Entropy generation analysis of nanofluid heat transfer in dimpled heat exchangers Bahjat Hassan Alyas, Firas Aziz Ali, Ayad S. Abedalh, Thamir A. D. M. S. Almula Canadian Journal of Chemical Engineering, 2026 Enhancing thermal performance while minimizing thermodynamic losses in compact heat exchangers remains a critical challenge in modern energy systems, with limited understanding of synergistic effects between dimpled surfaces and nanofluids, particularly regarding entropy generation characteristics. This study investigates how shallow dimpled geometries (depth‐to‐diameter ratios δ / D = 0.1–0.3) combined with Al 2 O 3 –water and CuO–water nanofluids influence entropy generation patterns and identifies optimal configurations that minimize irreversibilities while maximizing heat transfer performance. Computational fluid dynamics simulations coupled with second‐law thermodynamic analysis were performed across Reynolds numbers 500–3000 and nanoparticle volume fractions 0%–4%, with comprehensive validation against published data (deviations <5%). Results demonstrate that shallow dimples with δ / D = 0.1–0.2 achieve 18%–25% reduction in total entropy generation compared to smooth channels, with optimal performance at Re = 1500–2500. Al 2 O 3 nanofluids at 2%–4% concentration exhibit superior thermodynamic performance (thermal conductivity ratios 1.12–1.18 vs. 1.08–1.14 for CuO). Bejan number analysis reveals transition from thermal‐dominated to viscous‐dominated irreversibility. This research establishes comprehensive design correlations and scaling laws enabling entropy‐optimized selection of geometric parameters and nanofluid specifications for thermodynamically superior compact thermal management systems.
Experimental and numerical analysis of hydrothermal behavior for different nanofluids in a shallowly dimpled tube heat exchanger Ayad S. Abedalh, Bahjat Hassan Alyas, Firas Aziz Ali, Thamir A. D. M. S. Almula Environmental Progress and Sustainable Energy, 2026 Heat exchangers require improved thermal efficiency for power generation, chemical processing, and electronics cooling applications. While dimpled surfaces and nanofluids have been studied separately, their combined implementation and synergistic mechanisms remain poorly understood. This study experimentally and numerically investigates aluminum oxide, copper oxide, and titanium dioxide nanofluids at 0.5%–2.0% concentrations in shallowly dimpled copper tubes. Hemispherical dimples with depth‐to‐diameter ratios of 0.1–0.3, diameters of 4–8 mm, and pitch‐to‐diameter ratios of 0.8–1.6 were tested across Reynolds numbers of 4000–20,000. Copper oxide nanofluid at 1.5% concentration in optimally configured dimpled tubes achieved 85.3% heat transfer enhancement compared to water in smooth tubes, with a thermal performance factor of 1.83. This substantially exceeded individual contributions of 34% for nanofluids alone and 38% for dimpled tubes alone, confirming strong synergistic effects. Flow visualization revealed dimple‐generated vortices intensify nanoparticle microscale transport through simultaneous boundary layer disruption and enhanced thermal conductivity. Optimal configurations maintained 52% pressure penalties while nearly doubling heat transfer rates. Empirical correlations from 180 data points predicted performance within 7% accuracy. This research quantifies synergistic effects between geometric enhancement and nanofluid technology, provides validated design correlations, and elucidates underlying mechanisms, enabling next‐generation compact heat exchangers for energy‐intensive applications.
Comparative Analysis of Fuzzy Logic, PID, and FOPID Controllers in DC Microgrid Voltage Regulation for Power Plants: Integrating Renewable Energy Sources Waseem Kh. Ibrahim, Fawaz S. Abdullah, Firas Aziz Ali Journal of Advanced Research in Applied Mechanics, 2025 The worldwide direction moving towards sustainable energy solutions requires more advanced control mechanisms within power systems, especially in DC microgrids that combine renewable energy sources like solar panels and wind turbines with conventional power setups. This paper addresses the necessary challenge of maintaining steady and efficient DC voltage control—important for the dependability and performance of power plants. Specifically, it looks at the efficiency of four different control strategies: classic PID (Proportional-Integral-Derivative) controllers, Fuzzy Logic Controllers (FLC), Fractional Order PID (FOPID) controllers, and a new mixed system that merges Fuzzy Logic with PID controllers in a Fuzzy-PI layout. Our approach utilizes a strict comparative analysis using MATLAB Simulink simulations, assessing each controller’s capacity to manage dynamic load shifts, adjust to the unpredictability of renewable energy inputs, and preserve strong voltage stability under various operational cases. The simulations are crafted to single out the most effective control strategy to boost efficiency and toughness in microgrid operations. This study adds substantially to the progress of control strategies in hybrid energy systems, offering important insights into the creation of more complex and reliable power management solutions. By evaluating the performance of these varied controllers, we aim to underline potential upgrades in control systems that could support better energy management in intricate grid setups, thereby encouraging the wider inclusion of renewable energy technologies into power grids.
EXPERIMENTAL COMPARISON OF THERMAL PERFORMANCE BETWEEN V-CORRUGATED AND FLAT PLATE SOLAR COLLECTORS International Journal on Technical and Physical Problems of Engineering, 2023
Friction Factor and Heat Transfer Enhancement of Hybrid Nanofluids in a Heated Circular Tube Firas Aziz Ali, Adnan M. Alsaffawi International Journal of Heat and Technology, 2023 This work investigates the potential of hybrid nanoparticles suspended in pure water to enhance the thermal performance of heat exchangers at minimal weight fractions. A hybrid nanofluid consisting of 50% ZnO and 50% Al 2 O 3 nanoparticles dispersed in pure water at weight fractions of 0.1%, 0.3%, and 0.5% was prepared. An experimental rig, featuring a straight horizontal tube with a constant wall heat flux, was equipped with eight thermocouples positioned at the inlet, outlet, and along the tube's surface. The study focuses on the impact of the hybrid nanofluid on the friction factors and heat transfer coefficients within a Reynolds number range of 5000 to 20000. Observations indicate that the Nusselt number escalates with an increase in the Reynolds number through the horizontal tube, while the friction factor exhibits a converse relationship. The peak Nusselt number and friction factor were observed at a 5% mass fraction of the hybrid nanofluid. Specifically, enhancements in the Nusselt number were recorded at 9%, 11.8%, and 16.7% for the weight fractions of 0.1%, 0.3%, and 0.5% respectively. Additionally, the deviation in the friction factor was noted at 2.3%, 3.6%, and 4.1% in comparison to pure water. This study thus provides critical insights into the role of hybrid nanofluids in optimizing heat transfer in heat exchangers.
The impact of alumina nanoparticles suspended in ethylene glycol on the performance efficiency of a double pipe heat exchanger Firas Aziz Ali, Adnan M. Alsaffawi, Karam Hashim Mohammed Frontiers in Heat and Mass Transfer, 2020 The augmentation of the heat transfer in heat exchangers is one of the methods to increase efficiency of the system. The double tube heat exchanger is selected to many suitable techniques of heat transfer enhancement. In this study; the friction factor and heat transfer coefficient of double tube is evaluated experimentally. The Al2O3 nanoparticles dispersed in ethylene glycol (EG) with a diameter 50 nm and the weight concentration (0.1%, 0.3%, 0.5%, 0.7%, 1%) has been utilized. Then the effect of parallel current and counter current with different ranges of Reynolds number (10,000 to 30,000) on the friction factor and heat transfer coefficient experimentally examined then selected the best current flow. Thermophysical properties (density, viscosity) are measured and validated with experimental data of the other researches. Result showed that the friction factor decreases with increasing of Reynolds number and increases with increasing of weight concentration but Nusselt number increases with increasing of Reynolds number and concentration of weight. It was concluded that the utilizing of alumina nanoparticles suspended in EG through a double pipe heat exchanger is significant enhancement of heat transfer. The results indicate that the alumina dispersed in EG nanofluid can enhance thermophysical properties of EG to 20%. Likewise, the friction factor is slightly higher than that of pure EG and the nanofluid heat transfer is higher than the pure EG.
Estimation the Effects of each site factors, time factors, and optical factors on absorbed solar radiation value that incident on a flatplate solar collector Journal of Theoretical and Applied Information Technology, 2012
RECENT SCHOLAR PUBLICATIONS
Entropy generation analysis of nanofluid heat transfer in dimpled heat exchangers BH Alyas, FA Ali, AS Abedalh, TA Almula The Canadian Journal of Chemical Engineering , 2026 2026
Experimental and numerical analysis of hydrothermal behavior for different nanofluids in a shallowly dimpled tube heat exchanger AS Abedalh, BH Alyas, FA Ali, TA Almula Environmental Progress & Sustainable Energy, e70376 , 2026 2026 Citations: 1
A Comparative Study on the Cooling Performance of a Split Air Conditioning System Using Nano-Lubricant and Hybrid Nano-Lubricant FAA Mustafa W. Hamadalla, Sohaib N. Abdullah Journal of Nanostructures 16 (1), 649-658 , 2026 2026
Performance Enhancement of Photovoltaic Panels Using Open-Loop and Closed-Loop Water-Based Cooling Systems: An Experimental Study MM Ali, FA Ali International Conference on Sustainable Development Techniques, 649-667 , 2024 2024
Enhancing thermal efficiency in solar water heaters using reflective mirrors QJ Abdul-Ghafoor, F Ali, WK Hasan, KA Hammoodi, HS Majdi International Journal of Design and Nature and Ecodynamics 19 (1), 31-39 , 2024 2024 Citations: 4
Comparative Analysis of Fuzzy Logic, PID, and FOPID Controllers in DC Microgrid Voltage Regulation for Power Plants: Integrating Renewable Energy Sources WK Ibrahim, FS Abdullah, FA Ali Journal of Advanced Research in Applied Mechanics 128 (1), 50-61 , 2024 2024 Citations: 3
Friction Factor and Heat Transfer Enhancement of Hybrid Nanofluids in a Heated Circular Tube AMA Firas Aziz Ali International Journal of Heat and Technology 41 (5), 1383-1388 , 2023 2023 Citations: 5
EXPERIMENTAL COMPARISON OF THERMAL PERFORMANCE BETWEEN V-CORRUGATED AND FLAT PLATE SOLAR COLLECTORS AHS Adnan M. Alsaffawi , Firas Aziz Ali International Journal on “Technical and Physical Problems of Engineering … , 2023 2023 Citations: 2
Performance analysis of Pelton turbine under different operating conditions: An experimental study FAA Omar Rafae Alomar, Hareth Maher Abd, Mothana M. Mohamed Salih Ain Shams Engineering Journal 13 (4), 101684-101692 , 2022 2022 Citations: 45
Experimental study of compound parabolic concentrator with flat plate receiver HM Abd, OR Alomar, FA Ali, MMM Salih Applied Thermal Engineering 166, 114678 , 2020 2020 Citations: 63
THE IMPACT OF ALUMINA NANOPARTICLES SUSPENDED IN ETHYLENE GLYCOL ON THE PERFORMANCE EFFICIENCY OF A DOUBLE PIPE HEAT EXCHANGER Firas Aziz Ali, Adnan M. Alsaffawi, Karam Hashim Mohammed Frontiers in Heat and Mass Transfer 15 (21), 1-7 , 2020 2020 Citations: 6
An experimental investigation of a double pass solar air heater performance: A comparison between natural and forced air circulation processes MMM Salih, OR Alomar, FA Ali, HM Abd Solar Energy 193, 184-194 , 2019 2019 Citations: 99
Optimum tilt angle of photovoltaic panels for some Iraq cities FA Ali Journal of University of Babylon for Engineering Sciences 26 (1), 155-163 , 2018 2018 Citations: 16
Evaluation of the Best Slope Angle for a Flat-Plate Solar Collector F Aziz Ali Kirkuk Journal of Science 12 (4), 157-178 , 2017 2017 Citations: 3
Estimation of Hourly Solar Radiation Using ASHRAE Clear-Sky Model for Baghdad City NMA Firas Aziz Ali second engineering scientific conference at the College of Engineering … , 2013 2013
Estimation of the effects of each site factors, time factors, and optical factors on absorbed solar radiation value that is incident on a flat-plate solar collector FS Abdullah, FA Ali Journal of Theoretical and Applied Information Technology 41 (2), 122-133 , 2012 2012 Citations: 6
Computation of solar radiation on horizontal surface over some Iraqi cities FA Ali Engineering and Technical Journal 29 (10), 2026-2042 , 2011 2011 Citations: 9
MOST CITED SCHOLAR PUBLICATIONS
An experimental investigation of a double pass solar air heater performance: A comparison between natural and forced air circulation processes MMM Salih, OR Alomar, FA Ali, HM Abd Solar Energy 193, 184-194 , 2019 2019 Citations: 99
Experimental study of compound parabolic concentrator with flat plate receiver HM Abd, OR Alomar, FA Ali, MMM Salih Applied Thermal Engineering 166, 114678 , 2020 2020 Citations: 63
Performance analysis of Pelton turbine under different operating conditions: An experimental study FAA Omar Rafae Alomar, Hareth Maher Abd, Mothana M. Mohamed Salih Ain Shams Engineering Journal 13 (4), 101684-101692 , 2022 2022 Citations: 45
Optimum tilt angle of photovoltaic panels for some Iraq cities FA Ali Journal of University of Babylon for Engineering Sciences 26 (1), 155-163 , 2018 2018 Citations: 16
Computation of solar radiation on horizontal surface over some Iraqi cities FA Ali Engineering and Technical Journal 29 (10), 2026-2042 , 2011 2011 Citations: 9
THE IMPACT OF ALUMINA NANOPARTICLES SUSPENDED IN ETHYLENE GLYCOL ON THE PERFORMANCE EFFICIENCY OF A DOUBLE PIPE HEAT EXCHANGER Firas Aziz Ali, Adnan M. Alsaffawi, Karam Hashim Mohammed Frontiers in Heat and Mass Transfer 15 (21), 1-7 , 2020 2020 Citations: 6
Estimation of the effects of each site factors, time factors, and optical factors on absorbed solar radiation value that is incident on a flat-plate solar collector FS Abdullah, FA Ali Journal of Theoretical and Applied Information Technology 41 (2), 122-133 , 2012 2012 Citations: 6
Friction Factor and Heat Transfer Enhancement of Hybrid Nanofluids in a Heated Circular Tube AMA Firas Aziz Ali International Journal of Heat and Technology 41 (5), 1383-1388 , 2023 2023 Citations: 5
Enhancing thermal efficiency in solar water heaters using reflective mirrors QJ Abdul-Ghafoor, F Ali, WK Hasan, KA Hammoodi, HS Majdi International Journal of Design and Nature and Ecodynamics 19 (1), 31-39 , 2024 2024 Citations: 4
Comparative Analysis of Fuzzy Logic, PID, and FOPID Controllers in DC Microgrid Voltage Regulation for Power Plants: Integrating Renewable Energy Sources WK Ibrahim, FS Abdullah, FA Ali Journal of Advanced Research in Applied Mechanics 128 (1), 50-61 , 2024 2024 Citations: 3
Evaluation of the Best Slope Angle for a Flat-Plate Solar Collector F Aziz Ali Kirkuk Journal of Science 12 (4), 157-178 , 2017 2017 Citations: 3
EXPERIMENTAL COMPARISON OF THERMAL PERFORMANCE BETWEEN V-CORRUGATED AND FLAT PLATE SOLAR COLLECTORS AHS Adnan M. Alsaffawi , Firas Aziz Ali International Journal on “Technical and Physical Problems of Engineering … , 2023 2023 Citations: 2
Experimental and numerical analysis of hydrothermal behavior for different nanofluids in a shallowly dimpled tube heat exchanger AS Abedalh, BH Alyas, FA Ali, TA Almula Environmental Progress & Sustainable Energy, e70376 , 2026 2026 Citations: 1
Entropy generation analysis of nanofluid heat transfer in dimpled heat exchangers BH Alyas, FA Ali, AS Abedalh, TA Almula The Canadian Journal of Chemical Engineering , 2026 2026
A Comparative Study on the Cooling Performance of a Split Air Conditioning System Using Nano-Lubricant and Hybrid Nano-Lubricant FAA Mustafa W. Hamadalla, Sohaib N. Abdullah Journal of Nanostructures 16 (1), 649-658 , 2026 2026
Performance Enhancement of Photovoltaic Panels Using Open-Loop and Closed-Loop Water-Based Cooling Systems: An Experimental Study MM Ali, FA Ali International Conference on Sustainable Development Techniques, 649-667 , 2024 2024
Estimation of Hourly Solar Radiation Using ASHRAE Clear-Sky Model for Baghdad City NMA Firas Aziz Ali second engineering scientific conference at the College of Engineering … , 2013 2013
