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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).

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.

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.

The effect of inside surface baffle installation conditions on the minimum impeller rotational speed for just the drawdown of floating solid NJD was investigated. The inside surface baffle condition is the condition in which a partial baffle is placed with a clearance between the baffle and the vessel wall. In this study, a baffle with an insertion length of 0.2 times the liquid height was used. Moreover, the effect of baffle angle on NJD was investigated. The NJD was measured visually at least three times. The results showed that the effect of the radial installation position of the inside surface baffle on NJD depended on the impeller position. In addition, even baffles placed parallel to the tangential flow were found to decrease NJD.

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.

A plasmonic metal-insulator-metal waveguide filter consisting of one rectangular cavity and three silver baffles is numerically investigated using the finite element method and theoretically described by the cavity resonance mode theory. The proposed structure shows a simple shape with a small number of structural parameters that can function as a plasmonic sensor with a filter property, high sensitivity and figure of merit, and wide bandgap. Simulation results demonstrate that a cavity with three silver baffles could significantly affect the resonance condition and remarkably enhance the sensor performance compared to its counterpart without baffles. The calculated sensitivity (S) and figure of merit (FOM) in the first mode can reach 3300.00 nm/RIU and 170.00 RIU−1. Besides, S and FOM values can simultaneously get above 2000.00 nm/RIU and 110.00 RIU−1 in the first and second modes by varying a broad range of the structural parameters, which are not attainable in the reported literature. The proposed structure can realize multiple modes operating in a wide wavelength range, which may have potential applications in the on-chip plasmonic sensor, filter, and other optical integrated circuits.

Electro-osmotic micromixers constitute a specialized class of active micromixers that apply alternating current (AC) to electrodes. This methodology promotes the formation of vortical structures within the fluid medium, resulting in a substantial increase in mixing homogeneity. In this study, the geometrical parameters of the electro-osmotic micromixer, for which two rigid baffles were implanted at the entrance, were optimized using the Taguchi method and response surface methodology (RSM). Data were obtained through a transient 2D model, simulated using COMSOL software based on the finite element method. After acquiring the optimized geometric parameters, the mixing index was assessed under various conditions, including inlet velocity, frequency, voltage, and phase lag of the alternating current. The optimized values of first baffle angle ( ), second baffle angle ( ), baffle length (L), the distance between baffles in the x direction (x), the distance between baffles in the y direction(y), and mixing chamber angle ( ) were obtained and resulted in a 10.58% improvement in the mixing process index. The implementation of rigid baffles improved the mixing index by 8%. Furthermore, increasing the applied voltage from 1 to 3 V resulted in a 27% average enhancement of the mixing index. A maximum mixing index of 99.37% was achieved at a phase lag, representing an average 20.1% improvement compared to the absence of a phase lag. This reflects an approximate 65% increase at the initial stage compared to the scenario without any phase lag.