Explore the vast range of titles available.

This article explores the crucial function that Shell and Tube Heat Exchangers (STHE) play in a variety of industrial applications. This research uses a three-dimensional computational fluid dynamics (CFD) simulation to model turbulent fluid flow and evaluate the performance of different baffle angle configurations. The study evaluates performance indicators such as overall heat transfer coefficient (OHT), shell side heat transfer coefficient (HTC), pressure drop (PD), and PEC (Performance Evaluation Criteria), this study evaluates their effect on Segmental STHE performance. The findings indicate that the PD in the shell section rises by a range of 56.8–60.9% for baffles inclined 0° to 30°. Additionally, compared to the 0° inclined baffles, the 30° inclined baffles exhibit a greater OHT of 4.5–6%. The PEC values that are determined for each type of baffle are the most crucial aspect to take into account while selecting the optimal STHE. The 25° inclined baffles have been selected as the most advantageous baffles due to their improved performance, as seen by their different PEC values. In the subsequent stage of the study, researchers investigated how changing the quantity of superior baffles (inclined) affects the STHE’s efficiency. As the number of baffles was increased from 4 to 10, the OHT rose by 14.5–17% and the PD increased by 138.63–141.7%. This thorough simulation revealed that the STHE with the 8 inclined baffles had the highest PEC value and was therefore the most appropriate STHE.

To investigate the influence of baffle cut height on the performance of shell-and-tube heat exchangers, numerical simulations were conducted to analyse the shell-side heat transfer and flow characteristics of conventional segmental baffles and Cinquefoil Orifice Mixed-Flow Baffle (COMFB) under varying cut heights (0.15 D –0.4 D ). The results indicate that when the cut height increases, both the shell-side Nusselt number ( Nu ) and pressure drop (Δ P ) exhibit decreasing trends. However, the comprehensive performance PEC ( Nu / ΔP 1/3 ) of both structures does not change monotonically and gives a peak value at a cut height of about 0.3 D . Comparing the segmental baffle heat exchangers, COMFB heat exchangers behaves quite better with having much higher heat transfer efficiency and PEC and less flow resistance and energy dissipation.

Purpose This paper aims to investigate the fluid flow and heat transfer of a laboratory shell and tube heat exchanger that are analyzed using computational fluid dynamic approach by SOLIDWORKS flow simulation (ver. 2015) software. Design/methodology/approach In this study, several types of baffle including segmental baffle, butterfly baffle, helical baffle, combined helical-segmental baffle, combined helical-disk baffle and combined helical-butterfly baffle are examined. Two important parameters as the heat transfer and pressure drop are evaluated and analyzed. Based on obtained results, segmental baffle has the highest amount of heat transfer and pressure drop. To assess the integrative performance, performance coefficient defines as “Q/Δp” is used. Findings This investigation showed that among the presented baffle types, the heat exchangers equipped with disk baffle has the highest heat transfer. In addition, in the same mass flow rate, the performance coefficient of the shell and tube heat exchanger equipped with helical-butterfly baffle is the highest among the proposed models. Originality/value After combined helical-butterfly baffle the butterfly baffle, disk baffle, helical-segmental baffle and helical-disk baffle show their superiority of 35.12, 25, 22 and 12 per cent rather than the common segmental baffle, respectively. Furthermore, except for the combined helical-disk baffle, the other type of combined baffle have better performance compare to the basic configuration (butterfly and segmental baffle).

In stirred tank reactors, especially without using baffles, the liquid surface can deform, which in stirring technology is referred to a vortex. These vortices can be advantageous for some mixing tasks, such as obtaining emulsions, they can also impair a consistent product quality. Therefore, it is important for the production and process industry, to know whether a vortex occurs or not. Prediction is only possible with an outdated dimensionless baffle index and research on vortex formation with baffles is limited. In this study, two industrially important axial stirring systems—Propeller and Pitched-blade turbine—with different baffle geometries (rectangular, cylindrical, triangular) and numbers are assessed in regard to power input, vortex characteristics (depth, width, volume) and baffle state prediction. Power is recorded using strain gauges, while vortices are evaluated using an optical image evaluation method. The final vortex result is made dimensionless, accessible to the industry to enable improved predictions about the size of the vortices on an industrial scale in order to make the stirred tanks more economical and sustainable. Furthermore, an initial improvement of the baffle index for the investigated stirrers is given, because the original index incorrectly predicts the baffle state in 12.5% of cases.

Rapid granular flows are one of the most catastrophic geo-disasters frequently encountered in mountainous areas. The baffle structure has been demonstrated to be an effective measure for decreasing the destructivity of such geo-disasters. In this paper, a flow–baffle interaction model based on the 3D discrete element method is adopted to assess the baffle performance, hoping to facilitate the optimal design of baffles. A multiple-indicator-based framework, which covers three aspects and six metrics, is proposed and used to thoroughly and quantitatively assess the energy dissipation capacity, deposition regulation function, and failure potential of the baffle structure considering the particle size and baffle shape effect. Results indicate that the particle size significantly affects the baffle performance, and several linear relationships are proposed to account for the effect of the particle size, which may serve to improve engineering structural design. The square baffle performs better than the triangular baffle even though they have identical transverse blockage. Investigation of the patterns of the force chain distribution in granular flows confirms that the flow–baffle interaction is controlled by the evolution of force chains. The particle size and baffle shape effect can be explained by the difference in stability of arches that form during flow–baffle interaction. In addition, the quantification of energy loss due to inelastic contact between particles and baffles reveals that enhanced particle–particle interaction is the dominant energy dissipation mechanism, accounting for more than 80–90% of the total energy loss.

Baffles and check-dam systems are often used as granular flow (rock avalanches, debris flows, etc.) control structures in regions prone to dangerous geological hazards leading to massive landslides. This paper explores the use of numerical modelling to simulate large volume granular flow and the effect of the presence of baffles and check dam systems on granular flow. In particular, the paper offers a solution based on the smoothed particle hydrodynamics numerical method, combined with a modified Bingham model with Mohr–Coulomb yield stress for granular flows. This method is parallelised at a large scale to perform high-resolution simulations of sand flowing down an inclined flume, obstructed by rigid control structures. We found that to maximise the flow deceleration ability of baffle arrays, the design of baffle height ought to reach a minimum critical value, which can be quantified from the flow depth without baffles (e.g. 2.7 times for frictional flows with friction angle of 27.5°). Also, the check-dam system was found to minimise run-out distances more effectively but experiences substantially higher forces compared to baffles. Finally, flow-control structures that resulted in lower run-out distances were associated with lower total energy dissipation, but faster kinetic energy dissipation in the granular flows; as well as lower downstream peak flow rates.

Improving heat transfer is a critical subject for energy conservation systems which directly affects economic efficiency of these systems. There are active and passive methods which can be employed to enhance the rate of heat transfer without reducing the general efficiency of the energy conservation systems. Among these methods, passive techniques are more cost-effective and reliable in comparison with active ones as they have no moving parts. To achieve further improvements in heat transfer performances, some researchers combined passive techniques. This article performs a review of the literature on the area of heat transfer improvement employing a combination of nanofluid and inserts. Inserts are baffles, twisted tape, vortex generators, and wire coil inserts. The progress made and the current challenges for each combined system are discussed, and some conclusions and suggestions are made for future research.

The present study focuses on the heat transfer within a ventilated porous enclosure saturated with a hybrid nanofluid, with the added influence of a magnetic field. The working hybrid nanofluid used in the study is consisting of copper and alumina nanoparticles suspended in water. This research covers two different types of geometries based on their opening ports. The cavity contains two vertical heating baffles placed near the inlet and outlet ports. The objective of this research is to understand how the presence of these heated obstacles, along with the distinct properties of the hybrid nanofluid and porous medium in the existence of magnetic field, influence the heat transfer and flow patterns within the cavity. The discretized governing equations are solved using finite difference method along with the boundary conditions. Irrespective of various parameters such as Solid volume fraction ( [Formula omitted]), Darcy number (Da), Hartmann number (Ha), length of heating baffles ( [Formula omitted]) and Rayleigh number (Ra), configuration BT consistently demonstrates higher heat transfer. The heat transfer near the heated baffle is maximized when [Formula omitted] and [Formula omitted] in configuration BT. For [Formula omitted] and [Formula omitted] in configuration BT, the highest heat transfer along the right sidewall is achieved with 25%; while, [Formula omitted] is optimal at [Formula omitted]. The findings derived from this investigation hold significant relevance for a multitude of engineering domains, encompassing energy systems, heat exchangers, and the extraction of geothermal energy.

An equivalent analytical model of sloshing in a two-dimensional (2-D) rigid rectangular container equipped with multiple vertical baffles is presented. Firstly, according to the subdomain partition approach, the total liquid domain is partitioned into subdomains with the pure interface and boundary conditions. The separation of variables is utilized to achieve the velocity potential for subdomains. Then, sloshing characteristics are solved according to continuity and free surface conditions. According to the mode orthogonality of sloshing, the governing motion equation for sloshing under horizontal excitation is given by introducing generalized time coordinates. Besides, by producing the same hydrodynamic shear and overturning moment as those from the original container-liquid-baffle system, a mass-spring analytical model of the continuous liquid sloshing is established. The equivalent masses and corresponding locations are presented in the model. The feasibility of the present approach is verified by conducting comparative investigations. Finally, by utilizing normalized equivalent model parameters, the sloshing behaviors of the baffled container are investigated regarding baffle positions and heights as well as the liquid height, respectively.