- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- EDITOR-IN-CHIEF: Prof. Dr. Isam Janajreh. Khalifa University UAE
- Medium: Online
- ISSN: 1923-7316
- Country: Canada
The International Journal of Thermal and Environmental Engineering (IJTEE) is a high-quality scientific journal devoted to fields of Thermal and Environmental Engineering It aims to provide a highly readable and valuable addition to the literature which will serve as an indispensable reference tool for years to come. The coverage of the journal includes all new theoretical and experimental findings in the fields of Thermal and Environmental Engineering or closely related fields. The journal also encourages the submission of critical review articles covering advances in recent research of such fields as well as technical notes.
INTRODUCTION
The Editor-in-Chief and the Editorial Board are very committed to build the Journal as one of the leading international journals in Thermal and Environmental Engineering in the next few years. With the support of the International Association for Sharing Knowledge and Sustainability (IASKS), it is expected that a heavy resource to be channeled into the Journal to establish its international reputation. The Journal’s reputation will be enhanced from arrangements with several organizers of international conferences in publishing selected best papers of the conference proceedings. The journal is planning to publish 4 issues per year.
AIMS AND SCOPE
The International Journal of Thermal and Environmental Engineering (IJTEE) is a refereed international journal to be of interest and use to all those concerned with research in various fields of, or closely related to Thermal and Environmental Engineering disciplines. The International Journal of Thermal and Environmental Engineering (IJTEE) aims to provide a highly readable and valuable addition to the literature which will serve as an indispensable reference tool for years to come. The coverage of the journal includes all new theoretical and experimental findings in the fields of Thermal and Environmental Engineering or closely related fields. The journal also encourages the submission of critical review articles covering advances in recent research of such fields as well as technical notes.
Latest Articles of IJTEE
Assessment of ultrasound assisted coalescence of water-in-crude oil emulsion: Influence of piezoelectric transducer material under batch and continuous conditions
IJTEE, Volume-19 , Issue 1 (2022), PP 47 - 54
Published: 26 Oct 2022
DOI: 10.5383/ijtee.19.01.006
by Idowu Adeyemi, Mahmoud Meribout, Lyes Khezzar, Nabil Kharoua, Khalid AlHammadi from Department of Mechanical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates, Department of Electrical Engineering and Computer Science, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates, and Department of Mechanical Engineering, Ecole Nationale Polytechnique de Constantine, Constantine, Algeria
Abstract: In this work, the potentiality of lead free ultrasound (US) materials towards crude oil emulsion demulsification was assessed. The assessment is crucial because of the detrimental environmental and health impacts of lead zirconate titanate, which is widely used for US coalescence presently. The production or utilization of lead zirconate titanate (PZT) results in the release of vaporized hazardous lead oxide (PbO) at elevated temperature or dissolution of poisonous lead into aqueous medium. Hence, the analysis of the effect of different piezoelectric material type (PZT, polyvinylidene fluoride (PVDF) and lithium niobate (LiNbO3)) on domain acoustic pressure distribution and the subsequent coalescence of binary droplets under batch conditions was conducted. The lead-free piezoelectric materials (PVDF and LiNbO3) were assessed with the PZT in order to determine their viability for droplet coalescence. The piezoelectric materials were subjected to mechanical oscillation under resonance in order to allow for optimum performance. Moreover, the US coalescence was examined under continuous flow conditions to determine coalescence behavior and performance during online emulsion treatment. The eigen-frequency analysis provided the resonance frequencies of 19.61, 26.04 and 57.80 kHz for PVDF, PZT and Lithium niobate, respectively. Moreover, the acoustic pressure in the emulsion domain varied in magnitude and distribution. The order of the coalescence time for the binary droplets followed the order PZT<PVDF<LiNbO3. Furthermore, increasing the flow velocities resulted in slight reduction in the coalescence time and energy consumed for the different piezoelectric materials evaluated. read more... read less...
Keywords: Piezoelectric transducer, Ultrasound, Coalescence, Demulsification, Lead free, Crude Oil Emulsion
Thermoacoustic Refrigeration: Short Review
IJTEE, Volume-19 , Issue 1 (2022), PP 29 - 45
Published: 26 Oct 2022
DOI: 10.5383/ijtee.19.01.005
by Omar Ahmed Al-Mufti and Isam Janajreh from Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi, UAE
Abstract: Thermoacoustic is the science that studies the conversion of the heat into acoustical sound and vice versa. The conversion of heat to acoustic power is done through Thermoacoustic engine (TAE). This generated acoustic power can be converted to another and useful form such as mechanical or electrical energy. On the other hand, Thermoacoustic refrigerator (TAR) or heat pump is a device that uses acoustic sound to pump heat from a lower temperature reservoir. The most distinct feature of thermoacoustic systems is that they do not have moving parts, which makes them reliable. Thermoacoustic engine can recycle any source of waste heat and use sustainable heat like concentrated solar. Also, in contrast to conventional refrigeration methods, thermoacoustic refrigerator spares the usage of environmentally harmful gases that is daunting the centralized cooling industry. There is no doubt the thermoacoustic technology has been considered in various applications with some unspoken advancement. In this manuscript we intend to review the fundamentals of thermoacoustics and highlight their recent developments. Additionally, analytical simulation of thermoacoustic refrigerator will be discussed and validated against experimental published work. The goal is to reveal the effect of different parameters on the performance in an attempt to establish design guidelines for an improved technology metrics. The future prospects of thermoacoustic refrigeration are also presented at the end of this study. read more... read less...
Keywords: Thermoacoustic engine; Thermoacoustic refrigerator; Thermal and viscous penetration depth; Standing and traveling wave
Thermal Investigation of Nanofluids in Heat Exchanger Tubes using Two-Phase Approach
IJTEE, Volume-19 , Issue 1 (2022), PP 23 - 28
Published: 19 Sep 2022
DOI: 10.5383/ijtee.19.01.004
by M Mubashir Farid, Samia Sadaf, M Shahid Farooq, Ussama Ali from Department of Mechanical Engineering, University of Engineering and Technology Lahore, Pakistan
Abstract: This paper investigates the effect of nanofluids in a flat-tube heat exchanger on the heat transfer under the influence of constant heat flux using computational fluid dynamics (CFD) analysis. Two nanofluids: Titanium Oxide (TiO2)/water and Aluminum Oxide (Al2O3)/water were used with nanoparticles of diameter 10 nm. A two-phase approach with a mixture model is adopted in the CFD analysis. The heat transfer coefficient was evaluated at Reynolds number of 1750 utilizing various volume concentrations of nanoparticles (1%, 3%, 5%, and 7%). It was observed that an increase in the concentration of the nanoparticles resulted in an increase in the value of heat transfer coefficient. The results observed at 7% volume concentration, using two-phase approach, showed 5% and 8% enhancement in the heat transfer coefficient for TiO2/water and Al2O3/water, respectively, when compared with the results of single-phase technique. read more... read less...
Keywords: Flat tube, Heat transfer coefficient, Two-phase approach, Nanofluids
Parametric Sensitivity of Water Collection on Desiccant Coated Heat Exchanger
IJTEE, Volume-19 , Issue 1 (2022), PP 15 - 22
Published: 19 Sep 2022
DOI: 10.5383/ijtee.19.01.003
by Muna AlQaydi, Md Islam, Isam Janajreh from Khalifa University of Science and Technology, Abu Dhabi, UAE
Abstract: Atmospheric water harvesting (AWH) is used to address the current scarcity of fresh water. Sorption-based AWH technology using desiccant coated heat exchanger (DCHE) could enable a good water supply in arid regions since sorbents can grab moisture from arid environment and then release water once it is thermally generated. Recent developments focus on novel adsorbents with high sorption capacity at low humidity and low regeneration temperature. However, a thermodynamic analysis on overall system to predict the best operating parameters and how it affects system efficiency has not been studied. In this study, we investigated the energy and heat transfer properties of desiccant-coated heat exchanger. A one-dimensional mathematical model is developed to predict the performance of a DCHE system which uses super-porous hydrogel (SPH) made of N-isopropylacrylamide (NIPAM) as a desiccant material. The effects of inlet temperature, inlet humidity ratio, air mass flow rate, and cold side temperature brought by using thermo-electric cooling (TEC) on the amount of water collected, COP, and second law efficiency of the system were analyzed. The results suggest that the rate of water production and COP of the system increased as the temperature and humidity of the air increased. It emerged that increasing airflow increases water intake and COP due to the improved heat transfer through the system. However, rising cold side temperature of TEC decreases water production rate and COP while it improves second law efficiency because of reduced heat transfer and entropy generation. The obtained results show that water harvesting using the proposed system with thermoelectric cooling device and solar energy is feasible. read more... read less...
Keywords: Cooling Load, Air-Conditioning, Desiccant coated heat exchanger, Atmospheric water collection
Numerical Simulation of Laminar Flow Over a Transversely Oscillating Circular Cylinder
IJTEE, Volume-19 , Issue 1 (2022), PP 07 - 13
Published: 19 Sep 2022
DOI: 10.5383/ijtee.19.01.002
by Ussama Ali, Ayoola Brimmo, Md Islam, Isam Janajreh from Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi, UAE and Department of Mechanical Engineering, University of Engineering and Technology, Lahore, 54890, Pakistan
Abstract: Two-dimensional low Reynolds number flow (Re = 100) over a transversely oscillating circular cylinder placed in a uniform stream is numerically investigated in this work using the commercial software Ansys/Fluent. The forced transverse oscillations of the cylinder are carried out to mimic the specific cases of flow-induced vibrations. The frequency ratio is varied between 0 – 2, where 0 corresponds to stationary cylinder. The layering technique of dynamic mesh is employed to incorporate the cylinder motion. The unsteady flow simulations are performed to solve for URANS. The parameters studied are the coefficients of lift and drag, vortex shedding frequency, and the vortex shedding patterns. The results reveal that the cylinder oscillation induces modulation in the lift and drag coefficients in terms of their frequency and amplitude. The lock-in occurs at frequency ratio of 1 where the frequency of cylinder oscillation matches with the natural vortex shedding frequency of the cylinder. Maximum average drag coefficient is observed at the lock-in condition however the lift coefficient is found to increase with the frequency ratio. The 2S vortex shedding pattern is observed in the vorticity contours for all the cases studied. read more... read less...
Keywords: Forced transverse oscillations, Unsteady flow, Lift and drag coefficients, Vortex shedding pattern
Effect of Building Orientation on The Cooling Load: The UAE Case Study
IJTEE, Volume-19 , Issue 1 (2022), PP 01 - 05
Published: 19 Sep 2022
DOI: 10.5383/ijtee.19.01.001
by Ahmad Hasan, Md Islam, Isam Janajreh from Khalifa University of Science and Technology, Abu Dhabi, UAE
Abstract: UAE’s climate is considered one of the hottest and humid regions in the world, making air conditioning systems essential in each house nearly all year long. Air-conditioning systems consume most of the buildings’ electricity and that comes at a hefty energy cost. Therefore, any serious improvements in this technology in reducing the needed cooling load will lead to economical gain. Different parameters affect the cooling load of a building including the type of air conditioning system (centralized or decentralized units), the outdoor temperature and humidity, and the orientation of the building. Proper building orientation in Malaysia lead to 7.9% cooling load saving. The aim of this work is to study the effect of building orientation located in UAE on the cooling load. A single room is considered as the baseline building and TRNSYS software is used to calculate its cooling load when oriented to north, west, north–west, and south. The ASHRAE Standard 55 is adopted where the zone temperature ranges between 20°C – 25°C, and the relative humidity between and 40 – 60%. The study concludes that when the room is oriented to north–west the cooling load was at the minimum of 2627 Ton-hr. Whereas the maximum cooling load occurs when the room was oriented to west at 3161 Ton-hr. This led to nearly 17% cooling load saving. Therefore, it is recommended to orient buildings facing the north–west direction in the UAE. read more... read less...
Keywords: Cooling Load, Building Orientation, Air-Conditioning
A shelf-life model considering mechanical injury and natural decay to optimize fresh fruit distribution
IJTEE, Volume-18 , Issue 2 (2021), PP 89 - 99
Published: 02 Sep 2021
DOI: 10.5383/ijtee.18.02.005
by Damrongpol Kamhangwong, Aicha Sekhari, Gilles Neubert from Université Lumière Lyon 2, Lyon, France and Emlyon Business School, Saint-Étienne, France.
Abstract: This paper develops a specific quality attribute model considering mechanical injury (MI) and natural decay (ND) in fresh fruit, for problem solving in operations research. The model resolves shortcomings found in the widely adopted models mainly focused on a set or an undetermined shelf life, through a multi-objective framework designed to study the economic benefits of fresh fruit distribution. The multi-objective optimization model integrates the transportation and inventory planning of fresh fruit (MOTIP). It is based on a bi-objective function maximizing the total net profit (NP) and the percentage of the remaining fruit quality (%RQ), using a Non-Dominated Sorting Genetic Algorithm II (NSGA-II) to solve the problem. The results indicate the accuracy of NSGA-II algorithm to solve the problem of fresh fruit distribution. The optimal Pareto front curves of the TIP model show a strong positive correlation between the %RQ and the NP. While the specific kinetic shelf-life model can be used to decide on the best schedule for transporting and storing fruit in order to optimize the net profit and remaining quality, the MOTIP-model allows a significant improvement in the benefits related to the export of fresh fruit while minimizing the loss of quality. The developed model is a decision support tool that allows exporters to better plan the transport and storage of exported fresh fruits. read more... read less...
Keywords: fresh fruit quality; fresh fruit distribution; shelf-life model; quality loss; multi-objective decision-making
Numerical simulation of multiphase flow at fracture intersections
IJTEE, Volume-18 , Issue 2 (2021), PP 79 - 88
Published: 02 Sep 2021
DOI: 10.5383/ijtee.18.02.004
by Wenjuan Zhang, Isam Janajreh, Mohammed Al Kobaisi from Department of petroleum engineering, Khalifa University of Science and Technology, Abu Dhabi, UAE and Department of Mechanical Engineering, Khalifa University of Science and Technology, Abu Dhabi, UAE
Abstract: Various models of simulating immiscible multiphase flow in a simple fracture intersection is compared numerically in this work. The first two models assume that the fractures can be treated as a type of porous media and fluid flow in fractures is therefore governed by Darcy’s law. The fractures are either gridded explicitly (equal-dimensional porous fracture model) to account for the fracture intersection or they are simplified as lower-dimensional entities (lower-dimensional porous fracture model) and fracture intersection is eliminated in the computational domain by using the star-delta transformation. Numerical results of equal-dimensional porous fracture model demonstrate that fracture intersection angle and the scale ratio of fracture length to fracture aperture can impact the multiphase flow behavior at fracture intersections but the effects of these factors cannot be captured by the lower-dimensional porous fracture model. A CFD study is then conducted to gain better insight into the problem by solving the Navier-Stokes equation coupled with Volume of Fluid (VOF) method. The results show that viscosity of the two phases can affect flow at the fracture intersection. When the two phases have the same viscosity, the equal-dimensional porous fracture model agrees qualitatively with CFD results but the porous fracture model is much more sensitive to viscosity contrast than what is predicted by CFD simulation. read more... read less...
Keywords: Fracture modeling, Darcy’s law,Navier-Stokes equation, volume of fluid
Comparative Life Cycle Assessment of Paper and Computer Based Exams
IJTEE, Volume-18 , Issue 2 (2021), PP 71 - 77
Published: 02 Sep 2021
DOI: 10.5383/ijtee.18.02.003
by Muhammad Imran, Salah Elaskari, Abdulmajeed Eid Albalawi from University of Tabuk, Tabuk, Saudi Arabia, 71491 and American International University, Al Jahra, Kuwait
Abstract: Universities around the globe consume large number of papers every year for educational and administrative purposes. A major portion of these papers are consumed for exam purpose only. Post Covid -19, several universities have moved to computer-based exams because of health and safety concerns. The purpose of this article is to compare paper and computer-based exams primarily from the perspective of their impact on the environment. Our main aim is to perform Life Cycle Assessment (LCA) for three scenarios and find out which one of them is better from the environmental perspective. The three scenarios that have been considered for LCA modelling are as follows: (1) consumed papers go to landfill, (2) consumed papers are recycled, and (3) switching to computer-based exams. The procedure of conducting the LCA follows the ISO 14040 standard method which consists of four steps: (1) goal and scope definition, (2) inventory analysis, (3) impact assessment and (4) interpretation. This research uses GaBi educational software tool for LCA modeling and considers Global Warming Potential (GWP) as the impact category for comparison purpose. A further comparison from student performance point of view has also been made at the end of the article. The result of this research shows that computer-based exams have least impact on the environment based on the selected GWP impact category as compared to paper-based exams. Furthermore, it has been found that there is no significant student performance difference in either type of these exams. read more... read less...
Keywords: LCA; Paper-based exam; Computer-based exam; Environmental impact
Experimental Investigation of Remote Vibration Sensing with Locally-Powered Devices
IJTEE, Volume-18 , Issue 2 (2021), PP 70 - 70
Published: 02 Sep 2021
DOI: 10.5383/ijtee.18.02.002
by Saeed k. Al Nuaimi, Manish K. Singh from Department of Mechanical and Aerospace Engineering, United Arab Emirates University, Al Ain, UAE and Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis MN 55455,USA
Abstract: Self-power sensors at multiple places in a network will be required for advanced wireless communication infrastructure, which comprises remote sensing technologies, networks, and data management. It is still difficult to power these sensors and their related transmitters or receivers. Local energy harvesting presents a chance to mitigate or eliminate the impact of this problem as an enabling technology. We create a self-powered real-time point-to-point wireless communication system, also known as transmission power self-optimization, that adapts the transmission power of a specific node in a wireless sensor network to the requirements. The transmitter module co-located with a vibrating object harvests and stores energy from vibration through piezoelectric components. Even when the vibrating source has very little energy, the collected energy allows for reliable wireless communication. The proposed system is discussed in detail, and data on voltage sensing, harvested power storage, and current are examined. read more... read less...
Keywords: Smart sensors; Energy harvesting;Internet of Things; Vibration sensing; Wireless transmission
RANS Based Numerical Simulation of Horizontal Axis Wind Turbine
IJTEE, Volume-18 , Issue 2 (2021), PP 57 - 63
Published: 02 Sep 2021
DOI: 10.5383/ijtee.18.02.001
by Liu Su, Isam Janajreh from Department of Mechanical Engineering, Khalifa University, Abu Dhabi, UAE
Abstract: A three-dimensional (3D) Computational Fluid Dynamics (CFD) model has been developed in this work to study 3.5kW Horizontal Axis Wind Turbine (HAWT). The model is based on the incompressible Navier-Stokes flow that accounts for the turbulence via SST k-ω turbulence model in a Single Rotating Reference Frame (SRF) that considers the rotor rotation. A body-fitted multi-block mesh is constructed around the turbine rotor with high-resolution mesh in the high-velocity gradient regions and in conjunction with the standard law of the wall next to the blade surface. The mod el comprises 4.5 million hexahedral elements; the blade is specifically wrapped in an O-grid boundary layer to achieve the desirable y+ value (<60). The flow around the blade was studied in detail (velocity, pressure, etc.) and results of the power coeffic ients were compared to the experimental data, which showed a plausible trend. The developed procedures can be easily and economically applied to any given HAWT configuration making the CFD a virtual wind tunnel in another complex atmospheric boundary layer flow. In view of these results, 2D blade mode is also developed and the power coefficient (Cp) values for the two models are compared. The results emphasized the role of rotation and radial momentum and demonstrated large discrepancies in the attained blade pressure values. read more... read less...
Keywords: CFD, HAWT, SRF, SST k -ω, Wall modeling
Investigating the Potential of Salinity Gradient Solar Pond as a Thermal Energy Storage System for Lahore Pakistan
IJTEE, Volume-18 , Issue 2 (2021), PP 101 - 105
Published: 23 Aug 2022
DOI: 10.5383/ijtee.18.02.006
by Muhammad Ali, Ussama Ali, Muhammad Tayyab Qureshi, Muhammad Lolak from The University of Lahore, Lahore, Pakistan and University of Engineering and Technology, Lahore, Pakistan
Abstract: This work is an attempt to experimentally study the ability of solar pond to store the thermal energy in the form of heat, and to explore the potential of solar energy and the prospects of solar ponds in Pakistan. A brief overview of the energy mix of Pakistan. Solar pond was built using a water tank of 300-galons. Halogen lamps were used to provide the heat and to resemble the sun’s radiations. The temperature of upper convective zone (UCZ) and lower convective zone (LCZ) was recorded for 100 hours. A maximum temperature of 66°C was recorded for LCZ, while that for UCZ was almost 40°C. Cyclic variations occurred in the temperature measurements of both zones which occurred with a time perio d of 24 hours which showed that the variation was due to the variants in the ambient weather conditions. This study provided short overview on the prospect of solar pond to store solar thermal energy which can then be utilized for various domestic/commercial activities. read more... read less...
Keywords: Solar thermal energy, Salinity gradient, Solar pond; Energy mix, Thermal storage