhancing the efficiency of evacuated tube solar collector

    I. M. Mahbubul, Mohammed Mumtaz A. Khan, Nasiru I. Ibrahim, Hafiz Muhammad Ali, Fahad A. Al-Sulaiman, R. Saidur

    Renewable Energy   121   36 - 44  2018.06

     View Summary

    The use of solar thermal collectors is one of the promising options for heating and/or cooling due to the green nature (pollution free) and abundance of the solar energy in many parts of the world. Improvement of thermal performance of solar collectors is important for better energy conversion. In this regard, many studies reported in literature tried to modify geometry of the collectors. On the other hand, nanofluids as heat transfer fluids could be a promising option for the efficiency enhancement of solar collectors. In this study, heating performance of an evacuated tube solar collector system initially operated with water is considered for improvement using nanofluid. The collector (about 20 kW heating capacity) is a part of an absorption cooling system. The aim of the present study is to analyze the effect of Single Walled Carbon Nanotube–water nanofluid on the collector performance. Thermal efficiency improvement is assessed based on comparative analyses between collector working with ordinary water and that with nanofluid. The results indicate that up to 56.7% and 66% of efficiencies are observed when the collector is operated with water and 0.2 vol% nanofluid, respectively. Therefore, nanofluids are promising to enhance the efficiencies of solar collectors.

    DOI

  • Performance enhancement of a vapor compression system by condensate

    Abdulghani A. Al-Farayedhi, Nasiru I. Ibrahim, Palanichamy Gandhidasan

    Science and Technology for the Built Environment   23 ( 5 ) 748 - 760  2017.07

     View Summary

    Air-conditioning systems consume large amount of energy and generate considerable amount of condensate when operated in hot and humid climates. This study considers utilizing the generated condensate to pre-cool the air entering evaporators to improve systems performance. Experimental and analytical investigations are carried out by using an air-conditioning system of 4.75 kW (16207 BTU/h) cooling capacity incorporated with an air pre-cooler and a condensate tank that acts as a thermal storage. During the pre-cooling-on period, the air inlet temperature of the evaporator is decreased by 5.7°C (10.3°F) and the compressor power consumption is reduced by 5.1% because of the decrease in discharge pressure. The coefficient of performance increases by 30.7% and second-law efficiency by 24.2%. The air pre-cooling is practical for 4–5 hours daily during the daytime if a 450–1000 kg of condensate cold thermal storage is employed. The deviation is 6.7% between the analytical and experimental results.

    DOI

  • Recent Developments in Liquid Desiccant-Based Cooling Systems

    M. Mujahid Rafique, P. Gandhidasan, Nasiru I. Ibrahim, Haitham M. Bahaidarah

    Encyclopedia of Sustainable Technologies     441 - 453  2017.07

     View Summary

    The conventional vapor compression air conditioning systems remove moisture from the air by cooling to a very low temperature. This dehumidified air is then reheated to an appropriate supply temperature for occupants comfort. These two processes of excessive cooling and reheating of process air remarkably increase the air conditioning load. To avoid the excessive waste of energy an alternative way to achieve desired moisture reduction is the use of liquid desiccant dehumidification system in which a desiccant material absorbs moisture from the humid air. Thermal energy is used to regenerate the desiccant material and cycle continues. A good desiccant should have better moisture absorption capability and lower temperature of regeneration. Different types of new desiccant materials with high dehumidification performance have been proposed in past few years. These materials have the potential to improve the performance of liquid desiccant cooling systems because of lower heat input required for regeneration. In this article, liquid desiccant cooling systems have been discussed from variety of aspects including the need of liquid desiccant technology as an alternative way of cooling, working of liquid desiccant cycle, as well as developments of this technology. The research indicated that the technology of liquid desiccant cooling has a great potential of energy saving and providing human thermal comfort conditions in hot and humid climatic conditions with the utilization of alternative energy resources.

    DOI

  • Performance and cost assessment of solar driven humidification dehumidification desalination system

    M. Ifras Zubair, Fahad A. Al-Sulaiman, M. A. Antar, Salem A. Al-Dini, Nasiru I. Ibrahim

    Energy Conversion and Management   132   28 - 39  2017.01

     View Summary

    A humidification-dehumidification (HDH) desalination system integrated with solar evacuated tubes was optimized. Then, the optimized system was assessed for the operation in different geographical locations, and the rate of freshwater production and cost per liter were determined in each location. The system design proposed in this paper uses a heat pipe design evacuated tube collector, which performs significantly better based on cost. An HDH desalination system with a closed-air/open-water loop, connected to the collector, was evaluated to determine the optimum operating parameters and the system performance during daytime (from 8 am to 3 pm), as well as the average day of each month for an entire year. The impact of the effectiveness of the humidifier and the dehumidifier, as well as, the number of collectors, were also studied. The analyses were performed for Dhahran, Jeddah, Riyadh, Sharurah, Qassim, and Tabuk to determine the effects of varying the geographical location. Sharurah has the highest calculated productivity of freshwater and Dhahran has the lowest at 19,445 and 16,430 L, respectively. To have a comprehensive study of the system proposed, a cost analysis was also performed to determine the feasibility of the system and the cost of water production. Results show that the price varied from $0.032 to $0.038 per liter for the locations evaluated.

    DOI

  • Experimental investigation of a vapor compression system with condenser air pre-cooling by condensate

    Nasiru I. Ibrahim, Abdulghani A. Al-Farayedhi, P. Gandhidasan

    Applied Thermal Engineering   110   1255 - 1263  2017.01

     View Summary

    Air conditioning systems contribute to the largest share of energy consumption in building sector. On the other hand, the systems produce reasonable amount of condensate, especially when operating in humid climates. The aim of this study is to minimize the energy consumption and improve the performance of air conditioning systems utilizing condensate. Experimental investigation has been carried out to improve the performance of an air-cooled vapor compression system by pre-cooling air entering the condenser using condensate. A pre-cooler is incorporated on a 1.5 ton-cooling capacity split-type air conditioning system to lower the air temperature entering the condenser sensibly. Performances of the air conditioning system with and without air pre-cooling are compared and reported in this paper. The results show that pre-cooling the air by about 4 °C before entering the condenser lowers the compressor discharge pressure. The decrease in the discharge pressure resulted in the decrease in compressor power consumption by 6.1% and the cooling effect of the system is enhanced. The combined effect of the increase in the cooling effect and decrease in compressor power resulted in an increase in the coefficient of performance (COP) and second law efficiency of the system by about 21.4 and 20.5%, respectively.

    DOI

  • Experimental testing of the performance of a solar absorption cooling system assisted with ice-storage for an office space

    Nasiru I. Ibrahim, Mohammed Mumtaz A. Khan, I. M. Mahbubul, R. Saidur, Fahad A. Al-Sulaiman

    Energy Conversion and Management   148   1399 - 1408  2017

     View Summary

    Energy storage plays a vital role in shifting cooling energy load from period of peak demand to that of low demand. This paper reports performance data of an ice-storage unit in solar absorption cooling system for cooling an office space. The cooling system consists of ammonia-water absorption chiller, evacuated tube solar collectors and ice-storage. Experiments were carried out on two consecutive days in each of the month of March and October in Dhahran, Saudi Arabia. The ice-storage unit was charged on the first day and the cool energy discharged on the other day. The results showed average coefficient of performance (COP) of the chiller during charging as 0.43 and 0.47 for the months of March and October, respectively. The results also indicate that the ice-storage can provide a backup time of about 5–6 h, which is sufficient to cool the given space during the early hours of chiller warm-up.

    DOI

  • Performance characteristics of a solar driven lithium bromide-water absorption chiller integrated with absorption energy storage

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Farid Nasir Ani

    Energy Conversion and Management   150   188 - 200  2017

     View Summary

    The use of solar–assisted absorption chiller for space cooling is limited to availability of solar radiation; hence, energy storage is very crucial in order to achieve extended hours of cooling operation. In this study, operational and performance characteristics of a solar driven lithium bromide-water absorption chiller integrated with absorption energy storage of the same working fluid are investigated. The integrated system simultaneously provides cooling and charging of the absorption energy storage during the hours of solar radiation. Simulation of the integrated system is carried out based on first law of thermodynamics. Effects of weather variables such as solar radiation and the influence of coupling absorption energy storage with an absorption chiller are investigated. The results indicate that cooling effect of the chiller varies with the variation of solar radiation, with maximum value of 20 kW for a collector area (Ac) of 96 m2 on a typical day in July, Dhahran, Saudi Arabia. The cooling COP of the integrated system during cooling/charging and discharging is found to be 0.69 and the energy storage density of the absorption energy storage is 119.6 kWh/m3. Furthermore, the operational characteristics of the proposed system showed that the internal operating parameters of the integrated chiller-absorption energy system such as solution temperatures and pressures are within reasonable levels. Hence, this indicates the possibility of integrating the absorption energy storage with absorption chiller.

    DOI

  • Performance assessment of water production from solar cooling system in humid climate

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, R. Saidur

    Energy Conversion and Management   127   647 - 655  2016.11

     View Summary

    This study aims to investigate water extraction process from a solar cooling system using a vapor absorption chiller under variable fresh air ratios. The system consists of an evacuated tube solar collector, lithium bromide absorption chiller and a fan coil unit (FCU). A parametric study is carried out to investigate the effects of flow rate of the fluid in the collector, solar insolation, fresh air volume ratio, temperature and humidity on the system performance and rate of water production. The operating conditions for the best performance are identified in this work. The results showed maximum collector efficiency of 0.66 at an optimum flow rate of the collector fluid of 0.3 kg/s at Ac = 28 m2, Tf = 45 °C, I = 800 W/m2 and R = 50%. For the same conditions, useful energy to the generator was found to be 14.8 kW and water production rate was 8 L/h. Using the climate data of a typical day of August for Dhahran, Saudi Arabia, the findings indicated that the chiller COP and water production rate, respectively, reached maximum (0.73 and 6.6 L/h) at noon when the incident solar flux is peak (935 W/m2) for 45% fresh air volume ratio.

    DOI

  • Performance assessment of a solar powered ammonia–water absorption refrigeration system with storage units

    Mohammed Mumtaz A. Khan, Nasiru I. Ibrahim, R. Saidur, I. M. Mahbubul, Fahad A. Al-Sulaiman

    Energy Conversion and Management   126   316 - 328  2016.10

     View Summary

    Solar thermal energy is one of the viable options for space cooling in the quest of greener environment and energy efficiency. The major challenge in actualizing the use of solar energy to drive cooling systems such as absorption chillers is its intermittent nature, thereby not able to cover significantly the period of cooling demand in most situations. In order to achieve continuous cooling energy supply from solar driven absorption chillers, the present study considered two alternative storage units in the form of chilled water and ice, integrated to the main chiller installed in Dhahran, Saudi Arabia. The system is designed to allow different operational modes in accordance with the cooling demands. The system is tested experimentally where the storage units are used alternatively and the results are presented. A mean chiller COP for cooling the space and chilling the water was found to be 0.8 whereas it was 1.3 for only making ice. Maximum COP (0.8) was found at Tgen = 120 °C at an average condenser and evaporator temperatures of 34.5 °C and −2.2 °C, respectively.

    DOI

  • Thermodynamic analysis of a mini hybrid solar driven cooling-desalination system

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Saidur Rahman

    ASME 2016 10th International Conference on Energy Sustainability, ES 2016, collocated with the ASME 2016 Power Conference and the ASME 2016 14th International Conference on Fuel Cell Science, Engineering and Technology   1  2016

     View Summary

    Water desalination and air conditioning consumes huge amount of energy that mostly come from fossil fuels, which produces harmful emissions detrimental to the environment. This work is concerned with the use of a new hybrid cooling and water desalination system driven by solar thermal energy. The system primarily consists of an evacuated tube solar collector, LiBr absorption chiller, and a humidification-dehumidification (HDH) unit. Seawater is used to cool the condenser and absorber of the chiller as well as the condenser of the HDH unit. The heat rejected by the absorber is used to drive the HDH unit. Thermodynamic model of the system has been formulated and simulated using engineering equation solver (EES) software. The results show that the coefficient of performance (COP) of the chiller nearly remain constant with increase in seawater temperature at the absorber inlet. The average COP of the chiller is found to be 0.76. The hybrid system efficiency increases with increase in the seawater temperature mainly due the effect of latent heat of water condensation. The rate of fresh water production increases with increase in the seawater inlet temperature. This resulted in a higher outlet temperature at the absorber exit, leading to a higher energy input to the HDH unit. Gained output ratio (GOR) increases with increase in seawater temperature. This is due to the direct proportionality of the GOR to the amount of fresh water produced. The results also revealed that increasing the flow rate of seawater causes the decrease in the fresh water production due to the corresponding decrease in the temperature of the seawater.

    DOI

  • Experimental and numerical study on non-concentrating and symmetric unglazed compound parabolic photovoltaic concentration systems

    Haitham M. Bahaidarah, Bilal Tanweer, P. Gandhidasan, Nasiru Ibrahim, Shafiqur Rehman

    Applied Energy   136   527 - 536  2014.12

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    Comparative study on flat photovoltaic (PV) string and symmetric compound parabolic concentrator (CPC) photovoltaic system has been presented in this paper. Two flat PV strings and two unglazed PV-CPC systems are considered. The cells of each of the flat PV and PV-CPC strings are subjected to cooling to reduce temperature. The performance of the two configurations with and without cooling is evaluated numerically and experimentally. The numerical models for the flat PV string and the PV-CPC systems are solved using Engineering Equation Solver (EES) software and the concentration ratio of the CPC system is considered as 2.3X. Absorbed energy is calculated with and without cooling for the PV-CPC and flat PV systems. The absorbed energy is used to solve the energy balance equations on different nodes of the system from which the cell temperature was determined. The results showed that the maximum power output of the flat PV string with cooling was approximately 21. W which gives about 49% more than the power obtained without cooling. The maximum power output of the PV-CPC system with cooling was approximately 34. W which is about twice of the power obtained in the absence of cooling. It was found that the power output of the PV-CPC system is higher than that of the flat PV string with and without cooling by 39% and 23% respectively. Comparison of the numerical results with experimental data showed good agreement for the two configurations. The maximum percentage differences between the numerical and experimental power output for the flat PV with and without cooling are 5% and 7%, respectively. While those of the PV-CPC system with and without cooling are 9% and 11%, respectively.

    DOI

  • Condensate as a water source from vapor compression systems in hot and humid regions

    Abdulghani A. Al-Farayedhi, Nasiru I. Ibrahim, P. Gandhidasan

    Desalination   349   60 - 67  2014.09

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    Water is one of the basic necessities in life and its preservation is essential, particularly in hot and humid regions. Air conditioning systems operating in these regions usually produce a considerable amount of condensate. In this paper, analytical and experimental investigations in determining the condensate from a vapor compression air conditioning system as an additional water source are presented. A split type air conditioning system (1.5. tons) located in Dhahran, Saudi Arabia, where the dry bulb temperatures and relative humidity range from 25 to 50. °C and from 15 to 90%, respectively, is used for the study during summer months. Based on the hourly data, the monthly condensate yields during June, July, August and September are 1.26, 1.29, 2.50 and 2.33. kg/ton per CDD, respectively. The condensate is dominantly affected by the air humidity and temperature. The variation pattern of the condensate extraction is similar to that of the relative humidity. The collected condensate can be used as an additional water source. The chemical analysis of the condensate indicates that the water can be used for human consumption. The analytical model predictions of the condensate correlate well with the experimental data with a correlation factor of more than 90%. © 2014 Elsevier B.V.

    DOI

  • A novel technique for reducing cooling load of an air conditioning system operating in hot and humid climates

    Abdulghani A. Al-Farayedhi, Nasiru I. Ibrahim, P. Gandhidasan

    ASME 2013 Heat Transfer Summer Conf. Collocated with the ASME 2013 7th Int. Conf. on Energy Sustainability and the ASME 2013 11th Int. Conf. on Fuel Cell Science, Engineering and Technology, HT 2013   2  2013

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    Cooling load is the energy needed to be removed from a space by a cooling system to provide the desired level of comfort. Large space load requires high energy from the cooling system. A new technique of reducing the cooling load using condensate to pre-cool air stream entering the evaporator of a vapor compression air-conditioning system is presented in this paper. In a cooling process, water vapor condensation normally occurs when the evaporator coil surface temperature becomes lower than the dew point temperature of the humid air entering the evaporator. The cooling process results in appreciable amount of condensate in climatic conditions with high relative humidity and temperature such as those in Dhahran, Saudi Arabia. The rate of condensate yield is calculated using actual climate data of three typical summer days of Dhahran area for the months of June, July and August. These months are the most humid and hottest during the year. Each month is represented by a typical day determined by the average of the three hottest and humid days during the same months of the past three years. It is found that the condensate obtained during night time is more than the day time because of the high relative humidity at night. The results indicate that the cooling load can be reduced up to 10 % when the air entering the evaporator is pre-cooled by 4 °C using the condensate. In addition, the daily condensate yields from the evaporator coil in June, July and August are 1.27, 0.92 and 1.31 kg/kW-CDD, respectively. Copyright © 2013 by ASME.

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Misc

  • Solar cooling with absorption chillers, thermal energy storage, and control strategies: A review

    Nasiru I. Ibrahim, Azzedine Yahiaoui, Jamilu Adamu Garkuwa, Ridha Ben Mansour, Shafiqur Rehman

    Journal of Energy Storage   97  2024.09

    Book review, literature introduction, etc.  

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    Solar cooling technology is a potential solution for air conditioning and thermal comfort in buildings. However, the intermittent nature of solar energy is a significant challenge for the widespread adoption of this technology. In order to overcome this challenge, energy storage systems and new control strategies are needed to smooth the fluctuations of solar energy and ensure consistent cooling output. However, integrating energy storage with solar cooling systems and their interaction with load requires a considerable initial investment. This paper reviews the methods for integrating solar absorption cooling systems with thermal energy storage and discusses control strategies for optimal performance. The paper provides valuable insights into the current status and future research directions in this area.

    DOI

  • Challenges of the application of PCMs to achieve zero energy buildings under hot weather conditions: A review

    Md Hasan Zahir, Kashif Irshad, Md Shafiullah, Nasiru I. Ibrahim, A. K.M. Kausarul Islam, Khaled Own Mohaisen, Fahad A.Al Sulaiman

    Journal of Energy Storage   64  2023.08

    Book review, literature introduction, etc.  

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    With the global increase in population and temperature, cooling demand has increased tremendously in the building sector, especially in the GCC and African and South Asian countries where temperature can reach 50 °C from mid-May to August. Thermal performance of buildings can be effectively improved by using thermal energy storage (TES) systems based on phase change materials (PCMs). As PCMs melt during the daytime and solidify at nighttime, they can prevent rooms from overheating during daytime in hot months and may also reduce the need for heating during nighttime in the winter. This paper discusses the use of TES for the storage of sensible heat, latent heat, and thermochemical energy in buildings. Sustainable heating and cooling in buildings employing TES can be achieved with passive building envelope systems, active systems containing PCMs, sorption systems, and seasonal storage systems. This review presents results obtained in earlier studies on the incorporation of PCMs in building materials, the problems associated with the selection of PCMs, and various methods used to encapsulate PCMs for space heating and cooling applications. Furthermore, this article provides an outline of a range of PCM applications in buildings for decreasing the cooling loads under hot atmosphere conditions, and the parameters influencing the productive and viable use of PCMs under hot weather conditions. Several shortcomings in the application of PCMs, mostly due to the extreme summer weather conditions preventing the PCM from completely solidifying at night and thereby decreasing its effectiveness during the day, were identified. Although sunlight is abundant in the Middle East, the use of solar energy in conjunction with PCM technology for temperature control in buildings is rare. One of the main reasons for the status quo is the small temperature difference between day and night. Hence, the selection of a suitable PCM is crucial and challenging for this type of a hot atmosphere. As a consequence, the current study will fill a scientific gap concerning PCM usage in this vital hot temperature range. Under such extreme environmental conditions, thermal conductivity, density, and the specific heat of the insulation affect the heat flow. Finally, future research opportunities were explored and shortcomings of the technology as of today were discussed.

    DOI

  • Evaluation of solar collector designs with integrated latent heat thermal energy storage: A review

    Mohammed Mumtaz A. Khan, Nasiru I. Ibrahim, I. M. Mahbubul, Hafiz Muhammad. Ali, R. Saidur, Fahad A. Al-Sulaiman

    Solar Energy   166   334 - 350  2018.05

    Book review, literature introduction, etc.  

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    Solar collectors have been rigorously modified over the years to better serve the thermal needs of the era. Various design innovations have paved their way to invent new ways of gaining more solar energy in the form of useful heat. Few of these approaches have been commercialized and others have taught lessons. New technological advancements, like phase change materials (PCM), and their integration with solar collectors produced better results in recent years. Hence, various methods of integrating PCM inside the collector cavity were investigated. This review studies innovative concepts of integrating PCMs in flat plate (water/air), evacuated tube, and photovoltaic/thermal solar collectors. Flat plate collectors for water and air heating have been extensively studied. Uses of nano-composite PCM in solar collectors are also compiled. It was observed that maximizing the contact surface area between the PCM and the absorber plate significantly enhances the outlet temperatures. General trends, proportionalities and noteworthy observations are also discussed for each type.

    DOI

  • Solar absorption systems with integrated absorption energy storage–A review

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Farid Nasir Ani

    Renewable and Sustainable Energy Reviews   82   1602 - 1610  2018.02

    Book review, literature introduction, etc.  

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    Solar driven absorption systems are becoming more tractive and common in air conditioning industry. However, the issue of intermittency of the solar energy remains the critical concern in real applications. Hence, energy storage is inevitable to bridge the energy demand and intermittency gap. Among the existing thermal energy storage options, sensible heat storage is the most widely adopted in solar thermal applications. Research interest on absorption energy storage is increasing recently owing to low heat loss and high-energy storage capability. This paper presents a specific review on solar absorption energy storage and its integration with conventional absorption chillers. Specific future research directions on the subject are highlighted in the paper. These include economic viability of the absorption energy storage, improved design of heat exchangers and considering the concept of absorption energy storage as an option for shifting solar thermal energy collected during the peak day-hours to the off peak night-hours for air conditioning, among others.

    DOI

  • A review on current status and challenges of inorganic phase change materials for thermal energy storage systems

    Shamseldin A. Mohamed, Fahad A. Al-Sulaiman, Nasiru I. Ibrahim, Md Hasan Zahir, Amir Al-Ahmed, R. Saidur, B. S. Yılbaş, A. Z. Sahin

    Renewable and Sustainable Energy Reviews   70   1072 - 1089  2017

    Book review, literature introduction, etc.  

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    Latent heat energy storage system is one of the promising solutions for efficient way of storing excess thermal energy during low consumption periods. One of the challenges for latent heat storage systems is the proper selection of the phase change materials (PCMs) for the targeted applications. As compared to organic PCMs, inorganic PCMs have some drawbacks, such as corrosion potential and phase separation; however, there are available techniques to overcome or minimize these drawbacks. On the other hand, inorganic PCMs are found to have higher thermal conductivity and storage capacity over organic PCMs. As a result inorganic PCMs have a great potential in thermal energy storage field, especially in medium to high temperature applications where organic PCMs are not a viable option. In this study, a detailed review of research outcomes and recent technological advancements in the field of inorganic phase change materials is presented while focusing on providing solutions to the associated disadvantages of this class of PCMs. Long term stability, thermal cycling performance, and heat transfer enhancements are also discussed in the context of this review.

    DOI

  • Heat transfer enhancement of phase change materials for thermal energy storage applications: A critical review

    Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Saidur Rahman, Bekir S. Yilbas, Ahmet Z. Sahin

    Renewable and Sustainable Energy Reviews   74   26 - 50  2017

    Book review, literature introduction, etc.  

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    This paper presents a state-of-the-art review on various techniques of heat transfer enhancement in latent heat thermal energy storage (LHTES) systems. Heat transfer enhancement in LHTES systems can be achieved through either geometric configuration and/or thermal conductivity enhancement. The use of extended surfaces such as fins or heat pipes is a common technique for heat transfer enhancement in LHTES systems and therefore, reviewed in details in this paper. Next, we studied the thermal conductivity enhancement techniques, which include the use of porous materials, nanoparticles with high thermal conductivity, and low-density materials. Finally, studies involving combined techniques for heat transfer enhancement are reviewed in the paper. The paper discusses research gaps in the methods of heat transfer enhancement for LHTES systems and proposed some recommendations.

    DOI

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