Article
Thermodynamics
Hao Ma, Boshu He, Liangbin Su, Di He
Summary: This study investigates the laminar nanofluid flow and convective heat transfer at the entry region of microtubes under constant wall temperature and constant heat flux boundary conditions. The results show that the entrance effect dominates pressure drop and thermal performance of the nanofluids near the entrance of the channel, while the influences of particle concentration and particle size gradually become evident as the axial distance increases.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Sreenivasulu Reddy Goda, Ramasamy Kalaivanan, Rampelli Uday Kumar, Prakash H. Jadhav
Summary: This study conducted experimental and numerical investigations on cerium oxide (CeO2) nanofluid to estimate its thermo-hydrodynamic performance in twin tube counter flow heat exchangers (TTCFHEs). The study found that the outlet temperature of the cold fluid increases with increasing concentrations of CeO2 nanofluids, while it decreases with increasing flow Reynolds number. The average Nusselt number (Nu) for 0.3% and 0.2% CeO2 nanofluid showed significant improvements compared to the base fluid, while the performance evaluation criteria (PEC) increased with increasing nanofluid concentrations.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Thermodynamics
Asif Afzal, Md Tariqul Islam, Abdul Razak Kaladgi, A. Muthu Manokar, Olusegun D. Samuel, M. A. Mujtaba, Manzoore Elahi M. Soudagar, H. Fayaz, Hafiz Muhammad Ali
Summary: The study investigates the thermal performance of a helical tube three-fluid heat exchanger using graphene/water nanofluids, showing an increase in overall heat transfer coefficient with higher fluid flow rates and variation in effectiveness due to different fluid flow speeds. Comparison with a double-pipe helical tube heat exchanger reveals significant differences in Nusselt numbers and correlations. Semiempirical correlations proposed for the triple-fluid helical tube heat exchanger align well with experimental results and are useful for multiple fluid flows and thermal communications in heat exchangers.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
Mehdi Salari, Mohammad Reza Assari, Ashkan Ghafouri, Nader Pourmahmoud
Summary: The heat transfer characteristics of MgO-EG nanofluid flowing in a double tube heat exchanger with a partial porous material were experimentally investigated. The results showed that using nanofluid and porous media significantly improved heat transfer. The use of partial porous media is recommended to enhance the thermal performance of heat exchangers in industrial applications.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Engineering, Aerospace
Wen-Chung Wu, Ankit Kumar
Summary: In this study, the flow characteristics of nanofluid over a backward facing step at low Reynolds number were numerically investigated, and the heat transfer was analyzed. The results showed that the use of nanofluid increased the heat transfer coefficient and Nusselt number, while decreasing the coefficient of skin friction and outlet temperature.
Article
Engineering, Multidisciplinary
Kai Tang, Mohammad Amin Masoumi, Hamid Rajabi, Seyed Alireza Rozati, Omid Ali Akbari, Farnaz Montazerifar, Davood Toghraie, Mohammad Khalili
Summary: This paper presents a numerical simulation study of graphene nanoplatelet (GNP) - sodium dodecylbenzene sulfonate (SDBS) - water nanofluid. The study indicates that higher Reynolds numbers lead to increased convective heat transfer coefficients, decreased temperature gradients, and increased influence of cooling fluid temperature in the warm areas near the solid wall. Furthermore, higher Reynolds numbers also result in larger development lengths and decreased outlet section temperatures.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Civil
Andrea Orlando, Luisa Pagnini, Maria Pia Repetto
Summary: This paper evaluates and discusses the aerodynamic properties of a 16-sided polygonal cylinder with imperfections and ancillaries investigated by wind tunnel tests. The results provide an estimate of the aerodynamic coefficients for this type of elements, quantify the influence of geometrical and flow properties on the aerodynamic behavior, and point out the sensitivity of such polygonal cross-section to galloping instability.
ENGINEERING STRUCTURES
(2023)
Article
Thermodynamics
Balaga Ravikiran, Koona Ramji, Tunuguntla Subrahmanyam
Summary: This study investigates the thermal performance of a combination of twisted tapes, perforated twisted tapes, and wire coils in a circular tube with water as the working fluid under turbulent flow conditions. The results show that these combined effects can significantly enhance the convective heat transfer coefficient and friction factor by mechanisms such as reversed flow, swirling flow, and impinging flow, ultimately improving the thermal performance of the circular tube.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Seyedmahmood Kia, Shoaib Khanmohammadi, Ali Jahangiri
Summary: In this study, the heat transfer and pressure drop properties of Al2O3 and SiO2/Base oil nanofluid flow in a helical tube were investigated numerically and experimentally. The impact of various parameters, including flow Reynolds number, fluid temperature, nanoparticles, and weight concentrations, on the heat transfer factor and pressure drop was analyzed. The results showed that nanofluid enhanced the heat transfer factor and pressure drop compared to the base fluid. The Al2O3 nanofluid exhibited higher heat transfer coefficient than the SiO2 nanofluid. The maximum heat transfer rate was achieved with 0.5% mass concentrations of Al2O3 and SiO2 nanofluids. The helical tube geometry improved heat transfer by 19.5%, and reducing helical pitch and pitch circle diameter further enhanced the heat transfer.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Engineering, Chemical
Peymaneh Dehghan, Fatemeh Keramat, Masoud Mofarahi, Chang-Ha Lee
Summary: This study investigates the effects of an inclined step combined with different types of obstacles on the heat transfer of graphene oxide nanofluid inside a double backward-facing microchannel. The simulation results show that placing a triangular obstacle at the top of the first step significantly increases the Nusselt number and heat transfer coefficient compared to pure water. High pressure drop improves heat transfer, and the friction factor is influenced by the presence and location of triangular obstacles.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2023)
Article
Chemistry, Multidisciplinary
Kamsing Nonlaopon, Naveed Ahmad Khan, Muhammad Sulaiman, Fahad Sameer Alshammari, Ghaylen Laouini
Summary: This paper investigates the heat transfer of two-phase nanofluid flow between horizontal plates in a rotating system with a magnetic field and external forces. An efficient stochastic technique based on feed-forward neural networks with a back-propagated Levenberg-Marquardt algorithm is developed to examine the effect of variations in various parameters on the nanofluid properties.
Article
Thermodynamics
Ravikiran Balaga, Ramji Koona, Subrahmanyam Tunuguntla
Summary: The impact of various variables on thermal conductivity and rheological behavior, such as nanoparticle weight concentration and temperature, as well as the cumulative effects of wire coil insert and twisted tape on heat transfer coefficient and friction factor characteristics, is explored. The findings show that higher content of nanoparticles increases heat transfer as well as pressure drop.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
M. Basit Shafiq, Usman Allauddin, Mumtaz A. Qaisrani, Tauseef-ur-Rehman, Naveed Ahmed, M. Usman Mushtaq, Hafiz Muhammad Ali
Summary: This study investigated the improvement in thermal performance of heat exchangers through the combination of two passive techniques, nanofluids and coiled tubes. Numerical simulations showed that using nanofluids can increase the Nusselt number, especially in shell and helical coil tube heat exchangers.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Green & Sustainable Science & Technology
Amir Zolghadri, Heydar Maddah, Mohammad Hossein Ahmadi, Mohsen Sharifpur
Summary: This study utilized an artificial perceptron neural network model to predict the Nusselt number and energy consumption in the processing of tomato paste, showing reasonable agreement with experimental data. The model demonstrated successful prediction with a topology of 3-22-2, achieving desirable results in terms of correlation coefficient and mean square error.
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
Environmental Sciences
V. Tangestani, A. H. Meghdadi Isfahani
INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2020)
Article
Thermodynamics
Behnam Rajabzadeh, Mohammad Hojaji, Arash Karimipour
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2019)
Article
Thermodynamics
Kamal Ghani Dehkordi, Arash Karimipour, Masoud Afrand, Davood Toghraie, Amir Homayoon Meghdadi Isfahani
INTERNATIONAL JOURNAL OF THERMOPHYSICS
(2020)
Article
Thermodynamics
Mohammadreza Niknejadi, Masoud Afrand, Arash Karimipour, Amin Shahsavar, Amir Homayoon Meghdadi Isfahani
Summary: Experimental research showed that the combined use of a twisted tube and a rotating magnetic field enhances the overall thermohydraulic features of water-magnetite nanofluid. The best overall thermohydraulic features were observed in the case of nanoadditive concentration at 2%, Reynolds number at 500, and twist pitch at 10 mm, with a rotating magnetic field resulting from clockwise rotation of the first magnet and counterclockwise rotation of the second magnet.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Chemistry, Physical
Kamal Ghani Dehkordi, Arash Karimipour, Masoud Afrand, Davood Toghraie, Amir Homayoon Meghdadi Isfahani
Summary: This study aimed to investigate the effects of the electric field on the dynamical behavior of nanofluid in microchannels, revealing that enhancing the outer electric field results in quicker boiling phenomena in the nanofluid. The strength of the outer electric field is shown to be a critical factor influencing the atomic behavior of the nanofluid, leading to higher values of velocity, density, and temperature with increased external electric field strength.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Acoustics
Ali Hosseinian, Hamid Kolahdoozan, Amir Homayoon Meghdadi Isfahani
Summary: This study investigates the impact of different shroud plate structures and the use of open-cell metal foam layer on centrifugal fan noise. Experimental results show that using a curved shroud plate impeller and an OCMF layer on the cut-off surface can effectively reduce fan noise.
Article
Green & Sustainable Science & Technology
Mohammad Nouri, Amir Homayoon Meghdadi Isfahani, Alireza Shirneshan
Summary: The research found that adding Fe2O3 and Al2O3 nanoparticles to diesel fuel can improve combustion efficiency, performance, and emission characteristics of a diesel engine. Fe2O3 fuel blends showed better performance in increasing power, thermal efficiency, and reducing CO emissions. On the other hand, Al2O3 nanoparticle additives performed better in reducing BSFC, NOx, and SO2 emissions.
CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY
(2021)
Article
Thermodynamics
Hamidreza Azimy, Amir Homayoon Meghdadi Isfahani, Masoud Farahnakian
Summary: The study found that adding ultrasonic transducers to nanofluids can increase their stability and heat transfer coefficient, with the effect increasing with the concentration of nanofluid and decreasing with the flow rate.
HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Mechanical
F. Hosseini, A. H. Meghdadi Isfahani, M. Davazdah Emami, E. Mohseni
Summary: The aim of this study is to investigate the effect of excessive penetration of welding and natural gas impurity particles on increasing erosion in elbows and reducers. The results show that erosion rate increases with excessive penetration, particles size, particles flow rate, and natural gas flow rate. The effect of excessive penetration becomes more important in high-speed flows, and reducing it can significantly reduce erosion rate in elbows.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Thermodynamics
Hamidreza Azimy, Amir Homayoon Meghdadi Isfahani, Masoud Farahnakian, Arash Karimipour
Summary: This study demonstrates that installing an ultrasonic transducer on the walls of a heat exchanger can increase the heat transfer coefficient. The effectiveness of ultrasonic waves decreases with increasing flow rate.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Energy & Fuels
Mohammad Rasoul Omidvar, Amir Homayoon Meghdadi Isfahani, Ravinder Kumar, Akbar Mohammadidoust, Anand Bewoor
Summary: The study developed a multigeneration system using corn stalk biomass and solar energy for hydrogen and power production through hydrothermal gasification method. The system achieved high energy and exergy efficiencies, generating power, hydrogen gas, and clean water as products. Futhermore, the use of catalysts and combining biomasses with adding ammonia for desired productions is suggested for future research.
BIOMASS CONVERSION AND BIOREFINERY
(2021)
Article
Thermodynamics
Mehdi Hashemi Beni, Sobhan Emami, Amir Homayoon Meghdadi Isfahani, Alireza Shirneshan, Rasool Kalbasi
Summary: This paper investigates the modeling and control system of a saturated D-Type boiler under cold start conditions. The study includes the analysis of drum pressure, fuel consumption, and exergy efficiency during the cold start-up process, considering the asymmetrical 3D modeling of the furnace and detailed modeling of circulation circuits.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Ali Rezaei Miandoab, Seyed Amin Bagherzadeh, Amir Homayoon Meghdadi Isfahani
Summary: The study demonstrates that twisted-tape inserts have a significant impact on heat transfer at high volume fractions and Re. Artificial Neural Network and Genetic Algorithm can be used to accurately estimate the optimal parameter combination.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Thermodynamics
Hamidreza Azimy, Noushin Azimy, Amir Homayoon Meghdadi Isfahani, Seyed Amin Bagherzadeh, Masoud Farahnakian
Summary: In this study, the influence of ultrasonic waves and temperature variations on the heat transfer coefficient (HTC) using CNT-water nanofluid was investigated experimentally and numerically. The results showed that applying ultrasonic waves at powers of 35-50 W improved the heat transfer coefficient. Increasing the nanofluid concentration and fluid temperature also enhanced the HTC. The Nusselt number increased by 540.23% with increasing fluid temperature, mass fraction, flow rate, and application of ultrasonic waves. Furthermore, an Artificial Neural Network (ANN) was used to evaluate the HTC and Nusselt number, and the results were consistent with the experiments.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Thermodynamics
Siamak Karimi, Mohammad Mahdi Heyhat, Amir Homayoon Meghdadi Isfahan, Ali Hosseinian
HEAT AND MASS TRANSFER
(2020)
