Browsing by Author "Amini, Ali"

Now showing 1 - 5 of 5

Citation - WoS: 12
Citation - Scopus: 15
Developing an Infrared-Assisted Solar Drying System Using a Vertical Solar Air Heater With Perforated Baffles and Nano-Enhanced Black Paint
(Pergamon-elsevier Science Ltd, 2023) Tuncer, Azim Dogus; Amini, Ali; Khanlari, Ataollah
In the present study, it is aimed to improve the performance of a solar drying system (SDS) utilizing ZnO nano-enhanced absorber coating and infrared heating system. In the first stage of this work, different geometrical configurations of the main heating system of the SDS which is a vertical solar air heater (VSH) have been numerically analyzed. According to the numerical findings, VSH with perforated type baffles gave the best performance results. Then, the determined configuration has been manufactured and combined with a drying chamber. Moreover, two other modifications have been applied to the system including an infrared heater and nano-enhanced black paint. In other words, the experimental part of this research contains three SDS types including a conventional SDS, a SDS with infrared heater and a SDS with infrared heater and ZnO nano-enhanced absorber coating (combined usage of two modifications). The mean thermal and exergetic efficiencies of the VSH analyzed within the scope of this work were attained between 53.54-65.12% and 9.94-14.32%, respectively. Moreover, combined use of infrared heater and nano-enhanced absorber coating material in the VSH decreased the drying time period as 43.75% when compared to the unmodified SDS.
Citation - WoS: 19
Citation - Scopus: 18
Experimental and Numerical Analysis of a Helically-Coiled Solar Water Collector at Various Angular Placements
(Elsevier France-editions Scientifiques Medicales Elsevier, 2023) Variyenli, Halil Ibrahim; Amini, Ali; Tuncer, Azim Dogus; Khanlari, Ataollah; Kolay, Sahin
Solar water collectors are widely utilized for providing hot water to be used in different applications. In this work, a solar water collector with a helically coiled absorber has been designed, fabricated, and examined at different test conditions to specify its overall performance. One of the major goals of using a tube-type absorber is to upgrade the thermal efficiency of the collector by providing a perpendicular angle between the absorber and incident solar rays. Also, using a helically-coiled structure make it possible to increase the absorber surface in a relatively small volume in comparison to conventional solar water collectors. In the first step of this research, the designed helically-coiled solar collector has been simulated using a solar radiation model. In the next step, the manufactured helically-coiled solar collector has been experimentally tested at three different inclination angles and various water flow rates. According to the experimental results, mean thermal efficiencies of horizontal, vertical, and angular helically-coiled collectors were obtained in the ranges of 29.48-48.23%, 27.17-47.03%, and 32.50-52.71%, respectively. In addition, sustainability index values for horizontal, vertical and angular helically-coiled collectors were achieved between the ranges of 1.0041-1.0091, 1.0039-1.0087, and 1.0043-1.0102, respectively. Moreover, the maximum deviation between numerical and experimental findings was calculated as 14%.
Citation - WoS: 28
Citation - Scopus: 34
Experimental and Transient Cfd Analysis of Parallel-Flow Solar Air Collectors With Paraffin-Filled Recyclable Aluminum Cans as Latent Heat Energy Storage Unit
(Elsevier, 2023) Tuncer, Azim Dogus; Amini, Ali; Khanlari, Ataollah
In the present study, it is aimed to improve the overall performance of a parallel-flow solar air collector (PSC) using phase change material (PCM)-based latent heat energy storage unit and recyclable materials. In the simulation part of this work, two PSCs including a collector without modification and a collector equipped with PCM filled aluminum cans have been analyzed. The simulation part of the current work is handling the flow of air through the collectors and melting-solidification of PCM material inside the aluminum cans. Considering the simulation study results, three different PSC configurations have been manufactured including an unmodified PSC, a PSC with PCM-filled aluminum cans on the front side of the absorber and a PSC with PCM-filled aluminum cans on both sides (back and front) of the absorber surface. According to the results of the analyses, utilizing PCM-filled aluminum cans in both surfaces of the absorber plate of the PSC improved numerically and experimentally obtained exergetic efficiency values as 61.70% and 74.03%, respectively. Moreover, enviro-economic analysis has been conducted within the scope of this work. The payback periods of the analyzed systems were between 2.17 and 2.43 years. Employing PCM in the both sides of the absorber surface decreased the payback time of the system as 10.69% in comparison to the conventional PSC. Moreover, using PCMs on the single and double side of the absorber plate improved the annual carbon dioxide savings as 22.68% and 35.42%, respectively.
A Lithium-Ion Battery Fast Charging Algorithm Based on Electrochemical Model: Experimental Results
(Amer Soc Mechanical Engineers, 2024) Anwar, Sohel; Pramanik, Sourav; Amini, Ali
Lithium-Ion batteries have become the principal battery technology for EVs to date. However, one of the principal factors limiting the widespread usage of the EVs is the length of charging times for the lithium-ion battery packs. The appropriate charging algorithm is critical to shorten the battery charging times while keeping the battery safe. In our earlier work, we proposed a novel optimal strategy for charging the lithium-ion battery based on electrochemical battery model using A performance index that aimed at achieving a faster charging rate while maintaining safe limits for various battery parameters. A more realistic model, based on battery electro-chemistry has been used for the design of the optimal charging algorithm as opposed to the conventional equivalent circuit models. Simulation results showed that the proposed optimal charging algorithm is capable of shortening the charging time of a lithium-ion cell by as much as 30% when compared with the standard constant current charging. Here we present the results from a number of experiments using Lithium-Ion cylindrical cells that were charged using the proposed algorithm and compared the charging times with the standard constant current-constant voltage (CC-CV) charging algorithms. A Maccor Series 4300 battery testing system was used to carry out the experiments. The experimental results showed that the proposed algorithm offered shorter charging times by up to 16% when compared to the CC-CV charging algorithms under the same battery initial conditions such as SOC and temperature of the cells.
Citation - WoS: 5
Citation - Scopus: 4
Parameter Identification and Speed Control of a Small-Scale BLDC Motor: Experimental Validation and Real-Time PI Control with Low-Pass Filtering
(MDPI, 2025) Abouseda, Ayman Ibrahim; Doruk, Resat Ozgur; Amini, Ali
This paper presents a structured and experimentally validated approach to the parameter identification, modeling, and real-time speed control of a brushless DC (BLDC) motor. Electrical parameters, including resistance and inductance, were measured through DC and AC testing under controlled conditions, respectively, while mechanical and electromagnetic parameters such as the back electromotive force (EMF) constant and rotor inertia were determined experimentally using an AVL dynamometer. The back EMF was obtained by operating the motor as a generator under varying speeds, and inertia was identified using a deceleration method based on the relationship between angular acceleration and torque. The identified parameters were used to construct a transfer function model of the motor, which was implemented in MATLAB/Simulink R2024b and validated against real-time experimental data using sinusoidal and exponential input signals. The comparison between simulated and measured speed responses showed strong agreement, confirming the accuracy of the model. A proportional-integral (PI) controller was developed and implemented for speed regulation, using a low-cost National Instruments (NI) USB-6009 data acquisition (DAQ) and a Kelly controller. A first-order low-pass filter was integrated into the control loop to suppress high-frequency disturbances and improve transient performance. Experimental tests using a stepwise reference speed profile demonstrated accurate tracking, minimal overshoot, and robust operation. Although the modeling and control techniques applied are well known, the novelty of this work lies in its integration of experimental parameter identification, real-time validation, and practical hardware implementation within a unified and replicable framework. This approach provides a solid foundation for further studies involving more advanced or adaptive control strategies for BLDC motors.