Thermofluid - Science topic

Bioelectronics, the merging of biology and electronics, can monitor and modulate biological behaviors across length and time scales with unprecedented capability. Current bioelectronics research largely focuses on devices' mechanical properties and electronic designs. However, the thermofluidic control is often overlooked, which is noteworthy given...

In High Pressure Aluminium Die Casting, poor mould cooling can have serious consequences. For instance, uneven heat distribution can cause mould stress and impair the material properties through part warping. Furthermore , efficient removal of excess heat means the part can be safely ejected from the mould quicker, minimising production cycle time....

An exploratory investigation was conducted to analyze a tubular heat exchanger's turbulent heat transfer characteristics using an innovative baffle plate design. The design incorporated a perforated conical baffle plate and an adjustable rectangular deflector. The strategic placement of this baffle plate at the heat exchanger inlet facilitated a sw...

Anticipating the swirl turbulent flow and heat transfer phenomena within a nozzle is tremendously challenging due to the complexities of measurement diagnostics. The amalgamation of nanoparticles with fluids often exacerbates this perplexity for the resurgence of effective fluid properties that ambiguously affect thermo-fluidic behaviors. This stud...

In this study, we present an immersed boundary method to analyze interactions between fluids and bodies in two-dimensional (2D) flows around complex geometries, focusing on heat transfer and turbulence. The method uses an Eulerian grid for the fluid, and another Lagrangian grid for the immersed body, ensuring conditions of no slip and considering h...

The paper provides a commentary on the theme of "Current and Future Trends in Tribo-logical Research: Fundamentals and Applications", which is a special feature issue commemorating the 10th anniversary of the journal, Lubricants. A historical discourse is provided regarding various aspects of tribology as a multidisciplinary subject that interacts...

Artificial intelligence (AI) is shifting the paradigm of two-phase heat transfer research. Recent innovations in AI and machine learning uniquely offer the potential for collecting new types of physically meaningful features that have not been addressed in the past, for making their insights available to other domains, and for solving for physical...

This research presents a comprehensive investigation into the flashing process within the evaporation zone of a multistage flashing (MSF) desalination chamber. It introduces a novel classification of the flashing process as ideal, finite, and infinite, aiming to advance the understanding of this critical phenomenon. A validated volume-of-fluid (VOF...

This study focuses on the aerodynamic optimization of the re-entry capsule (REC) Orion Crew Exploration Vehicle (CEV) module, evaluating its performance using computational fluid dynamics (CFD). Three different models, namely Baseline, 2-Duct, and 4-Duct, are investigated under a wide range of flow speeds, from supersonic (Ma=1.6) to hypersonic (Ma...

5th Generation District Heating and Cooling (5GDHC) provides a promising pathway for decarbonising the thermal sector. To quantify the synergies between heating, cooling, and electricity, complex thermofluid models are required. Modelica offers a potential solution for developing such models but despite recent research efforts, there is a lack of b...

The paper deals with the numerical simulation on polymer ablation phenomena during electric arc ignition process. The calculations from particle composition of high-temperature polymer vapor to the electromagnetic thermofluid simulation were consistently performed. In the present paper, first, methods and calculation results of the particle composi...

In this work, in the area of Computational Fluid Dynamics (CFD), more specifically in the area of thermofluid dynamics for two-dimensional flows (2D), and also considering, the fluid-body interaction, allied to the phenomena of heat-transfer by mixed convection and the beginning of processes of the turbulent flow phenomenon in the fluid-body intera...

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned outages. Accurately estimating the hot‐spot temperature (HST) of a power transformer is important for regulating the load and ensuring long‐term operation. In this study, a closed‐loop model of a 110‐kV product transformer with an oil na...

Decarbonization efforts in the United States has resulted in the increasing interest in flexible operation of nuclear power plants or thermal storage-based hybrid energy systems integrated with the power grid. Consequently, the need for rapid and effective modeling and simulation of such integrated systems is becoming critical. This requires modeli...

This study concerns the numerical simulation and the experimental implementation of a low-scale Phase Change Material-based (PCM-based) condenser, to be included in a PCM-based portable cooling systems. In this category of cooling systems, the PCM can be integrated either in the condenser or in the evaporator. In the present study, the PCM is integ...

A mathematical model is presented to analyze the double diffusive transport of hybrid nanofluids in microchannel. The hybrid nanofluids flow is driven by the cilia beating and electroosmosis in the presence of radiation effects and activation energy. Cu–CuO/blood hybrid nanofluids are considered for this analysis. Phase difference in the beatings o...

For future hypersonic and supersonic flight, clean, sustainable and energy-efficient propulsion should be addressed in the general background of the sensational clean electric transition of aircraft. This chapter is to draw the attention of the research communities on the possible feasibilities and challenges of hydrogen-electric propulsion in hype...

Understanding the nucleation and growth dynamics of the surface bubbles generated on a heated surface can benefit a wide range of modern technologies, such as the cooling systems of electronics, refrigeration cycles, nuclear reactors and metal industries, etc. Usually, these studies are conducted in the terrestrial environment. As space exploration...

In the EU, the Water-Cooled Lithium Lead (WCLL) Breeding Blanket (BB) concept is one of the candidates for the design of the DEMO reactor. From the past campaign of analysis emerged that the thermal-induced stress led to the failure in the verification of the RCC-MRx structural criteria. Hence, in this paper the classic conceptual design approach,...

To examine and investigate the impact of nanofluid on heat exchanger performance, including the total heat transfer, the effect of friction factor, the average Nusselt number, and the thermal efficiency, the output heat transfers of a shell and tube heat exchanger using ZnO nanoparticles suspended in water has been conducted numerically. The govern...

The market of electric storage systems is widely dominated by Lithium ion batteries, whose peculiarity is the need for a thermal management system, whose proper design is complicated by the interaction. among different design and operating parameters. A specific methodology for carrying out the task is still lacking. In this context, the present pa...

Physics-informed neural networks (PINNs) were developed to overcome the limitations associated with the acquisition of large training data sets that are commonly encountered when using purely data-driven machine learning methods. This paper proposes a PINN surrogate modeling methodology for steady-state integrated thermofluid systems modeling based...

It is well known that driving while fatigued is dangerous and can lead to serious traffic accidents. However, there is a lack of studies on the mechanism of fatigue. This paper sought to infer changes in the cardiovascular system through hand and head skin temperature peripheral factors via an integrated lumped parameter model. A multi-layer inner...

The paper deals with the numerical simulation on polymer ablation phenomena during electric arc ignition process. The calculations from paticle composition of high-temperature polymer vapor to the electromagnetic thermofluid simulation were consistently performed. In the present paper, first, methods and calculation results of the particle composit...

Supercritical carbon dioxide (sCO2) power cycles have been identified as an attractive technology to reduce capital and operating expenditure of concentrated solar power (CSP) plants. Numerous studies have investigated different layouts and operating parameters at the system-level in search of an optimal cycle configuration. Two cycle layouts provi...

Colloidal crystals are interesting as functional structures due to their emergent photonic properties like photonic stop bands and bandgaps that can be used to redirect light. They are commonly formed by a drying process that is assisted by capillary forces at the drying fronts. In this manuscript, we demonstrate the optically induced dynamic therm...

With the availability of Excel on most personal computers without additional cost, its powerful tools for data analysis and visualisation encouraged its use as an educational tool in various engineering subjects. With respect to thermofluid analyses, the lack of built-in functions for fluid properties in Excel motivated a number of academic institu...

Integrated whole-boiler process models are useful in the design of biomass and coal-fired boilers, and they can also be used to analyse different scenarios such as low load operation and alternate fuel firing. Whereas CFD models are typically applied to analyse the detail heat transfer phenomena in furnaces, analysis of the integrated whole-boiler...

A framework for topology optimization of conformal cooling channels is proposed, which paves the way towards automated design of additively-manufactured cooling channels, required in applications such as the efficient heat management of die casting molds. Combining a selection of pertinent techniques and methods, the proposed density-based approach...

Simulation programs modeling cyclic processes can be used in thermodynamics lectures to promote understanding. Modelica-based simulation environments are a good starting point for the developmentof such programs, but the handling of the corresponding thermo-fluid standard library is very difficult for non-experts. The recently presented DLR ThermoF...

Nanofluids are an emerging class of heat transfer fluids that are engineered by dispersing nanoparticles in conventional fluids. They represent a promising, multidisciplinary field that has evolved over the past two decades to provide enhanced thermal features, as well as manifold applications in thermal management, energy, transportation, MEMs and...

Nanofluids are an emerging class of heat transfer fluids that are engineered by dispersing nanoparticles in conventional fluids. They represent a promising, multidisciplinary field that has evolved over the past two decades to provide enhanced thermal features, as well as manifold applications in thermal management, energy, transportation, MEMs and...

Cardiovascular related illness development of a biomedical solution modelling both the right and left side of the arterial system. Both sides start from the left ventricle of the heart, through to the aorta and then branching off on both sides to end up in the carotid and radial arteries on the left and right side. modelling both sides as we had...

Wetting functionalities of rough surfaces are largely determined by the Laplace pressure generated across liquid–gas interfaces formed within surface structures. Typically, rough wetting surfaces create negative Laplace pressures, enabling capillary wicking, while rough non‐wetting surfaces create positive Laplace pressures, exhibiting fluid repell...

The paper presents an application of the semi‐analytical differential transform method (DTM) to thermofluidics of generalized Couette flow of couple stress fluid inside a composite channel. The channel comprises a fluid‐saturated porous layer and a clear fluid region. The flow is caused by a uniformly favorable pressure gradient applied at the mout...

The Geothermal Institute has been developing a tool for process design and optimisation of geothermal steam gathering systems by integrating a compilation of several geothermal practitioners' published theories and field experiences over the past eight decades. The tool aims to solve the typical challenges identified in geothermal steamfields world...

To elucidate the thermofluid reacting environment and thermal stress inside a solid oxide fuel cell (SOFC), a three-dimensional SOFC model is implemented by using the finite element method in the commercial software COMSOL Multiphysics®, which contains both a geometric model of the full-cell structure and a mathematical model. The mathematical mode...

This paper introduces the DLR Thermofluid Stream Library: a free open-source library for the robust modeling of complex thermofluid architectures. Designed to be easy to use, easy to adapt, and enriched by a number of examples, this library contains the fundamental components for many different applications, such as thermal management of electric c...

A novel and advanced analysis tool, based on the resolution of the inverse heat conduction problem, is used to evaluate wall-to-fluid heat fluxes in a metallic flat-plate pulsating heat pipe. The device under analysis is made of copper and formed by 16 channels having a squared section of 3 × 3 mm2 and filled with a water–ethanol mixture (20 wt.% o...

Novel detached curved ribs are proposed in this study and their influence on turbulent thermofluidic features in a two-pass U-shaped square channel is experimentally investigated using particle image velocimetry (PIV) and infrared thermography (IRT). Due to their geometric complexity, the ribs are fabricated with the 3D printing technology-fused de...

This book compiles selected articles from the 7th International Conference on Production, Energy and Reliability ICPER2020. the book is subdivided into several sections, including Thermofluids, Reliability, Materials, and manufacturing.

Nanofluids contains tiny particles in the working liquid due to which heat conduction is raised appreciably. Further, existence of the motile microorganisms boosts the thermal and mass transport in the system and so the improvement is developed in the stability of nanofluid. In this perspective, the emphasis of the existing analysis is to explore t...

In this review, the condensation HTCs (heat transfer coefficients) and pressure drop characteristics of some major low-global-warming-potential (GWP) refrigerants alternative to R-134a such as R-1234ze(E), R-1234ze(Z), R-1234yf, R-513A, and R-450A are reviewed. The thermofluids’ characteristics inside/outside a tube, minichannel, microfin tube, and...

Aeroengine performance is determined by temperature and pressure profiles along various axial stations within an engine. Given limited sensor measurements, we require a statistically principled approach for inferring these profiles. In this paper we detail a Bayesian methodology for interpolating the spatial temperature or pressure profile at axial...

Manuscript Number: IJTF-D-22-00241 A note on the Leveque’s solution to the Cartesian Graetz problem with free convection Marco Rosales Dear Dr Belhocine, Thank you for reviewing the above referenced manuscript. I greatly appreciate your contribution and time, which not only assisted me in reaching my decision, but also enables the author(s) to...

In this work, a numerical optimisation process is applied to improve the fluid dynamical aspect of an innovative direct liquid cooling strategy for lithium-ion–based HEV/EV. First, the thermofluidic numerical model of the battery cell defined by means of CFD computational tools was validated with experimental tests. Then, a comparison between diffe...

The use of supercritical carbon dioxide (sCO2) power cycles for concentrated solar power (CSP) applications is becoming increasingly attractive since these cycles may offer lower capital costs and increased thermal efficiency. However, there are currently no utility-scale sCO2-CSP tower plants in operation. Therefore, to aid in the design and analy...

In this study, the energy charging mechanism is mathematically modeled to determine the impact of design modifications on the thermofluidic behavior of a phase change material (PCM) filled in a triplex tube containment geometry. The surface area of the middle tube, where the PCM is placed, is supported by single or multi-internal frustum tubes in v...

Cell separation techniques based on dielectrophoresis are of high interest as an effective method of performing cell separation non-invasively on cells. However, dielectrophoresis devices have the problem that cells in the device are exposed to a high-temperature environment due to the generation of Joule heat caused by high-voltage application and...

This paper presents a concurrent topology optimization approach to design multi-scale fluid channels, inlets, and outlets for efficient cooling capabilities. An approximate but low-cost thermofluidic model is used to predict the temperature distributions, in which the Darcy model is utilized to simulate the fluid flow. A novel boundary-based penalt...

Among the measures that improve the combustion process and reduce emissions in the design of dual-fuel engines is the use of the RCCI combustion strategy. This paper attempts to investigate the effects of biodiesel and diesel fuels, fuel injection time, and fuel injection rate in the RCCI combustion mode. In this study, using CONVERGE CFD commercia...

We provide an ab initio scaling analysis for liquid film thickness and Nusselt number of a steady laminar jet impinging a rotating heated plate. We have probed the limiting scaling regimes by incorporating the evaporative effects at the liquid–vapor interface. The dependence of liquid film thickness and Nusselt number on Reynolds, Rossby, and Prand...

Advances in Information and Communications Technology (ICT) as well as the present challenges of COVID-19 have led to a new paradigm causing an absolute or partial transition from in-person classroom teaching-learning to online. There is little information available on research efforts that investigated the impact of an online learning approach on...

While numerical modelling of different types of nanofluids in various microchannel heat sink geometry under different flow conditions are many, few involved utilizations of experimental data. Reports so far have indicated the potential cooling capability of nanofluids in general, yet none have investigated the effects of the surfactant alone on the...

The research community agrees that the main indirect way the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads among people who do not keep social distance is through the emission of infected respiratory droplets. Infected people exhale droplets of different sizes and emission velocities while breathing, talking, sneezing, or cou...

Fluids containing colloidal suspensions of nanometer-sized particles (nanofluids) have been extensively investigated in recent decades with promising results. Driven by the increase in the thermal conductivity of these new thermofluids, this topic has been growing in order to improve the thermal capacity of a series of applications in the thermal a...

Boron nitride nanosheets (BNNS) were recently synthesized in a powder form using inductively coupled plasma through two readily-scalable bottom-up routes: (i) heterogeneous nucleation using amorphous boron particles and nitrogen, (ii) homogeneous nucleation from ammonia borane and nitrogen. The operating pressure was found to play a significant rol...

Among the techniques offered to improve the efficiency of heat exchangers, the Dimpled surfaces were repeatedly reported as an applicable solution. In this regard, the current study is formed to evaluate the thermofluidic performance of Dimpled-Protruded tubes while following four novel investigations. Firstly, the impact of Protrusions next to the...

Arbitrary shaping of temperature fields at the nanometer scale is an important goal in nanotechnology; this is challenging due to diffusive nature of heat transfer. In the present work, we have numerically demonstrated that spatial shaping of nanoscale temperature fields can be achieved by plasmonic heating of a single titanium nitride (TiN) nanost...

In 2020, Professor Adel Benchabane, the Publication Director of Alwaha Scientific Publishing Services (ASPS), communicated to me to establish a journal on ENERGY AND THERMOFLUIDS ENGINEERING (ETE). The journal will focus on three main areas: renewable energy, conventional energy, and thermofluids engineering. Where authors will publish free of char...

Heat transfer is key to the survival of honey bee colonies (Apis mellifera L.) in the wide range of hot (e.g. sub-Saharan) and cool climates (e.g. maritime-temperate) in which they have evolved and adapted. Here, a validated computational fluid dynamics, conjugate heat transfer model was used to determine the heat transfer of honey bee colonies in...

Arbitrary shaping of temperature fields at the nanometer scale is an important goal in nanotechnology; this is challenging due to diffusive nature of heat transfer. In the present work, we have numerically demonstrated that spatial shaping of nanoscale temperature fields can be achieved by plasmonic heating of a single titanium nitride (TiN) nanost...

With the every-increasing demands for miniaturization, the efficient cooling techniques for axial-flux permanent magnet synchronous machines (AF-PMSMs) have attracted great attentions. In this paper, the thermofluid behaviors of a 7-kW 4000-rpm AF-PMSM are numerically investigated based on a coupled model, and the computations are validated by ther...

The regenerator is one of the most important elements of a thermal machine operating in an alternating flow regime. The present study constituted an experiment on the dynamic characterization of different metallic regenerators crossed by alternating air flow. During an experiment, gas temperature, velocity, and pressure were measured at both ends o...