Professor JO DARKWA's Outputs (68)

Experimental Investigation on Compressive Strength, Ultrasonic Characteristic and Cracks Distribution of Granite Rock Irradiated by a Moving Laser Beam (2022)
Journal Article
Kuang, L., Sun, L., Yu, D., Wang, Y., Chu, Z., & Darkwa, J. (2022). Experimental Investigation on Compressive Strength, Ultrasonic Characteristic and Cracks Distribution of Granite Rock Irradiated by a Moving Laser Beam. Applied Sciences, 12(20), Article 10681. https://doi.org/10.3390/app122010681

Efficient fracturing is the key issue for the exploitation of geothermal energy in a Hot Dry Rock reservoir. By using the laser irradiation cracking method, this study investigates the changes in uniaxial compressive strength, ultrasonic characterist... Read More about Experimental Investigation on Compressive Strength, Ultrasonic Characteristic and Cracks Distribution of Granite Rock Irradiated by a Moving Laser Beam.

Machine Learning and Deep Learning Methods for Enhancing Building Energy Efficiency and Indoor Environmental Quality – A Review (2022)
Journal Article
Tien, P. W., Wei, S., Darkwa, J., Wood, C., & Calautit, J. K. (2022). Machine Learning and Deep Learning Methods for Enhancing Building Energy Efficiency and Indoor Environmental Quality – A Review. Energy and AI, 10, Article 100198. https://doi.org/10.1016/j.egyai.2022.100198

The built environment sector is responsible for almost one-third of the world's final energy consumption. Hence, seeking plausible solutions to minimise building energy demands and mitigate adverse environmental impacts is necessary. Artificial intel... Read More about Machine Learning and Deep Learning Methods for Enhancing Building Energy Efficiency and Indoor Environmental Quality – A Review.

Enhancing the detection performance of a vision-based occupancy detector for buildings (2022)
Journal Article
Tien, P. W., Wei, S., Chow, T. W., Darkwa, J., Wood, C., & Calautit, J. K. (2023). Enhancing the detection performance of a vision-based occupancy detector for buildings. Proceedings of the ICE - Engineering Sustainability, 176(6), 301-314. https://doi.org/10.1680/jensu.22.00013

Occupant behaviour is one of the key parameters that significantly impact the operation of heating, ventilation and air-conditioning (HVAC) systems and the energy performance of buildings. Detailed occupancy information can improve HVAC operation and... Read More about Enhancing the detection performance of a vision-based occupancy detector for buildings.

Evaluating urban heat island mitigation strategies for a subtropical city centre (a case study in Osaka, Japan) (2022)
Journal Article
Zheng, T., Qu, K., Darkwa, J., & Calautit, J. K. (2022). Evaluating urban heat island mitigation strategies for a subtropical city centre (a case study in Osaka, Japan). Energy, 250, Article 123721. https://doi.org/10.1016/j.energy.2022.123721

Urban heat island (UHI) effects were first observed in London in the 19th century. The urban heat island is identified by developing higher temperatures in urban areas than the surrounding rural areas that directly surround them. However, there are s... Read More about Evaluating urban heat island mitigation strategies for a subtropical city centre (a case study in Osaka, Japan).

The microencapsulation, thermal enhancement, and applications of medium and high-melting temperature phase change materials: A review (2022)
Journal Article
Sinaga, R., Darkwa, J., Omer, S. A., & Worall, M. (2022). The microencapsulation, thermal enhancement, and applications of medium and high-melting temperature phase change materials: A review. International Journal of Energy Research, 46(8), 10259-10300. https://doi.org/10.1002/er.7860

Microencapsulated phase change materials (MEPCMs) have made tremendous advancements in recent years, owing to their increased demand for a variety of energy storage applications. In this paper, current microencapsulation techniques, enhancement, and... Read More about The microencapsulation, thermal enhancement, and applications of medium and high-melting temperature phase change materials: A review.

Prospects of Bioenergy Production for Sustainable Rural Development in Ghana (2021)
Journal Article
Nelson, N., Darkwa, J., & Calautit, J. (2021). Prospects of Bioenergy Production for Sustainable Rural Development in Ghana. Journal of Sustainable Bioenergy Systems, 11(04), 227-259. https://doi.org/10.4236/jsbs.2021.114015

Biomass supplies about 80% of the energy needs for cooking and heating in rural Ghana. It is predominantly used in traditional and inefficient forms (firewood and charcoal), which presents environmental and health concerns. In order to better the liv... Read More about Prospects of Bioenergy Production for Sustainable Rural Development in Ghana.

Real-time monitoring of occupancy activities and window opening within buildings using an integrated deep learning-based approach for reducing energy demand (2021)
Journal Article
Tien, P. W., Wei, S., Calautit, J. K., Darkwa, J., & Wood, C. (2022). Real-time monitoring of occupancy activities and window opening within buildings using an integrated deep learning-based approach for reducing energy demand. Applied Energy, 308, Article 118336. https://doi.org/10.1016/j.apenergy.2021.118336

Occupancy behaviour in buildings can impact the energy performance and operation of heating, ventilation and air-conditioning (HVAC) systems. HVAC, which uses conventional control strategies or “fixed” setpoint schedules, could not adjust to the cond... Read More about Real-time monitoring of occupancy activities and window opening within buildings using an integrated deep learning-based approach for reducing energy demand.

Performance evaluation of combined solar chimney and radiative cooling ventilation (2021)
Journal Article
Suhendri, S., Hu, M., Su, Y., Darkwa, J., & Riffat, S. (2022). Performance evaluation of combined solar chimney and radiative cooling ventilation. Building and Environment, 209, Article 108686. https://doi.org/10.1016/j.buildenv.2021.108686

Passive cooling is inevitable for buildings to be resilient to global warming. While many forms of passive cooling techniques have been developed, passive radiative cooling (RC), as an emerging technology, is still not widely applied in buildings. Du... Read More about Performance evaluation of combined solar chimney and radiative cooling ventilation.

The impact of thermal insulation on cooling energy consumption and optimal insulation thickness for underground tunnel (2021)
Journal Article
Wang, Y., Wang, C., Gao, S., Zheng, X., & Darkwa, J. (2021). The impact of thermal insulation on cooling energy consumption and optimal insulation thickness for underground tunnel. Sustainable Energy Technologies and Assessments, 47, Article 101495. https://doi.org/10.1016/j.seta.2021.101495

The provision of mechanical cooling in deep mines comes with a significant energy cost as a significant amount of heat transfers from surrounding rock to the airflow. Thermal insulation can be applied to reduce such heat transfer, thereby cutting dow... Read More about The impact of thermal insulation on cooling energy consumption and optimal insulation thickness for underground tunnel.

A deep learning approach towards the detection and recognition of opening of windows for effective management of building ventilation heat losses and reducing space heating demand (2021)
Journal Article
Tien, P. W., Wei, S., Liu, T., Calautit, J., Darkwa, J., & Wood, C. (2021). A deep learning approach towards the detection and recognition of opening of windows for effective management of building ventilation heat losses and reducing space heating demand. Renewable Energy, 177, 603-625. https://doi.org/10.1016/j.renene.2021.05.155

Building ventilation accounts for up to 30% of the heat loss in commercial buildings and 25% in industrial buildings. To effectively aid the reduction of energy consumption in the building sector, the development of demand-driven control systems for... Read More about A deep learning approach towards the detection and recognition of opening of windows for effective management of building ventilation heat losses and reducing space heating demand.

Experimental investigation on performance improvement of thermoelectric generator based on phase change materials and heat transfer enhancement (2021)
Journal Article
Wang, Y., Peng, Y., Guo, K., Zheng, X., Darkwa, J., & Zhong, H. (2021). Experimental investigation on performance improvement of thermoelectric generator based on phase change materials and heat transfer enhancement. Energy, 229, Article 120676. https://doi.org/10.1016/j.energy.2021.120676

Thermoelectric application has been widely researched due to its various advantages. Its use has been limited to niche industrial applications and exploratory research development due to the poor economic viability. It is essential to achieve the opt... Read More about Experimental investigation on performance improvement of thermoelectric generator based on phase change materials and heat transfer enhancement.

Experimental Data on Water Vapour Adsorption on Silica Gel in Fully Packed and Z-Annulus Packed Beds (2021)
Journal Article
Yeboah, S. K., & Darkwa, J. (2021). Experimental Data on Water Vapour Adsorption on Silica Gel in Fully Packed and Z-Annulus Packed Beds. Data in Brief, 34, Article 106736. https://doi.org/10.1016/j.dib.2021.106736

Experimental data on water vapour adsorption on silica gel in four packed bed configurations namely fully packed bed (FPB), large annulus packed bed (LAPB), medium annulus packed bed (MAPB) and small annulus packed bed (SAPB) are presented. Raw tempe... Read More about Experimental Data on Water Vapour Adsorption on Silica Gel in Fully Packed and Z-Annulus Packed Beds.

Potential of Bioenergy in Rural Ghana (2021)
Journal Article
Nelson, N., Darkwa, J., Calautit, J., Worall, M., Mokaya, R., Adjei, E., Kemausuor, F., & Ahiekpor, J. (2021). Potential of Bioenergy in Rural Ghana. Sustainability, 13(1), Article 381. https://doi.org/10.3390/su13010381

Crop residues are common in rural Ghana due to the predominant role agriculture plays in livelihood activities in these communities. In this paper we investigate the prospects of exploiting agricultural crop residues for rural development in Ghana th... Read More about Potential of Bioenergy in Rural Ghana.

Development of TiO2/RT–35HC based nanocomposite phase change materials (NCPCMs) for thermal management applications (2020)
Journal Article
Arshad, A., Jabbal, M., Shi, L., Darkwa, J., Weston, N. J., & Yan, Y. (2021). Development of TiO2/RT–35HC based nanocomposite phase change materials (NCPCMs) for thermal management applications. Sustainable Energy Technologies and Assessments, 43, Article 100865. https://doi.org/10.1016/j.seta.2020.100865

This experimental study covers the development of novel nanocomposite phase change materials (NCPCMs) based on RT–35HC as a phase change material (PCM) and titanium oxide (TiO2) as thermal conductivity enhancement material, for thermal management app... Read More about Development of TiO2/RT–35HC based nanocomposite phase change materials (NCPCMs) for thermal management applications.

Experimental investigation into the integration of solid desiccant packed beds with oscillating heat pipes for energy efficient isothermal adsorption processes (2020)
Journal Article
Yeboah, S. K., & Darkwa, J. (2021). Experimental investigation into the integration of solid desiccant packed beds with oscillating heat pipes for energy efficient isothermal adsorption processes. Thermal Science and Engineering Progress, 21, Article 100791. https://doi.org/10.1016/j.tsep.2020.100791

The heat of adsorption released during physical adsorption of water vapour on solid desiccants increases its surface vapour pressure consequently decreasing its adsorption capacity. In packed beds, this raises the bed temperature subsequently increas... Read More about Experimental investigation into the integration of solid desiccant packed beds with oscillating heat pipes for energy efficient isothermal adsorption processes.

Implementation of Passive Radiative Cooling Technology in Buildings: A Review (2020)
Journal Article
Suhendri, S., Hu, M., Su, Y., Darkwa, J., & Riffat, S. (2020). Implementation of Passive Radiative Cooling Technology in Buildings: A Review. Buildings, 10(12), 1-28. https://doi.org/10.3390/buildings10120215

Radiative cooling (RC) is attracting more interest from building engineers and architects. Using the sky as the heat sink, a radiative cooling material can be passively cooled by emitting heat to the sky. As a result of the development of material te... Read More about Implementation of Passive Radiative Cooling Technology in Buildings: A Review.

Experimental data on Helically Coiled Oscillating Heat Pipe (HCOHP) design and thermal performance (2020)
Journal Article
Yeboah, S. K., & Darkwa, J. (2020). Experimental data on Helically Coiled Oscillating Heat Pipe (HCOHP) design and thermal performance. Data in Brief, 33, Article 106505. https://doi.org/10.1016/j.dib.2020.106505

Experimental and derived data from three Helically Coiled Oscillating Heat Pipes (HCOHPs) charged with ethanol, methanol and deionized water working fluids respectively are presented. The data was obtained from prototypes of the HCOHPs fabricated out... Read More about Experimental data on Helically Coiled Oscillating Heat Pipe (HCOHP) design and thermal performance.

Performance comparison of two solar cooking storage pots combined with wonderbag slow cookers for off-sunshine cooking (2020)
Journal Article
Mawire, A., Lentswe, K., Owusu, P., Shobo, A., Darkwa, J., Calautit, J., & Worall, M. (2020). Performance comparison of two solar cooking storage pots combined with wonderbag slow cookers for off-sunshine cooking. Solar Energy, 208, 1166-1180. https://doi.org/10.1016/j.solener.2020.08.053

Two similar storage cooking pots are experimentally evaluated and compared during solar cooking and storage off-sunshine cooking periods. One storage pot has sunflower oil as the sensible heat storage material, while the other has erythritol as the p... Read More about Performance comparison of two solar cooking storage pots combined with wonderbag slow cookers for off-sunshine cooking.

Experimental study of thermal fracturing of Hot Dry Rock irradiated by moving laser beam: Temperature, efficiency and porosity (2020)
Journal Article
Wang, Y., Jiang, J., Darkwa, J., Xu, Z., Zheng, X., & Zhou, G. (2020). Experimental study of thermal fracturing of Hot Dry Rock irradiated by moving laser beam: Temperature, efficiency and porosity. Renewable Energy, 160, 803-816. https://doi.org/10.1016/j.renene.2020.06.138

A new laser irradiation fracturing method is employed to crack the Hot Dry Rock (HDR) and variations of rock temperature, specific energy (SE) and modified specific energy (MSE), thermal damages and open porosity of granite samples caused by moving l... Read More about Experimental study of thermal fracturing of Hot Dry Rock irradiated by moving laser beam: Temperature, efficiency and porosity.

Thermo-mechanical and moisture absorption properties of fly ash-based lightweight geopolymer concrete reinforced by polypropylene fibers (2020)
Journal Article
Wang, Y., Zheng, T., Zheng, X., Liu, Y., Darkwa, J., & Zhou, G. (2020). Thermo-mechanical and moisture absorption properties of fly ash-based lightweight geopolymer concrete reinforced by polypropylene fibers. Construction and Building Materials, 251, Article 118960. https://doi.org/10.1016/j.conbuildmat.2020.118960

An experimental investigation on the thermo-mechanical and moisture absorption properties of lightweight geopolymer concrete prepared with fly ash, NaOH, sodium silicate and Polypropylene Fibers (PF) is presented in this study. The effects of dry den... Read More about Thermo-mechanical and moisture absorption properties of fly ash-based lightweight geopolymer concrete reinforced by polypropylene fibers.