Article
Thermodynamics
Anatoliy Khait, Vincenzo Bianco, Alexander Lovtsov, Alexander Noskov, Vladimir Alekhin
Summary: The formation of vortex flow in the Ranque-Hilsch vortex tube was studied, and a novel transonic nozzle design was proposed to accelerate the vortex flow to supersonic speeds. Improper selection of nozzle dimensions may lead to destabilization of the vortex flow, but correction using a simplified model can stabilize the flow and improve energy efficiency. The novel transonic nozzle extends the region occupied by the supersonic vortex, leading to increased temperature separation effect in the energy separation chamber.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
M. Mirjalili, K. Ghorbanian
Summary: A 2D numerical investigation was carried out on the transient thermo-fluid processes in a vortex tube with a cold mass fraction of 0.44, revealing that the tangential velocity is the most significant velocity component and dominates the heat transfer and energy conversion processes. Additionally, the core of the tube experiences the highest pressure gradient and almost zero tangential and radial velocities.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2021)
Article
Thermodynamics
Raphael Oberti, Junior Lagrandeur, Sebastien Poncet
Summary: A numerical benchmark is conducted to evaluate the performance of a Ranque-Hilsch vortex tube using subcritical carbon dioxide as the working fluid. Different thermodynamic and turbulence models are compared to experimental data, and the k-? SST model demonstrates superior performance in terms of cold and hot outlet total temperature predictions. The accuracy is further improved by considering real-gas equations of state, particularly with the multi-parameter Span-Wagner equation at high operating pressure. The study examines internal flow features and discusses the validity of common assumptions made in one-dimensional thermodynamic models, and quantifies the exergy efficiency of the vortex tube at various cold mass fractions.
Article
Thermodynamics
Xiangji Guo, Bo Liu, Bo Zhang, Yong Shan
Summary: The study focused on analyzing the precessing frequency characteristics in a vortex tube to investigate the energy separation process, with findings showing that an increase in inlet pressure can improve performance and significantly increase the peak frequency. Moreover, as the precessing frequency grows in the vortex tube, a higher energy transfer capability is observed, resulting in improved performance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Energy & Fuels
Harun Gokce
Summary: The study reviewed the performance of parallel RHVTs using oxygen gas with different inlet pressures, nozzle materials, and orifice numbers. The results were modeled using multiple linear regression and optimized using Taguchi L16 mix type orthogonal sequence. The effectiveness of the optimization was confirmed through confirmation tests, showing its applicability in evaluating RHVT performances.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2021)
Review
Engineering, Chemical
Pradeep Ambedkar, Tanmay Dutta
Summary: This paper reviews previous studies on the Ranque-Hilsch vortex tube (RHVT) to analyze its mechanism and influencing parameters for energy, phases, and species separation. The effect of different parameters such as nozzle number and geometry, L/D ratio and divergent angle of the main tube, and conical valve geometry are discussed. The study also explores the impact of inlet pressure, temperature, and thermo-physical properties of working fluids on the efficient operation of RHVT. The broad applications of RHVT in mechanical processes, trans-critical refrigeration systems, water droplet separation, and liquid oxygen collection systems are discussed.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Thermodynamics
Mark J. Parker, Anthony G. Straatman
Summary: An experimental investigation on the Ranque-Hilsch vortex tube was conducted to study the effects of pressure magnitude, pressure drop, and pressure ratio on temperature drop. The study found that the temperature drop is best correlated to the ratio of the inlet and cold outlet pressures, suggesting a polytropic process.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Xiangji Guo, Bo Zhang, Yong Shan
Summary: In this study, a large eddy simulation model (LES) was used to analyze large-scale precessing vortices and energy separation in a Ranque-Hilsch vortex tube. It was found that the tube contains vortex structures of secondary circulation flow and precessing vortices, which can drive part of the reverse flow towards the main flow by overcoming adverse radial pressure gradients. Through processes such as vortex shedding, energy transfer was achieved from the inner layer to the outer layer in a heat pump cycle driven by vortex core precession.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Guoxiang Tang, Fachun Liang, Zhengyu Wang, Ting Yang, Qinggang Zeng, Zheheng Ma, Jiaxin Wang
Summary: The energy separation characteristics of a vortex tube installed with a flow straightener were experimentally investigated. A combined method of energy and exergy analysis was used to systematically evaluate the vortex tube with a straightener, and the temperature separation process facilitated by the flow straightener was analyzed in depth. The effects of various factors on cold and hot temperature differences, coefficient of performance, exergy efficiency, and internal temperature field were experimentally investigated. The results showed that the presence of a hole in the center of the flow straightener weakened the energy separation performance of the vortex tube, and a flow straightener with 4 blades, 0 diameter ratio, 60 degrees blade angle, and 0.65 installation position produced optimum energy separation performance and exergy efficiency.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Murat Korkmaz, Adil Binal, Huseyin Kaya, Volkan Kirmaci
Summary: An artificial neural network-based ternary diagram was used to predict temperature separation in a counter-flow Ranque-Hilsch vortex tube. The working fluid and nozzle materials were chosen as effect parameters, and the temperature difference between the hot and cold outlets was used as the performance indicator. Different algorithms combinations were attempted to obtain the best estimates, and new equations were developed based on the values measured in the experimental set to estimate the temperature difference in the vortex tube. Additionally, a ternary diagram was developed to evaluate the temperature differences using experimental conditions for oxygen gas and air.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Thermodynamics
O. V. Vitovsky
Summary: This paper discusses the process of energy separation in a vortex tube using a screw-type vortex generator, which had not been used for this purpose before. The study found that increasing inlet pressure enhances temperature separation while an increase in outlet pressure reduces the effect. Experimental results showed the temperature separation in the swirling gas flow generated by the screw vortex generator.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2021)
Article
Thermodynamics
Xiangji Guo, Leilei Cao, Bo Zhang, Nian Li, Fengyi Tang
Summary: This study analyzes the flow field and energy separation of a vortex tube with five different area ratios through experiments and numerical simulation. The results show that different area ratios lead to different flow structures and thermal behaviors. A performance evaluation index is proposed to improve the optimization of vortex tubes.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
A. Karthik, Vighnesha Nayak
Summary: A vortex tube is a simple device without moving parts that separates a high pressure inlet stream into two low pressure outlet streams, one with higher temperature and one with lower temperature. Various theories have been proposed to explain the mechanism of temperature separation in the vortex tube, with this article focusing on analyzing the heat transfer between the core and peripheral streams. The study establishes an empirical relationship between the length of the vortex tube and the surface that divides the hot and cold flows, as well as evaluates the dependence of heat transfer on the length of the vortex tube while keeping the diameter constant.
NUMERICAL HEAT TRANSFER PART B-FUNDAMENTALS
(2021)
Article
Thermodynamics
Nolan J. Dyck, Mark J. Parker, Anthony G. Straatman
Summary: This work investigates the impacts of different boundary conditions on the temperature separation predictions of 3D Computational Fluid Dynamics (CFD) models of the RHVT. The inclusion of exit plenums and inlet shroud in the computational models is also examined. The study shows that reasonable predictions can be obtained by imposing the inlet mass flow combined with mass flow rate at one outlet and pressure at the other, while errors in inlet flow or mass flow split can occur with multiple pressure conditions at RHVT boundaries. Additionally, each turbulence model predicts a unique eddy viscosity distribution and the length of the stagnation stream surface is negatively correlated to the eddy viscosity. The integral results alone are not sufficient to determine the best turbulence model.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2022)
Article
Thermodynamics
He Peng, Guo Xiangji
Summary: The development of the Ranque-Hilsch vortex tube has been stagnant since the 1950s, and its performance has remained constant for 70 years. The lack of a mature design method and unclear flow structure and energy separation mechanism have limited its widespread industrial adoption. This study investigates the relationship between cooling performance and the area ratio of a vortex tube and suggests that the inlet mass flowrate per unit area can be a geometric performance benchmark.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Thermodynamics
Sergio Croquer, Olivier Lamberts, Sebastien Poncet, Stephane Moreau, Yann Bartosiewicz
Summary: This study investigates the flow topology in the mixing chamber of a supersonic ejector using Large Eddy Simulation (LES). The results show that the mixing layer transitions from laminar to turbulent and vortices are identified in the first quarter of the mixing chamber. The study also reveals the occurrence of shock train towards the end of the mixing chamber, enhancing mixing.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Antoine Metsue, Romain Debroeyer, Sebastien Poncet, Yann Bartosiewicz
Summary: Thermodynamic models are essential for designing supersonic ejectors, but current models struggle to fully integrate the physics within the device, with the compound-choking theory potentially better suited for predicting the behavior of double choked ejectors.
Article
Thermodynamics
Mohamad Cheayb, Mylene Marin Gallego, Mohand Tazerout, Sebastien Poncet
Summary: The study focuses on the economic aspect of T-CAES by coupling an economic model to the thermodynamic model to investigate and optimize design parameters, analyzing and discussing plant costs and economic benefits compared to electrochemical batteries. The optimal range of storage pressure and the impact of power scale on unit cost are key factors affecting the economic competitiveness of T-CAES.
Article
Energy & Fuels
Farhad Afsharpanah, Khashayar Pakzad, Seyed Soheil Mousavi Ajarostaghi, Sebastien Poncet, Kurosh Sedighi
Summary: Frequent power outages in developing countries lead to food spoilage, where ice storage systems can serve as backup cooling sources. Geometrical optimization of parameters such as helical pitch length can significantly improve the charging rate of ice storage units. The modified Stefan number of refrigerant flow has a considerable impact on the charging rate, while natural convection does not have a noticeable effect on ice formation.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Thermodynamics
Jihyuk Jeong, Alla Eddine Benchikh Le Hocine, Sergio Croquer, Sebastien Poncet, Benoit Michel, Jocelyn Bonjour
Summary: The present work presents a numerical simulation of heat transfer inside a refrigerated truck trailer equipped with eutectic plates. The results indicate that during the door opening period, placing the eutectic plates on the roof of the trailer leads to lower average temperatures inside the trailer compared to placing them on the back. However, the presence of cargo eliminates the formation of specific zones and limits the infiltration of outside air.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Amir Momeni Dolatabadi, Jamshid Moslehi, Mohsen Saffari Pour, Seyed Soheil Mousavi Ajarostaghi, Sebastien Poncet, Muslum Arici
Summary: The study aims to reduce condensing losses of wet steam flow and increase the energy efficiency of steam turbine by injecting Nano-droplets in nucleation zone. The results are validated with experimental data and the SST k-u turbulence model is utilized to simulate the effects of Nano-droplets. Effective energy parameters have been presented, resulting in a significant decrease in condensation losses and improvements in efficient energy and Mach number.
Article
Thermodynamics
Raphael Oberti, Junior Lagrandeur, Sebastien Poncet
Summary: A numerical benchmark is conducted to evaluate the performance of a Ranque-Hilsch vortex tube using subcritical carbon dioxide as the working fluid. Different thermodynamic and turbulence models are compared to experimental data, and the k-? SST model demonstrates superior performance in terms of cold and hot outlet total temperature predictions. The accuracy is further improved by considering real-gas equations of state, particularly with the multi-parameter Span-Wagner equation at high operating pressure. The study examines internal flow features and discusses the validity of common assumptions made in one-dimensional thermodynamic models, and quantifies the exergy efficiency of the vortex tube at various cold mass fractions.
Article
Thermodynamics
V. Tamimi, M. J. Esfehani, M. Zeinoddini, M. S. Seif, S. Poncet
Summary: The unbounded linearly increasing responses in galloping instability make sharp-edge oscillators a beneficial solution for bladeless energy harvesting. While the performance of single square oscillators has been the subject of several studies in the past, there is still little knowledge about their hydrokinetic energy performance in tandem configurations. The synergy of tandem configuration at close spacing improves the maximum efficiency of the energy harvester by 97% as compared to two separate isolated oscillators.
Article
Thermodynamics
Ahmed Mansour, Raphael Oberti, Hakim Nesreddine, Sebastien Poncet
Summary: A thermodynamic model is used to analyze a transcritical carbon dioxide heat pump cycle integrating a vortex tube. The objective is to prove that a vortex tube is beneficial in raising heat pump efficiency. The study found that the heating coefficient of performance of the vortex tube heat pump is improved by a maximum of 43.7% compared to that of the conventional heat pump when parameters such as hot exit pressure and desuperheater glycol mass flow rate are optimized.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Alla Eddine Benchikh Le Hocine, Sebastien Poncet, Hachimi Fellouah
Summary: In this study, a powerful double-intake and rotor squirrel cage fan was designed and optimized using open source libraries: Dakota, Salome and OpenFoam. By maximizing and minimizing the total efficiency and the force applied on the impeller, the performance of the fan was improved. A coupling was achieved between CFD, Latin Hypercube Sampling, Kriging metamodel and Efficient Global Optimization to find the optimal design. Configuration 2 improved the efficiency by 7.64% and reduced the force by 33.36% compared to Configuration 1. The Kriging and EGO models accurately predicted the objective functions of the optimal design with a maximum error of 4.50%. Based on the optimal design of Configuration 2, a blade trimming was applied, which improved the initial efficiency by 7.86%. The optimal prototype was successfully built and validated against experimental data with a maximum error of 1.10%.
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2023)
Article
Thermodynamics
Alexandre Coulombe, Mouna Rahal, Hachimi Fellouah, Sebastien Poncet
Summary: In this study, a 1D frost formation model is improved and validated using experimental data. It is found that larger plate spacing is less affected by frost growth, and the heat recovery efficiency decreases from 87% to 77% for a 2.5 mm spacing after 25 minutes.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Engineering, Marine
Sergio Croquer, Pilar Diaz-Carrasco, Vahid Tamimi, Sebastien Poncet, Jay Lacey, Ioan Nistor
Summary: Climate change and rising sea levels pose a challenge for predicting wave-coastal structure interactions due to their stochastic nature, coexistence of various phenomena, and wave transformations. This study presents a validated two-phase model to study wave dynamic interactions with impermeable structures, considering air compressibility and turbulence effects. The model is applied to analyze wave interactions with vertical walls in Saint-Lawrence Bay, Canada, using statistical data of wave conditions. Results provide insights into hydrodynamic loads and overtopping for different wave scenarios.
Article
Engineering, Multidisciplinary
Mahmoud A. Alzoubi, Oraib Al-Ketan, Jayaveera Muthusamy, Agus P. Sasmito, Sebastien Poncet
Summary: This paper introduces innovative T-shape micromixers equipped with various 3D printed Gyroid matrices aiming to boost the mixing performance. A numerical model has been derived and validated to investigate the impact of various Gyroid matrices on the mixing index, pressure drop, and performance index of T-shape micromixers at various Reynolds and Schmidt numbers. The results indicate that the twisted Gyroid matrix provides the highest enhancement in the mixing performance by boosting the mixing index up to 172% and shortening the mixing channel by 41%.
RESULTS IN ENGINEERING
(2023)
Article
Thermodynamics
Daryoush Dadpour, Mohammad Gholizadeh, Mohammad Estiri, Sebastien Poncet
Summary: Waste heat recovery systems are proposed as a promising solution to reduce energy consumption. This paper introduces a novel waste heat recovery system installed on a ship using supercritical/transcritical CO2 waste heat recovery, capable of generating power and cooling. The system is optimized to achieve high energy efficiency, exergy efficiency, and low capital cost, with a net power output of 9.061 kW and cooling output of 19.522 kW at design condition.