Article
Multidisciplinary Sciences
Noor Fouad, A. Hamza, Sattar Aljabair
Summary: The thermal performance parameters of an improved heat exchanger tube with various vortex generator inserts were investigated using numerical and experimental methods. The tube equipped with a double V-cut twisted tape and hybrid nanofluid displayed increased thermal performance compared to a plain twisted tape. The greater vortex flow induced by the V-cuts resulted in more active thermal boundary layer disturbance and a higher heat transfer rate.
Article
Thermodynamics
Sumit Kr. Singh, Jahar Sarkar
Summary: Experimental studies show that the use of hybrid nanofluid and different shapes of twisted tape inserts can improve heat transfer and pressure drop characteristics, with Nusselt number and friction factor increasing with decreasing twisting ratio, increasing depth ratio, decreasing width ratio, and decreasing nanofluid inlet temperature.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Thermodynamics
Keyvan Ahmadi, Saber Khanmohammadi, Shoaib Khanmohammadi, Mehdi Bahiraei, Quang-Vu Bach
Summary: In this study, a numerical simulation is conducted to improve the thermal performance of a circular pipe using elliptical-cut twisted tape inserts and nanofluid. The results show that the use of elliptical-cut twisted tape and nanofluid can significantly enhance heat transfer and thermal efficiency factor.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Chemistry, Multidisciplinary
Yongfeng Ju, Tiezhu Zhu, Ramin Mashayekhi, Hayder Mohammed, Afrasyab Khan, Pouyan Talebizadehsardari, Wahiba Yaici
Summary: Increasing the number of semi-twisted tapes in a heat exchanger pipe leads to enhancement in heat transfer and friction factor, which is significant for heat exchange using nanofluids.
Article
Chemistry, Multidisciplinary
Omer A. A. Alawi, Haslinda Mohamed Kamar, Mayadah W. W. Falah, Omar A. A. Hussein, Ali H. H. Abdelrazek, Waqar Ahmed, Mahmoud Eltaweel, Raad Z. Z. Homod, Nadhir Al-Ansari, Zaher Mundher Yaseen
Summary: Mono, hybrid, and ternary nanofluids were tested in plain and twisted-tape pipes using k-omega shear stress transport turbulence models. The thermal performance and pressure drop of different nanofluids were compared at varying Reynolds numbers. Results showed that the twisted pipe had a higher outlet temperature and better energy utilization than the plain pipe. SiO2/DW exhibited improved heat transfer performance and reduced pressure drop at Re = 9,000. Overall, nanofluids showed superior thermohydraulic performance compared to distilled water, with DW having a higher thermohydraulic efficiency at Re = 15,000.
NANOTECHNOLOGY REVIEWS
(2023)
Article
Multidisciplinary Sciences
Md Tauhidur Rahman, Khairul Habib, Md Niamul Quader, Navid Aslfattahi, Kumaran Kadirgama, Likhan Das
Summary: This study investigates the impact of porosity density of twisted tape inserts on temperature distribution, fluid velocities, heat transfer coefficients, Nusselt numbers, turbulent kinetic energy, and performance. The results demonstrate that high porosity TTI significantly reduces temperature spans, increases fluid velocities, enhances heat transfer efficiency, and exhibits superior performance compared to low porosity and typical TTI, particularly at Re = 12500.
Article
Thermodynamics
Xiang Cheng, Song Feng, Qincheng Bi
Summary: This experiment investigated the influence of surface coke deposition on the flow and heat transfer of hydrocarbon fuel in circular tubes with twisted-tape inserts under supercritical pressures. The results showed that the use of twisted-tape inserts improved heat transfer, reduced coke deposition, and proposed a well-predicted correlation of the Nusselt number.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Mechanical
Ece Ayli, Eyup Kocak
Summary: This numerical study investigates the impact of twisted tape inserts on heat transfer. The results show that the tube with twisted tape and different numbers of tape performs better in terms of thermo-hydraulic performance. An artificial neural network model is then used to predict the Nusselt number for heated tubes with twisted inserts. The optimized model provides high precision with R2 = 0.97043. The developed ANN architecture can also predict the heat transfer enhancement performance of similar problems with R2 values higher than 0.93.
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
Hong-Jin Joo, Hee-Youl Kwak, Minsuk Kong
Summary: The present study experimentally investigates the effect of twisted tape inserts on the thermal performance of an eccentric inlet and outlet heat pipe evacuated-tube solar thermal collector (HP-ESTC). The results show that the addition of twisted tape inserts enhances heat transfer performance by eliminating stagnation flow, reducing flow skewness, and generating rotating flow. A comprehensive performance analysis considering both heat transfer and pressure drop characteristics confirms that using twisted tape inserts can improve overall performance by approximately 7.7%. To assess its applicability for commercial HP-ESTCs, an HP-ESTC containing twisted tape inserts was manufactured and tested outdoors.
Article
Green & Sustainable Science & Technology
Abolfazl Fattahi
Summary: Increasing demand for energy worldwide has highlighted the importance of renewable energies, with solar energy playing a crucial role. Research has shown that in solar heat transfer, increasing the volume friction of hybrid nanofluids and the wall roughness of collector tubes can significantly enhance performance.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2021)
Article
Thermodynamics
Ramin Mashayekhi, Hossein Arasteh, Pouyan Talebizadehsardari, Apurv Kumar, Morteza Hangi, Alireza Rahbari
Summary: By simulating the effects of different design parameters, it is found that inserting twisted tape inside a plain tube can significantly enhance heat transfer performance, with rotating twisted tape showing more prominent improvement. With the increase in Reynolds number, the enhancement in average Nusselt number increases in stationary configurations and decreases in rotating configurations.
HEAT TRANSFER ENGINEERING
(2022)
Article
Energy & Fuels
Rishabh Agarwal, Rajesh Maithani, Sachin Sharma, Anil Kumar, Ajay Kumar
Summary: This study optimized the parameters of twisted tape insert in a heat exchanger tube with SiO2/H2O based nanofluid flow. The goal was to maximize heat transfer while minimizing pressure drop. The optimized parameter values for a specific range of Reynolds number were found to be W-T/D-T of 0.8, L-T/W-T of 1.74, phi of 1.25 vol.%, and Re of 17,000.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Energy & Fuels
Bhavik Patel, R. M. Sarviya, S. P. S. Rajput
Summary: This paper presents a numerical study on heat transfer enhancement in a tubular heat exchanger using novel anti-clockwise clockwise twisted (ACCT) tapes. The results show that the ACCT tapes generate multiple vortices in the flow, increasing turbulent kinetic energy and improving heat transfer performance. By selecting appropriate twist angles and ratios, a beneficial balance between heat transmission rate and friction factor can be achieved.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2022)
Article
Thermodynamics
Javad Mozaffari, Seyed Ali Agha Mirjalily, Amir Javad Ahrar
Summary: This study experimentally examines the heat transfer rate of Al2O3-water nanofluid-flow in a tube with twisted tape inserts, demonstrating the combined effect of nanoparticles and twisted tape inserts on enhancing heat transfer coefficient while influencing pressure drop. The research also explores the influence of nanoparticles' volume fractions in the turbulent regime of a tube with constant temperature boundary condition.
Article
Thermodynamics
Santinath Bairagi, Ranendra Roy, Bijan Kumar Mandal
Summary: This study conducts a numerical investigation on the heat transfer properties of water-based Al2O3 nanofluids flowing through circular tubes, both with and without twisted tape inserts. The results show that twisted tape significantly enhances the heat transfer rate, while the nanofluid alone only provides a modest improvement. The friction factor increases with the nanoparticle volume fraction, but the effect on heat transfer rate is more pronounced. The best thermohydraulic performance is achieved with a 5% volume fraction of nanoparticles and twisted tape inserts.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2023)
Article
Chemistry, Physical
Ahmad Rujhan Mohd Rais, Zon Fazlila Mohd Ahir, Nurul Aqidah Mohd Sinin, Nur Fairuz Mohd Rostan, Suhaila Sepeai, Mohd Adib Ibrahim, Kamaruzzaman Sopian
Summary: This paper explores the potential of using phosphoric acid as the emitter formation for silicon solar cells, which is less harmful to the environment and human health compared to the conventional toxic process. Different depths of junction were achieved through dip coating experiments at various temperatures and times. The experimental results of phosphorus activation using 20% H3PO4 supported the calculated junction depth. The overall efficiency of the n-type emitter on n-Si solar cell was determined using the measured sheet resistance and was found to be 8.6%.
Review
Energy & Fuels
A. A. Lahimer, A. A. Razak, A. F. Sharol, K. Sopian
Summary: This review focuses on the impact of interior cabin soak temperature on commercial vehicles parked under direct sunlight and evaluates various methods to reduce temperature. It has been found that high cabin temperature poses risks to occupants and the most feasible passive technologies include phase-change materials, solar chimneys, aluminium covers, solar-powered ventilation, and reflective glass. The choice of technology depends on factors such as energy source type, economic feasibility, end-user behavior, and government regulations.
Correction
Energy & Fuels
Haris M. Khalid, Zimran Rafique, S. M. Muyeen, Abdul Raqeeb, Zafar Said, R. Saidur, Kamaruzzaman Sopian
Article
Multidisciplinary Sciences
A. S. Najm, Azza Al-Ghamdi, Majdi T. Amin, Ahmed Al Ghamdi, Hazim Moria, Araa Mebdir Holi, Azher M. Abed, Asla Abdullah AL-Zahrani, K. Sopian, Badariah Bais, Abbas J. Sultan
Summary: This study focuses on improving the overall efficiency of CZTS thin film solar cells by exploring a novel, low-cost, and simplified deposition method to enhance the optoelectronic properties of the buffer layer. The Linker Assisted and Chemical Bath Deposition (LA-CBD) method is introduced as an innovative and effective approach to adjust the absorbers' structure and sensitized CdS thin film. The results demonstrate improved bandgap, reduced strain level, larger grain size, and enhanced crystalline property, indicating the potential use of CdS films as a buffer layer for CZTS photovoltaic devices.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Physical
Zon Fazlila Mohd Ahir, Suhaila Sepeai, Nurul Aqidah Mohd Sinin, Ahmad Rujhan Mohd Rais, Kamaruzzaman Sopian, Mohd Adib Ibrahim
Summary: This study focuses on the fabrication of Si solar cells using less toxic materials and an environmentally friendly process. It demonstrates that the use of a less toxic phosphoric acid (H3PO4) solution for emitter formation and SiO2 for passivation can produce comparable results to industry standards.
Article
Green & Sustainable Science & Technology
Miqdam T. Chaichan, Hussein A. Kazem, Moafaq K. S. Al-Ghezi, Ali H. A. Al-Waeli, Ali J. Ali, Kamaruzzaman Sopian, Abdul Amir H. Kadhum, Wan Nor Roslam Wan Isahak, Mohd S. Takriff, Ahmed A. Al-Amiery
Summary: The study aimed to find the most suitable nanofluid for cooling photovoltaic/thermal (PVT) systems in the harsh summer conditions of Baghdad. Multi-walled carbon nanotubes (MWCNTs) were selected as additive particles, and various parameters were tested. Water was chosen as the base fluid, and when 1% MWCNT mass fraction was added, the thermal conductivity (TC) of all tested fluids increased significantly. A nanofluid consisting of 0.5% MWCNTs, water, and CTAB as the surfactant was found to be the most effective. This nanofluid-cooled PVT system achieved higher electrical and thermal efficiencies compared to standalone PV and water-cooled PVT systems, confirming its suitability for the severe weather conditions of Baghdad.
Article
Thermodynamics
Nurul Syakirah Nazri, Ahmad Fudholi, Evgeny Solomin, Maulana Arifin, Mohammad Hossein Yazdi, Tri Suyono, Eka Rakhman Priandana, Muslizainun Mustapha, Muhamad Hafiz Hamsan, Afifuddin Husairi Hussain, Mohd Fadhli Shah Khaidzir, Muhammad Ibrahim Ali Zaini, Nurul Nazli Rosli, Masita Mohammad, Kamaruzzaman Sopian
Summary: A new hybrid system, PVT-TE, has been proposed to enhance the conversion efficiency of PV cells. Experimental results show that the PVT-TE system outperforms the conventional PVT system in both thermal and electrical performance. This study provides the basis for further optimization of hybrid systems.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Anwer B. Al-Aasam, Adnan Ibrahim, Kamaruzzaman Sopian, M. Bassam Abdulsahib, Mojtaba Dayer
Summary: The thermal performance of a photovoltaic thermal (PVT) collector with a twisted absorber tube and nanoparticle-enhanced phase change material (Nano-PCM) was evaluated. The photovoltaic, thermal, and combined photovoltaic thermal efficiencies were assessed using an indoor solar simulator. Circular and twisted absorber tubes with Nano-PCM were tested in two designs. Water with different volume fractions of SiC nanofluids was used as the working fluid. The highest efficiencies were achieved by the PVT-PCM with twisted tube and 0.6% nanofluids, with photovoltaic, thermal, and combined photovoltaic thermal efficiencies of 9.57, 84.74, and 94.31, respectively.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Muhammad Amir Aziat Bin Ishak, Adnan Ibrahim, Ahmad Fazlizan, Mohd Faizal Fauzan, Kamaruzzaman Sopian, Aqil Afham Rahmat
Summary: A reversed circular flow jet impingement (RCFJI) was used as a cooling mechanism for a bifacial photovoltaic thermal (PVT) solar collector, and the exergy efficiency of this system was analyzed. The experimental results showed that under a solar irradiance of 900W/m2 and a mass flow rate of 0.14kg/s, the highest photovoltaic exergy and thermal exergy achieved were 47.2W and 9.67W, respectively. The exergy efficiency reached a maximum value of 12.64% under the solar irradiance of 900W/m2, with the optimal operational mass flow rate determined as 0.06kg/s.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Review
Thermodynamics
Hussein A. Kazem, Ali H. A. Al-Waeli, Miqdam T. Chaichan, K. Sopian, Ahmed Said Al Busaidi, Aslan Gholami
Summary: This paper reviews the literature on the use of photovoltaic thermal air collectors (PV-T) and integrated greenhouse drying systems for PV-T air collectors as a means to reduce fossil fuel consumption and mitigate global warming. Solar drying is an effective method to preserve crops for long-term use, especially in countries with limited electricity sources. The review highlights the superiority of PV-T air collectors over individual PV modules in terms of energy storage and drying parameter control. It provides valuable insights and data for the development and enhancement of thermal models for combined solar systems.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Muhammad Amir Aziat Bin Ishak, Adnan Ibrahim, Kamaruzzaman Sopian, Mohd Faizal Fauzan, Muhammad Aqil Afham Rahmat, Ag Sufiyan Abd Hamid
Summary: The impingement mechanism in solar collectors has been extensively studied for its ability to improve efficiency. This article provides a comprehensive review of recent studies on jet impingement solar collectors, discussing their design and performance in various applications. The review is classified into four main components: single pass, double pass, concentrated, and jet configuration. The impact of factors such as nozzle pitch and diameter on heat transfer properties is also discussed. Further research is needed for single pass-single ducts using jet impingement, and double pass-solar collectors are found to outperform single pass-solar collectors thermally due to higher heat extraction rates and doubled transfer surfaces.
INTERNATIONAL JOURNAL OF RENEWABLE ENERGY RESEARCH
(2023)
Article
Energy & Fuels
Muhammad Amir Aziat Bin Ishak, Adnan Ibrahim, Kamaruzzaman Sopian, Mohd Faizal Fauzan, Muhammad Aqil Afham Rahmat, Ag Sufiyan Abd Hamid
Summary: This paper presents a Novel Circular Flow Jet Impingement applied to a bifacial photovoltaic thermal (PVT) solar collector to enhance its energy performance. CFD COMSOL simulation was used to analyze the energy performance of the PVT solar collector. The study found that the optimum design for the Circular Flow Jet Impingement was achieved using a 40mm diameter and 20mm depth, with a maximum photovoltaic, thermal, and overall efficiency of 63%, 11.09%, and 74.09% at an irradiance of 900W/m2 and flow rate of 0.14kg/s.
INTERNATIONAL JOURNAL OF RENEWABLE ENERGY RESEARCH
(2023)
Article
Energy & Fuels
Mojtaba Dayer, Ag Sufiyan Abd Hamid, Kamaruzzaman Sopian, Adnan Ibrahim, Anwer. B. Al-Aasam, Bassam Abdulsahib, Saeed Rahmanian
Summary: This study introduces a novel design of Photovoltaic thermal collector (PVT) by integrating Phase Change Materials (PCM) with Copper Foam Matrix (CFM) for passive cooling and serpentine copper tubes for active cooling. The simulation results showed that incorporating PCM and CFM can decrease the PV surface temperature and increase electrical efficiency.
INTERNATIONAL JOURNAL OF RENEWABLE ENERGY RESEARCH
(2023)
Article
Energy & Fuels
Jalal Assadeg, Kamaruzzaman Sopian, Adnan Ibrahim, Ahmad Fudholi, Noshin Fatima, Ali H. A. Al-Waeli, Ag Sufiyan Abd Hamid
Summary: This research paper presents a mathematical model of a solar air collector with a finned absorber and nano-enhanced PCM. The model simulates the thermal and thermo-hydraulic performance of the collector considering various operating parameters. The optimal energy and exergy efficiencies were achieved at a solar irradiance of 1000 W/m2 and a mass flow rate of 0.06 kg/s. The collector showed significant improvement potentials in terms of power output at different irradiance levels.
INTERNATIONAL JOURNAL OF RENEWABLE ENERGY RESEARCH
(2023)
Review
Environmental Sciences
Ali H. A. Al-Waeli, Kamaruzzaman Sopian, Hussein A. Kazem, Miqdam T. Chaichan
Summary: The bi-fluid photovoltaic thermal (PVT) collector is a technology that provides more heating options and improved cooling capabilities for PV modules. This review paper critically discusses the concept, applications, and research achievements of this technology, with a focus on climatic and operational parameters. The different operational modes, including water in both channels, water in one channel and air in the other, and air in both channels, are discussed in detail, along with their impact on the performance of the utilized photovoltaic modules. The effect of mass flow rate on the energy and exergy efficiency of the collector is also investigated by varying one working fluid while keeping the other constant.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
