Flow Behavior Characteristics Research Articles

Rheology characterization of ionic liquids under high pressure and high temperature

Ionic liquids (ILs) are liquid salts that exist at or below ambient temperatures and are composed of ion pairs. They offer promising alternatives to toxic, hazardous, highly flammable, and volatile solvents in various applications such as solution preparation, dispersion, gel formation, composites, and polymer melts. ILs possess unique and interesting characteristics, including excellent chemical and thermal stability and low vapor pressures. Understanding the rheological properties of ILs is essential to optimizing IL performance. This paper presents a comparative analysis of the rheological properties of two ionic liquids, NHexylpyridinium tetrafluoroborate (HPyBF4) and NHexylpyridinium bromide (HPyBr), under different shear rates, temperatures, and pressures. Rheological measurements were performed under varying controlled pressure and temperature conditions. The experimental investigation covered a pressure range of 689–12,411 kPa [100–1800 psi] and a temperature range from room temperature up to 522 kelvin (K) [480°F]. The primary objective is to explore and compare the flow behavior and viscoelastic characteristics of HPyBF4 and HPyBr under high-pressure and high-temperature conditions. The experimental data showed that HPyBF4 and HPyBr exhibited shear-thinning behavior, and pressure had an insignificant effect on rheology compared to the temperature effect. Under the same testing conditions, HPyBr showed higher shear stress and viscosity than HPyBF4. This research significantly contributes to the improved understanding of the rheological behavior of these specific ionic liquids and their suitability for diverse industrial and scientific applications, particularly in high-pressure and high-temperature environments.

Study on the plume flow behavior and air entrainment characteristics of co-burning fires

In most of the fire accidents, there is large oil layer leaking into the fire dike and multiple fire points burning simultaneously. A series of numerical simulations for co-burning of a dike and double tanks (co-burning) with different spacing S have been conducted to study the plume flow behavior and air entrainment characteristics. The simulation results show that there is a conical fuel-rich region on the upper rim of the tank which results in the entrained air to flow circularly along the surface of the conical region. With the increase of S, the restriction effect of tank sidewall on air entrainment from environment enhances, while the restriction degree of air entrainment in the middle area of the double tanks decreases, affecting the distribution of plume velocity field and temperature field. And under the coupling effect of them, the tilt degree of tank flame decreases with the increase of S (from 0.3 m to 0.7 m). The air entrainment restriction coefficient , are introduced to characterize the restriction effect of air entrainment between the external dike fire and the double tank fires. Based on this, a co-burning plume entrainment model has been established, which can be applicable to different spacing S.

Dynamics of the ohmic heating and chemically reactive time-dependent flow of magnetized Casson fluid inside a rectangular pipe

Chemical reaction and ohmic heating can significantly influence the flow behavior and heat transfer characteristics in industrial processes involving non-Newtonian fluids. These processes include polymer processing, food processing, and manufacturing processes where non-Newtonian fluids are commonly encountered. Therefore, the impacts of chemical reaction and ohmic heating on the unsteady flow of an incompressible magnetized non-Newtonian Casson liquid through a rectangular pipe with a variable pressure gradient is scrutinized in this article. The impacts of heat generation/absorption and viscous dissipation are also incorporated through the energy equation. The numerical simulations of partial differential equations (PDEs) are acquired utilizing the finite difference method with the incorporating relaxation (SOR) algorithm. The impacts of dissimilar imperative parameters on various flow fields are scrutinized through graphs. Outcomes indicate that liquid velocity decreases with enhancing values of the Casson parameter. Furthermore, the liquid temperature has an enhancing behavior with the impact of the heat source/sink parameter. Comparisons of numerical results with previously published results show an excellent agreement. This kind of research may find specific industrial and medical utilizations such as glass manufacturing, crude oil purification, lubrication, paper production, blood transport study in cardiovascular design, etc.

Research on the Population Flow and Mixing Characteristics of Pelleted Vegetable Seeds Based on the Bonded-Particle Model

In order to precisely reproduce the precise seeding process of the population in the air-suction seed-metering device, it is necessary to execute accurate modeling of seed particles using the bonded-particle model, in combination with the discrete element method (DEM) and computational fluid dynamics (CFD). Through the repose angle, slope screening, rotating container, and particle sedimentation experiments, in this paper, the influence of the filling accuracy of the bonded-particle model on the flow behavior and mixing characteristics of the seed population was first explored based on EDEM software. The viability of the suggested modeling approach for pelleted vegetable seeds, as described in this study, was confirmed by comparing experimental and simulation outcomes. The surface roughness values obtained from the studies above were utilized to assess the accuracy of the bonded-particle model in filling. Additionally, a mathematical technique for determining the surface roughness was provided. Furthermore, an analysis of the multiple contacts in the bonded-particle model was also performed. The results indicated that the simulation results closely matched the experimental data when the number of sub-spheres in the bonded-particle model was equal to or more than 70, as measured by the standard deviation. In addition, the most optimal modeling scheme for the pelletized vegetable seed bonded-particles, based on the cost of coupling simulation, was found to be the bonded-particle surface roughness (BS) with a value of 0.1. Ultimately, a practical example was utilized to demonstrate the utilization of the pelleted vegetable seed bonded-particle model and the DEM-CFD coupling approach in analyzing the accuracy of the seeding process in the air-suction seed-metering device. This example will serve as a valuable reference point for future field studies.

Dissipative Non-Slip MHD Nanofluid Flow with Variable Viscousity and Thermal Conductivity in the Presence of Arrhenius Chemical Reaction

This research investigates the intricate dynamics of dissipative non-slip magnetohydrodynamic (MHD) nanofluid flow, characterized by variable viscosity and thermal conductivity, under the influence of an Arrhenius chemical reaction. The inclusion of the Arrhenius chemical reaction adds complexity through heat generation or absorption, impacting temperature and concentration gradients. The study is motivated by the extensive applications of nanofluids in engineering and industrial processes, where precise control of heat and mass transfer is critical. We develop a comprehensive mathematical model that incorporates the variable properties of the nanofluid, the effects of the Lorentz force due to the applied magnetic field, and the temperature-dependent reaction rates dictated by the Arrhenius equation. The formulated governing equations were non-dimensionalised to identify the flow governing parameters. Finite Element Method (FEM), grid generation, solution algorithms, and post-processing to analyse velocity, temperature, and concentration distributions were used to obtain the numerical methods to solve fluid flow problems based on the Navier-Stokes equations, involving concepts of discretization. pdsolve subpackage in Maple 2023 was used to numerically solve PDEs with specific initial and boundary conditions, incorporating the plot and display commands for graphical analysis, and the results are presented and discussed. The findings reveal that the interplay between parameters like Hartmann number, Darcy parameter, and heat generation or absorption profoundly influences flow behaviour and thermal characteristics. The reactivity parameter is crucial, dictating the rate of chemical reactions and affecting system dynamics. This research enhances understanding of the interdependencies among fluid properties, chemical reactions, and external parameters in nanofluid flows.

Flow Behavior Characterization of DNA Molecules in Passive Nanofluidic Devices†

This work aims to develop a method for analyzing the dynamic flow of single DNA molecules through nanochannels in fluidic chip which work passively. For this purpose, a two‐laser system was used, which is coupled into a fluorescence microscope and can detect labeled DNA molecules using a single photon counter for signal read‐out in real‐time. The two laser spots are focused at different points of the nanochannel, and can be used to obtain the speed and molecular extension of the DNA. For example, a velocity of 1.82 μm/ms and a spatial extension of 0.9 μm were determined for pUC18/19 DNA (2686 bp) in a nanochannel with a width and depth of 200 nm × 100 nm and a length of 10 μm. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

Flow behavior and size characteristics of microbubble swarm in a HiGee-aided fixed bed reactor with different packed structures

A HiGee-aided fixed bed reactor (HFBR) has great potential for catalytic hydrogenation with hydrogen microbubble swarm for gas–liquid mass transfer intensification. However, the flow behavior and size characteristics of microbubble swarm in the catalyst bed of HFBR still remain unclear. In this work, the flow characteristics of microbubble swarm in different packed structures of catalysts and catalyst supports had been fully analyzed by the high-speed photography and image processing technology. The optimal ratio of packing heights for the bottom of the catalyst supports was Φ13 mm: Φ6 mm: Φ3 mm = 3: 1: 1, while the top of the catalyst supports was packed with single catalyst support of Φ6 mm. Furthermore, a dimensionless correlation based on the experimental results had been developed to predict (d32)o/(d32)i with deviations within ±15 %. The effective interfacial area of HFBR was 0.6 ∼ 6.1 × 103 m2/m3 under the experimental conditions.

Influence of Geometric Characteristics onWaterFlow and Solute Transport atFracture Intersections.

Laboratory experiments and numerical simulations were performed to explore the influence of intersection geometry on fluid flow and solute transport in fractures. Fractures were engraved and sealed into an acrylic plate and two orthogonal intersections with different geometry were constructed. The effects of curvature and relative shear displacement at intersections on preferential flow and solute transport were investigated. By solving the Navier-Stokes (NS) equation, the fluid mixing and solute distribution were predicted. The results showed that the geometric characteristics at the intersection have a significant effect on the preferential flow and solute distribution. The results agreed well with the experimental results, in terms of flow direction, preferential flow rate, and heterogeneous solute distribution. With an increase in curvature, the flow difference between the two outlets increases gradually. Increasing curvature can reduce the preferential flow and weaken the inhomogeneity of solute distribution. An increase of relative shear displacement decreases the pressure gradient and flow rate at the entrance of the two branch fractures, and thereby increases preferential flow and inhomogeneity of solute distribution. The results provide a basis and reference for further exploring the relationship between the geometric characteristics of fracture intersections and flow behaviors.

EXPERIMENTAL STUDY ON TWO-PHASE NONLINEAR OSCILLATION BEHAVIOR OF MINIATURIZED GRAVITATIONAL HEAT PIPE

An experimental study on oscillation behavior of vapor-liquid two-phase flow in an ethanol-filled aluminum miniaturized gravitational heat pipe with parallel rectangular channels is carried out. The nonlinear oscillation behavior and oscillation characteristics of two-phase flow in the oscillation state are qualitatively analyzed. In addition, the nonlinear oscillation characteristic of the wall temperature is revealed. Furthermore, the influence of heat load on temperature oscillation characteristics is further analyzed. The research shows that the independent oscillation in a single channel characterized by the random formation and oscillation of liquid plug in a single channel is the typical oscillation behavior of two-phase flow under medium heat load (<i>Q</i> = 28 W). In addition, the interaction on oscillation of liquid plugs between adjacent channels is small. For high heat load (<i>Q</i> = 45 W), the vapor pressure difference at both ends of the liquid plug has a more important role in promoting the liquid plug, the superposition of the liquid plug oscillation in single channel and the oscillation between adjacent channels forms the interference oscillation in adjacent channels. For interference oscillation in adjacent channels, under coupling erosion of the liquid plug in a single channel and the liquid plugs in adjacent channels, with increase of heat load (<i>Q</i> increases from 38 W to 45 W), the dominant frequency of oscillation for independent oscillation in a single channel increases (from 2.5 Hz to 4.2 Hz), and the larger driving force caused by heat load increase enhances the oscillation of liquid plug in a single channel and weakens the oscillation of liquid plug in different channels for interference oscillation in adjacent channels.

Establishing the hot working window for the forging of S32906 super duplex stainless steel through considering deformation parameter sensitivities

The evaluation of the hot workability of the super duplex stainless steel (SDSS) material still lacks scientific and theoretical basis, leading to the frequent occurrence of unacceptable defects in its forgings. In this study, a novel method for estimating the hot workability of S32906 SDSS was proposed and verified through forging. Firstly, the flow behavior and microstructural characteristics were demonstrated by conducting isothermal compression tests at the deformation temperature from 1000 °C to 1250 °C and the strain rate from 0.01 s−1 to 10 s−1. The influence of microstructure on flow and work hardening behaviors was correlated and displayed. Then, based on the deformation characteristics presented through the variations of strain rate sensitivity (SRS) and deformation temperature sensitivity (DTS) coefficients, the SRS and DTS maps were constructed and overlaid for obtaining the hot working window. Ultimately, a large plate type forging of S32906 SDSS applied in engineering was used to verify the applicability of the obtained window. The new method can provide an in-depth understanding of hot workability and enable control of the forming and microstructural properties for this unique material.

Numerical Investigation of Inner Flow Characteristics of a Prototype Pump Turbine with a Single Pier in Draft Tube at Part Load Conditions

Pump turbines operate under various off-design conditions, resulting in complex internal flow patterns. This study employs Reynolds-averaged Navier–Stokes (RANS) numerical methods to investigate the flow characteristics of a prototype pump turbine with a single draft tube pier in turbine mode, and then, the flow characteristics inside the draft tube are discussed with emphasis. Asymmetry between the pier-divided draft tube passage flows is inevitable due to the elbow section’s curvature. Most of the fluid flows out of one passage, while vortex motion dominates the interior of the other one, resulting in completely different pressure fluctuation characteristics for the two flow passages. The large-flow passage is mainly characterized by the wide band in the frequency domain, corresponding to the recirculation zone, while some of the measured points in the low-discharge passage exhibit frequency splitting under kinematic progression. Further analysis demonstrates a low-frequency peak corresponding to the complementary shape between the vortex rope and the recirculation zone. This work elucidates the effects of the pier on the flow behavior and pressure fluctuation characteristics inside the draft tube and fills the research gap on piers in the field of pump turbines.

42CrMo4 steel flow behavior characterization for high temperature closed dies hot forging in automotive components applications

The application of new forming processes as the high temperature hot forging in closed dies in an industrial environment still requires further investigation due to the lack of flow stress data at these temperatures. To determine the flow behavior of the 42CrMo4 steel at high temperatures hot compression tests have been carried out in a Gleeble® 3800 thermomechanical tester for a temperature range that covers the material behavior from the hot forging until the Nil Ductility Temperature (1250 °C-1375 °C) and for three different orders of magnitudes for the strain rates (0.1 s−1, 1 s−1 and 10 s−1). Then, the Hansel-Spittel model, widely used in automotive commercial software as FORGE®, has been employed to obtain the adequate constants of the constitutive equation for high temperatures.Finally, the newly obtained flow behavior model has been validated by comparison between experimental and simulated compression tests and by the process simulation of a commercial automotive component comparing the results of the simulation with the already made experimental tests in a laboratory cellule of the new technology.Hence, this paper shows the procedure for the determination and the obtention of a new constitutive model for the 42CrMo4 steel flow stress characterization at a temperature range between 1250 °C–1375 °C. This will contribute in the knowledge of material flow stress behavior models at high temperatures and will allow the prediction or simulation of high temperature hot forging in closed dies processes, enhancing the possibility of the application of these technologies from an industrial point of view.

Numerical investigation of nanofluid buoyant flow behavior and heat transfer characteristics in annular-shaped enclosure with internal baffle

PurposeNatural convection in finite enclosures is a common phenomenon in various thermal applications. To provide the thermal design guidelines, this study aims to numerically explore the potential of using internal baffles and nanofluids to either enhance or suppress heat transport in a vertical annulus. Furthermore, the annular-shaped enclosure is filled with aqueous-silver nanofluid and the effects of five distinct nanoparticle shapes are examined. In addition, the influence of baffle design parameters, including baffle position, thickness and length, is thoroughly analyzed.Design/methodology/approachThe finite difference method is used in conjunction with the alternating direction implicit and successive line over relaxation techniques to solve nonlinear and coupled partial differential equations. The single phase model is used for nanofluid which is considered as a homogeneous fluid with improved thermal properties. The independence tests are carried out for assessing the sufficiency of grid size and time step for obtaining results accurately.FindingsThe baffle dimension parameters and nanoparticle shape exhibit significant impact on the convective flow and heat transfer characteristics, leading to the following results: sphere- and blade-shaped nanoparticles demonstrate around 30% enhancement in the heat transport capability compared with platelet-shaped nanoparticles, which exhibit the least. When considering the baffle design parameter, either a decrease in the baffle length and thickness or an increase in baffle height leads to an improvement in heat transport rate. Consequently, a threefold increase in baffle height yields a 40% improvement in thermal performance.Originality/valueUnderstanding the impact of nanoparticle shapes and baffle design parameters on flow and thermal behavior will enable engineers to provide valuable insight on thermal management and overall system efficiency. Therefore, the current work focuses on exploring buoyant nanofluid flow and thermal mechanism in a baffled annular-shaped enclosure. Specifically, an internal baffle that exhibits conductive heat transfer through it is considered, and the impact of baffle dimensions (thickness, length and position) on the fluid flow behavior and thermal characteristics is investigated. In addition, the current study also addresses the influence of five distinct nanoparticle shapes (e.g. spherical, cylindrical, platelet, blade and brick) on the flow and thermal behavior in the baffled annular geometry. In addition to deepening the understanding of nanofluid behavior in a baffled vertical annulus, the current study contributes to the ongoing advancements in thermal applications by providing certain guidelines to design application-specific enclosures.

Computational fluid dynamics modeling and mass transfer study of an in situ gas production process

AbstractThe oxidation of cyclohexanone with nitric acid in microreactors, as a representative chemical reaction with in situ gas production, was selected as the model reaction for computational fluid dynamics (CFD) modeling. The reaction kinetics was coupled with the CFD model by user‐defined functions (UDFs) to obtain the velocity field of liquid phase, the concentration field of products, and the temperature field of gas–liquid phases during the reaction process. The simulation results were then validated by the experimental data. Based on the established model, the fluid flow behavior and mass transfer characteristics during the in situ gas production process in a microreactor were further analyzed. Finally, the effects of channel diameter and bubble velocity on gas–liquid interfacial mass transfer were investigated. This work provides an effective method for studying in situ gas production processes through modeling and simulation, which is valuable in the design and optimization of tubular reactors.

Analysis of vortex structures evolution and aeroacoustic characteristics in the ultra-high-speed elevator ring-gap flow field

The continuous improvement of elevator speed has made the issue of aerodynamic noise in the hoistway more prominent. Previous research has usually focused on the characteristics of aerodynamic loads and related safety issues, and little attention has been paid to the problem of flow-induced noise. This paper established a three-dimensional geometric configuration of the ultra-high-speed elevator to study the flow behavior and aerodynamic acoustic characteristics in the hoistway using well-validated large eddy simulations. Firstly, we analyzed the unsteady flow behavior in the ring-gap flow field using large eddy simulations and captured the transient vortex structure in the flow field using the Q-criterion. We then predicted the far-field aerodynamic noise of the elevator car using the Lighthill-Curle aerodynamic acoustic equations. The results showed that the factors affecting the sound source intensity of the elevator car include the shedding position and intensity of the vortex structures. By adjusting the shedding position and reducing the intensity of the vortex structure, the sound source intensity of the elevator car wall could be effectively controlled. The change of the blocking ratio could not affect the attenuation of aerodynamic noise in the hoistway, but the increase of the blocking ratio could lead to an increase in the turbulent kinetic energy intensity and peak SPL in the hoistway. Therefore, the blocking ratio should be kept within 0.65 when designing the hoistway structure dimensions.

Air pollution dispersion in Hail city: Climate and urban topography impact

Due to the rapid urbanization of many cities around the world, industrial manufacturing plants have been expanded quickly, leading to the discharge of large amounts of pollutants into the environment. Consequently, a significant deterioration in local air quality is recorded, representing a high health risk for the city's residents. In this context, the main objective of this work is to understand the dispersion of gas pollution in high-density urban environments, specifically the Hail region of Saudi Arabia. The simulations carried out with Ansys Fluent 19.0 were based on actual climatic conditions, with particular attention paid to accurately reproducing the exact topography of the study area. The main results concern the characterization of flow behavior and the dispersion of gas pollutants emitted by power plants. Several factors, including building geometry and wind speed, are examined. The study reveals that for a reference wind speed of more than 7 m/s, gaseous pollution exhibits a significant tendency to accumulate within buildings, resulting in significant concentrations.

Influence of high strain rate deformation on the microstructure and mechanical behavior of NiCoCrFe high entropy alloy

The paper reported a high-entropy alloy, NiCoCrFe, which was produced in a Vacuum Induction Melting (VIM) furnace. In order to homogenize the microstructure, the as-cast ingot was rolled, annealed and machined to appropriate dimensions. Then the Split Hopkinson Pressure Bar (SHPB) was used to evaluate the specimens under various strain rates. True stress–strain curves of this test showed similar patterns in all strain rates, with two peaks that can be assigned to the competition between strain hardening and thermal softening. Modified Johnson–Cook model applied to characterize flow behavior of the alloy. X-ray diffraction results indicated that the alloy was single-phase with FCC crystal structure at the casting condition, after thermomechanical operation and after high-strain rate tests. The specimens were further examined by EBSD. The results indicated the impressive presence of twins in the samples deformed at strain rate of 1500 s−1, confirms the significant contribution of twinning in the strengthening process; Regarding the low SFE of the mentioned alloy, it can be said that Twin-Induced Plasticity (TWIP) has occurred. By strain rate enhancement to 3000 s−1, finer and elongated grains were observed while twinning decreased because of SFE increase as a result of temperature elevation due to adiabatic heating during deformation. According to KAM map, there was strain gradient in mentioned sample, which results in production of GNDs and GNDs pile-up leading to strain hardening by creating obstacles to further slip. Moreover, in the hat-shaped samples, which used for shear localization resistance evaluations, bundles of nano-twins were observed whose formation largely prevented strain localization and make the above alloy suitable for applications exposed to high-speed impacts.

A Pore-Scale Model for Electrokinetic In situ Recovery of Copper: The Influence of Mineral Occurrence, Zeta Potential, and Electric Potential

Electrokinetic in-situ recovery is an alternative to conventional mining, relying on the application of an electric potential to enhance the subsurface flow of ions. Understanding the pore-scale flow and ion transport under electric potential is essential for petrophysical properties estimation and flow behavior characterization. The governing physics of electrokinetic transport is electromigration and electroosmotic flow, which depend on the electric potential gradient, mineral occurrence, domain morphology (tortuosity and porosity, grain size and distribution, etc.), and electrolyte properties (local pH distribution and lixiviant type and concentration, etc.). Herein, mineral occurrence and its associated zeta potential are investigated for EK transport. The new Ek model which is designed to solve the EK flow in complex porous media in a highly parallelizable manner includes three coupled equations: (1) Poisson equation, (2) Nernst–Planck equation, and (3) Navier–Stokes equation. These equations were solved using the lattice Boltzmann method within X-ray computed microtomography images. The proposed model is validated against COMSOL multiphysics in a two-dimensional microchannel in terms of fluid flow behavior when the electrical double layer is both resolvable and unresolvable. A more complex chalcopyrite-silica system is then obtained by micro-CT scanning to evaluate the model performance. The effects of mineral occurrence, zeta potential, and electric potential on the three-dimensional chalcopyrite-silica system were evaluated. Although the positive zeta potential of chalcopyrite can induce a flow of ferric ion counter to the direction of electromigration, the net effect is dependent on the occurrence of chalcopyrite. However, the ion flux induced by electromigration was the dominant transport mechanism, whereas advection induced by electroosmosis made a lower contribution. Overall, a pore-scale EK model is proposed for direct simulation on pore-scale images. The proposed model can be coupled with other geochemical models for full physicochemical transport simulations. Meanwhile, electrokinetic transport shows promise as a human-controllable technique because the electromigration of ions and the applied electric potential can be easily controlled externally.Graphical abstract

Experimental analysis of temperature and vapor core pressure for an annular heat pipe

The main contribution of this study is the effects of the operating conditions on the internal vapor pressure and temperature in an annular screen wick heat pipe, using distilled water as the working fluid. High-resolution pressure transducers, optical fiber distributed temperature sensors, and K-type thermocouples were employed to measure the internal and external temperatures as well as the local static pressures at different axial positions of the heat pipe. Temporal and frequency analysis using a one-dimensional continuous wavelet transform was performed on the differential pressure data to characterize flow behavior and infer the flow regime occurring within the heat pipe. The heat pipe was tested in multiple orientations with respect to the horizon (θ=0°, 45°, and 90°), heat loads (25, 50, and 75 W), and condenser coolant temperatures (Tw,in= 10 °C, 20 °C, and 30 °C). To estimate the vapor-phase flow friction factor for multiple Reynolds numbers, the Lockhart–Martinelli correlation was employed. This study provides critical experimental data and analyses for complex two-phase flow behavior in an annular wick heat pipe geometry. The thermal resistance and effective thermal conductivity were estimated as a function of the heat pipe orientation and power input. The experimental investigation revealed that power input and orientation influence both the internal vapor core and external surface temperatures, as well as the local pressure response. The outcomes from this study provide a valuable database that supports the advancement of heat pipe design, modeling, and validation.

A comprehensive numerical study on the fluid flow, thermal and exergetic performance of longitudinally ribbed spirally coiled tube with various shapes

The primary objective of this investigation is to examine the impact of rib configuration on flow behavior and heat transfer characteristics in a spiral tube with longitudinal ribs, through numerical simulations. Different cross-sectional shapes, including semicircular, V-shaped, trapezoidal, and rectangular ribs, are analyzed to assess the fluid flow, heat transfer, and exergetic efficiency of the tube. The findings indicate that incorporating longitudinal ribs of different cross-sectional forms substantially improves the fluid flow and thermal efficiency of the spirally coiled tube. An increase in rib depth leads to an accompanying rise in the Nusselt number, with improvements ranging from 18.4% to 27.9% for V-shaped and trapezoidal ribs, respectively. The spiral tube with rectangular shaped ribs exhibits the highest Nusselt number. Additionally, when the rib depth increases from 0.02 to 0.12 for the spiral tube with rectangular-shaped ribs, the THPP (Thermohydraulic performance parameter) experiences a significant increase of 38.1%. Also, the number of ribs (Nr) in the longitudinally ribbed spirally coiled tube has a crucial impact on its performance. Increasing the number of ribs results in higher heat transfer coefficients and Nusselt numbers for all tested rib shapes. However, the inclusion of more ribs leads to increased exergy destruction across all scenarios.