Article
Thermodynamics
Ying Xi, Zhikang Yu, Lin Zhang, Aimei Yu, Lei Liu, Bingguo Bao, Youchang Zhao, Chengman Zhou, Bingjie Wu, Kexin Dong
Summary: This study develops a new type of straight wave packing to improve the heat and mass transfer characteristics of counterflow wet cooling towers. Experimental and numerical simulations investigate the effects of inlet air velocity, water drenching density, gas-liquid ratio, and packing height on the cooling tower's heat and mass transfer characteristics. Results show that compared to conventional straight wave packing, the novel packing increased cooling efficiency by 14.4%, providing a new approach for engineering practice. Analysis of the tower's operating conditions suggests that taller packing heights make it easier to meet cooling requirements, and smaller gas-liquid ratios and required air volumes can save up to 30% of the maximum air volume.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Zhaoyang Cui, Qian Du, Jianmin Gao, Rushan Bie
Summary: A deep cooling tower was designed to efficiently recover waste heat and gaseous water from humid flue gas. The design of tower equipment and absorption heat pump system was optimized. The running resistance of the tower is less than 240 Pa, and the structured packing achieves maximum heat transfer power under different liquid to gas ratios. The absorption heat pump system has a coefficient of performance of 1.71, and can achieve significant energy and water recovery, as well as reduce emissions of CO2, dust, SO2, and NOx.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
M. Muneeshwaran, Chi-Chuan Wang
Summary: The study aims to reduce the airside pressure drop of rectangular plain heat exchangers using superhydrophobic coating, which can lead to significant increases in heat transfer efficiency with higher inlet air temperatures and relative humidities.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Construction & Building Technology
Sampath Suranjan Salins, Shiva Kumar, Ana Tejero Gonzalez, Sawan Shetty
Summary: This study focuses on the design and construction of a forced draft counter flow cooling tower unit using different packing materials. The performance parameters of the cooling tower are determined through experiments, and it is found that the type of packing material significantly affects the tower's efficiency. Among the different packing materials, Celdek 7090 shows the best performance and energy efficiency.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Thermodynamics
Xiaohui Zhou, Weijia Wang, Lei Chen, Lijun Yang, Xiaoze Du
Summary: A novel water distribution mode is proposed for natural draft wet cooling tower, which divides the water distribution area into four subdomains with different diameters of sprayed water droplets to enhance cooling performance. The new water distribution mode increases air velocity in the central area and improves thermal performance in the external area.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
J. H. Yu, Z. G. Qu, J. F. Zhang, S. J. Hu, J. Guan
Summary: A new coupling model considering the interaction among spray zone, rain zone, and packing was proposed for investigating the thermal performance of counter-flow wet cooling towers. Experimental results showed a significant reduction in relative error when the spray zone and rain zone were coupled with packing, and the efficiency and exit water temperature of the cooling tower were affected by various factors.
Article
Thermodynamics
Jiamei Fang, Xuhui Zhao, Lin Zhang, Shi Bu, Zhikang Yu, Weigang Xu, Yiyang Hu, Yanfei Shan, Yong Li
Summary: A new heat transfer strategy to improve the thermal performance of closed wet cooling towers (CWCT) is proposed and validated through theoretical and experimental research. The influence of fan frequency, spray density, and processing water flow on the thermal performance of CWCT is studied, and an empirical formula for heat transfer coefficient is obtained.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2022)
Article
Thermodynamics
Cuilin Zhao, Mingwei Wang, Qi Gao, Shen Cheng, Suoying He, Jifang Zhao, Jianwei Zhan, Zhilan Liu, Zhe Geng, Shuzhen Zhang, Jianhui Qi, Ming Gao, Yuetao Shi
Summary: To address the poor cooling performance of mechanical draft dry cooling towers (MDDCT) in high ambient temperatures, this study proposes a dry-wet hybrid cooling technology that utilizes wet media to evaporatively cool the inlet air of the MDDCT. A MATLAB program is developed to investigate the effects of different variables on the cooling performance of the dry-wet hybrid cooling tower and its control strategy. The results demonstrate that the dry-wet hybrid cooling tower outperforms the MDDCT in high ambient temperatures, and the cooling performance can be significantly improved by adjusting the medium type, thickness, ambient temperature, humidity, and fan speed.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Rui Zhao, Shi Bu, Xuhui Zhao, Lin Zhang, Weigang Xu, Zhikang Yu, Jiamei Fang, Yixiang Ji, Yiyang Hu, Bingguo Bao
Summary: The closed wet cooling tower exchanges heat by direct contact between the air in the tower and the process water. A new elliptical finned tube is proposed to improve thermal performance, with a mathematical model established to study heat and mass exchange. The impact of wind velocity and spray density on cooling tower thermal performance is analyzed.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Jihad Salah Khan, Iftikhar Ahmad, Usman Khan Jadoon, Abdul Samad, Husnain Saghir, Manabu Kano, Hakan Caliskan
Summary: This study proposes a gray-box modeling approach for predicting the optimum mass flow rates of inlet streams in a Plate and Fin Heat Exchanger under uncertainty. By integrating genetic algorithm with a first principle model and replacing it with an artificial neural networks model, a novel gray-box framework is developed, which exhibits better effectiveness and higher outlet temperature than the direct application of the first principle model. The performance of this gray-box model is comparable to the integrated framework of genetic algorithm and first principle model, but with significantly reduced computation time, enhancing the heat exchanger's energy recovery and robustness to cope with uncertainty.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Weipeng Deng, Fengzhong Sun, Kun Chen, Xiaoyu Zhang
Summary: Under crosswind conditions, the airflow distribution of the mechanical draft wet cooling tower group becomes uneven, leading to reduced cooling capacity of leeward towers. A new retrofit method is proposed to improve the cooling capacity by removing the tower wall between the rain zone of the tower group. Numerical calculation and analysis show that the retrofit tower group can achieve a more uniform distribution of outlet water temperature and increase the circulating water temperature drop of the leeward tower under certain crosswind angles.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Energy & Fuels
Hasan Alimoradi, Madjid Soltani, Pooriya Shahali, Farshad Moradi Kashkooli, Razieh Larizadeh, Kaamran Raahemifar, Mohammad Adibi, Behzad Ghasemi
Summary: This study developed a numerical and empirical scheme to enhance the performance of cooling towers by combining the PSO algorithm with a neural network. Experimental analysis showed significant effects of packing compaction on performance. Results indicated that increasing air flow rate, water flow rate, and packing compaction can improve cooling tower efficiency.
Article
Thermodynamics
Weipeng Deng, Fengzhong Sun, Kun Chen, Xiaoyu Zhang
Summary: This study establishes a 3D model of the hybrid mechanical draft wet cooling tower (hybrid MCT) and explores its operation mechanism. The plume, water saving, and cooling capacity of the hybrid MCT are discussed. Results show that the ambient dry bulb temperature and circulating water temperature have a significant impact, while the relative humidity and circulating water flow rate have a relatively small impact. By adjusting the circulating water flow rate ratio and airflow resistance in the dry part, the water saving rate and cooling capacity of the hybrid MCT can be enhanced.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Xuehong Chen, Fengzhong Sun, Youliang Chen, Wei Yuan
Summary: This paper investigates the effects of air channels in wet cooling towers through a thermal-state model experiment. The results show that air channels can enhance heat transfer and ventilation performance, with P4 and P5 patterns being more effective. The P3 pattern is recommended for engineering applications.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2021)
Article
Thermodynamics
Nicolas Jourdan, Mohamed Kanniche, Thibaut Neveux, Olivier Potier
Summary: This study aims to investigate the hydrodynamic behavior of air-water counter flows in wet cooling towers using Computational Fluid Dynamics (CFD) simulations. The simulations successfully reproduced water falling films on the packing surface and allowed the calculation of local and system parameters. The results showed trends of increasing liquid film thicknesses and wetting rates with increasing water flowrate in agreement with experimental observations. A correlation of the interfacial area as a function of hydrodynamic adimensional numbers was proposed to characterize transfer phenomena in the packing.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2023)
Article
Engineering, Mechanical
Masoud Rashidi, Ahmad Sedaghat, Biltayib Misbah, Mohammad Sabati, Koshy Vaidyan
Summary: In this study, a high-speed Taylor-Couette system was developed for investigating drilling fluids at different rotational speeds, showing significant power saving with Al2O3 nanofluids at low volume concentrations. Results suggest that Bingham and HBE models are the best fit for Al2O3 nanofluids data.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Energy & Fuels
Ahmad Sedaghat, Mohammad Sabati, Fadi Alkhatib, Seyed Amir Abbas Oloomi, Farhad Sabri, Hayder Salem, Waqar Jan Zafar, Mahdi Ashtian Malayer
Summary: This research aims to use window film to regulate indoor temperature and humidity in office buildings to mitigate the impact of climate change. By collecting data and building models, it was found that offices with window films have increased indoor humidity and reduced temperature, leading to a significant decrease in cooling loads. Simulation results show the energy saved and reduced CO2 footprints by applying solar window films in buildings.
Article
Engineering, Petroleum
Masoud Rashidi, Ahmad Sedaghat, Biltayib Misbah, Mohammad Sabati, Koshy Vaidyan
Summary: This paper explores the behavior of non-Newtonian fluid flow with SiO2 nanoparticles in water-based mud through a high-speed Taylor-Couette system. By optimizing rheology models to fit experimental data, it is found that SiO2 WBM nanofluids can achieve energy savings and enhanced rheology at lower volume concentrations. The deviation of the Darcy friction factor from laminar to turbulent flow at a generalized Reynolds number beyond 2,000 serves as a good indicator for the flow condition of complex non-Newtonian nanofluids in real-life applications.
Article
Energy & Fuels
Ahmad Sedaghat, Seyed Amir Abbas Oloomi, Mahdi Ashtian Malayer, Fadi Alkhatib, Farhad Sabri, Mohammad Sabati, Hayder Salem, Waqar Jan Zafar, Ali Mostafaeipour, Alibek Issakhov, Mehdi Jahangiri, Kuaanan Techato, Shahariar Chowdhury
Summary: Research shows that in hot-arid climates, the use of window films can significantly reduce energy consumption in office buildings and decrease carbon footprint.
FRONTIERS IN ENERGY RESEARCH
(2021)
Article
Engineering, Biomedical
Mehdi Rahmati, Xiaolin Chen
Summary: Circulating Tumor Cells (CTCs) are important in early cancer detection and the dielectrophoretic DLD technique can effectively separate CTCs by utilizing cell size and dielectric properties. This technique operates at high flow rates and continuous separation is achieved by applying a field frequency close to the crossover frequency of CTCs.
BIOMEDICAL MICRODEVICES
(2021)
Article
Chemistry, Applied
Behzad Zakani, Sohrab Entezami, Dana Grecov, Hayder Salem, Ahmad Sedaghat
Summary: In this study, the effect of ultrasonic treatment on the lubrication performance of CNC aqueous suspensions was systematically investigated. The results showed that ultrasonication can significantly reduce the friction coefficient and wear of the lubricant.
CARBOHYDRATE POLYMERS
(2022)
Article
Materials Science, Paper & Wood
Behzad Zakani, Hayder Salem, Sohrab Entezami, Ahmad Sedaghat, Dana Grecov
Summary: Industrial lubricants improve machinery performance by reducing wear and friction between mechanical components. Developing eco-friendly lubricants is crucial for environmental protection. This study investigates the effect of nanoparticle concentration on the lubrication performance of cellulose nanocrystal (CNC) aqueous suspensions, and finds an optimum concentration range under mixed lubrication mode.
Article
Energy & Fuels
Biltayib Misbah, Ahmad Sedaghat, Masoud Rashidi, Mohammad Sabati, Koshy Vaidyan, Naser Ali, Mohamed Abdulsalam Ali Omar, Seyyed Shahabaddin Hosseini Dehshiri
Summary: In the drilling industry, the use of enhanced water-based mud with nanoparticles has the potential to significantly reduce energy consumption. This study compared the effects of Al2O3, SiO2, and TiO2 nanoparticles on the viscosity and friction factor of drilling fluids. The results showed that the addition of nanoparticles reduced shear stress, apparent viscosity, and friction factor, particularly at lower volume fractions and rotational speeds.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Multidisciplinary Sciences
Rashid Alavi, Arian Aghilinejad, Heng Wei, Soha Niroumandi, Seth Wieman, Niema M. Pahlevan
Summary: This study introduces a physiologically accurate in-vitro hydraulic setup that models the hemodynamics of the coupled atrioventricular-aortic system. The setup allows for two-way hemodynamic couplings and demonstrates a remarkable correspondence to clinical hemodynamics. The study also investigates the physiological relevancies of major global parameters in the circulatory system.
Article
Multidisciplinary Sciences
Rashid Alavi, Qian Wang, Hossein Gorji, Niema M. Pahlevan
Summary: Analysis of cardiovascular waveforms provides valuable clinical information. The intrinsic frequency (IF) method extracts physiologically relevant information about the cardiovascular system. This study proposes a machine learning-based method for determining IF parameters from a single carotid waveform. The method shows strong correlations with the standard L2 optimization-based method, regardless of measurement apparatus and device sampling rate.
Article
Construction & Building Technology
Ahmad Sedaghat, Hayder Salem, Wisam K. Hussam, Arash Mahdizadeh, Mohamad Iyad Al-Khiami, Mahdi Ashtian Malayer, Sayed M. Soleimani, Mohammad Sabati, Ramadas Narayanan, Mohammad Rasul, M. Masud K. Khan
Summary: Creating low-energy buildings in arid, hot desert climates like Kuwait is challenging. This research investigates the use of Bio-PCMs and cool roof coatings as energy-saving methods. The study analyzes thermal properties of two identical cabins under different cooling conditions and develops a model to study Bio-PCM integrated walls. Results show that autoclaved aerated concrete block walls perform best in desert and subtropical climates, while energy savings from cool roof methods are negligible. Incorporating insulation materials via sandwich panels enhances energy efficiency in some climates but increases energy consumption in others. This study provides insights into optimal wall materials and energy-saving strategies for hot climates.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Energy & Fuels
Biltayib Misbah, Ahmad Sedaghat, Saad Balhasan, Rida Elgaddafi, Mahdi Ashtian Malayer, Rana N. Malhas, Mohammed Omar, Manal Benomran
Summary: This study aimed to investigate the effect of temperature on the stability of commonly used polymers in water-based mud drilling operations. The addition of potassium chloride had a positive impact on the thermal stability of the drilling fluid. Polymer A exhibited superior performance at different temperatures, while Polymer B performed well at 200°F. Polymer C showed good filtration control and cake analysis performance at all temperatures.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Proceedings Paper
Green & Sustainable Science & Technology
Hayder Salem, Ahmad Sedaghat, Mahdi Ashtian Malayer
Summary: Cooling load demands have increased rapidly in recent years. Buildings in extreme hot climates consume more than 90% of the total electricity, but passive cooling techniques like the cool roof approach can improve thermal comfort. Two identical cabins were built in Kuwait to test different cool roof techniques, with one proposing the use of aluminum sheet tiles equipped with tilted fins to reduce roof temperature. Initial data showed similar thermal properties in both units, and the study will continue to explore improvements such as reflective paint or spacers between tiles and roof.
2023 7TH INTERNATIONAL CONFERENCE ON GREEN ENERGY AND APPLICATIONS, ICGEA
(2023)
Article
Geochemistry & Geophysics
Masoud Rashidi, Ahmad Sedaghat, Biltayib Misbah, Mohammad Sabati, Koshy Vaidyan, Ali Mostafaeipour, Seyyed Shahabaddin Hosseini Dehshiri, Khalid Almutairi, Alibek Issakhov
Summary: The study investigated the viscosity characteristics of an API standard drilling fluid under different flow conditions, finding that several rheology models matched well with the measured data.
Article
Thermodynamics
Mamdouh El Haj Assad, Han Bani Hani, Israa Al-Sawafta, Ahmad Sedaghat, Mohammad Alshabi, Shek Rahman
Summary: This paper analyzes the temperature distribution within a water jacket and a fiber laser end pumped by a top hat beam, finding that the temperature distribution strongly depends on the Brinkman number. The results are presented in dimensionless form for application to various end-pumped laser rods and fluid types.
Review
Thermodynamics
Shuling Guo, Ankuo Zhang
Summary: Low-temperature biopreservation is commonly used for medication storage to prolong their shelf life. However, cryo-injury can occur during cryopreservation, making it crucial to find a way to achieve long-term biopreservation without causing harm. The optimal storage temperature for different biomaterials should be investigated to improve storage efficiency. This review discusses the mechanisms of cryo-injury and biopreservation, as well as the reasons for storing biological tissues at various temperature zones. It provides valuable insights for the development of biostorage technology.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
M. Mohsin Tanveer, Craig R. Bradshaw, Joe Orosz, Greg Kemp
Summary: This study investigates the optimal geometric parameters for a spool compressor using simulation models, and the results indicate that a eccentricity ratio of 0.75 and L/D ratios between 1-1.5 can maximize the volumetric and isentropic efficiencies.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Kongkuai Ying, Zhenhua Jiang, Wenting Wu, Jinjian Chu, Shaoshuai Liu, Yinong Wu
Summary: The Stirling/pulse tube cryocooler (SPC) is a highly efficient and long-lasting cryocooler for space applications. It has the ability to adjust the inter-stage refrigeration capacity dynamically by controlling the Stirling displacer in the first stage. This paper proposes an SPC with a second-stage active phase shifter (APS) that can control the phase difference at the second-stage hot end in real time. The experimental results show that the SPC with the APS can provide refrigeration capacity at different temperatures, with a minimum temperature of 13.5K.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Ligeng Li, Hua Tian, Kai Liu, Yibo Wu, Xuan Wang, Xingyu Liang, Gequn Shu
Summary: This study focuses on improving the performance of carbon dioxide refrigeration systems by introducing a multi-ejector design with three controllable ejectors. Experimental analysis shows that the system's performance can be significantly improved by adopting an optimum pressure control strategy under different operating conditions.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Joseph Al Khoury, Rabih Al Haddad, Ghiwa Shakrina, Christelle Bou Malham, Haytham Sayah, Chakib Bouallou, Maroun Nemer
Summary: This study investigates two implementation methods for calculating refrigerant thermodynamic properties and compares their performance. The results show that the implicit fitting method significantly speeds up simulation time and offers greater flexibility for modeling complex energy systems.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Mariella Mateo-Villanueva, Rodolfo Echarri
Summary: This article details three models of different complexity levels for predicting the cold production of a solar cooling device and compares their advantages and disadvantages. The results show that the transient model underestimates the cold generation, while the equilibrium model and universal model overestimate it. The transient model is a useful tool for analyzing the impact of different variables in a solar adsorption refrigeration system, while the simpler models can be used for preliminary design and feasibility studies.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Amin M. Elsafi, Majid Bahrami
Summary: The novel spherical micro-absorbers offer high sorption capacity and surface-to-volume ratios, solving issues such as solution carryover and corrosion associated with conventional absorbers.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
