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This paper is aimed at introducing a method for the division of development units of thick carbonate reservoirs. This method consists of eight steps, ranked according to impact weight, each of which is independent but intrinsically linked. When there is a conflict between studies in different steps, the results of the previous step take precedence. (1) Pressure is the most important and reliable data. When the wells with an abnormal pressure gradient in the same interval account for more than 60%, further division of the reservoir is appropriate. (2) Baffles are the second most important and reliable basis. When there are continuous baffles or poor reservoirs that encounter more than 80% wells, it is appropriate to further divide reservoirs. (3) Without the two mentioned above, but with an unconformity surface or discontinuity surface between two sequences, it is appropriate to treat these two sequences as two development units. (4) Without the three mentioned above, if the permeability above and below the sequence boundary differs by 10 or more times, reservoirs above and below the sequence boundary are appropriate as distinct development units. (5) When the thickness, continuity, distribution pattern, and microstructure of two adjacent sequences are significantly different, it is appropriate to treat these two sequences as two development units. (6) If the development units are based on sequences, check for homogeneity within the stratigraphy. If depositional facies or physical property discontinuities are present, the sequence would be reconsidered for subdivision. (7) The reserves in each development unit should account for more than 20% of that of the whole reservoir. (8) When the division of the development units is complete, it needs to be examined to ensure that there is a consistent structure, fluid property, and free water level. If inconsistencies exist, then subdivision is considered. The method was successfully applied to A oilfield, Central Arabian Basin, in combination with the cores, cast thin sections, regular or special core analysis, wireline logging data from 450 wells, formation pressure from 63 wells, and more than 100 wells with a production logging test. The Mishrif reservoir was divided into four development units, in which different well patterns and well types were deployed. The improved development effect proves that the division of development units for thick bioclastic limestone reservoir is reasonable. [ABSTRACT FROM AUTHOR]

This work is experimental investigation on the impact of rectangular baffles on the thermo-hydraulic performance of a solar thermal collector. The study was conducted under moderate weather conditions and six cases were studied, including 2M135, 6M135, 10M135, 14M135, 18M135, and a smooth plate case. The results showed that the number and placement of baffles plays a crucial role in improving heat transfer and the best cases in terms of thermal performance were cases V and IV, with maximum values of h = 15.84 W/m2.k, and h = 17.46 W/m2k. The study also found that the heat transfer was greatest at the beginning of the channel and decreased towards the end. The highest thermal efficiency was recorded in case 18M135 with a maximum value of Ƞ=0.73.

The aim of the present work is to investigate the performance indication and flow of a counter heat device using different baffle configurations numerically. This research illustrates the consequence of segmental stumps and wavy cross-section stumps with varying wave numbers and amplitude. The governing equations of energy and Navier-Stokes equations were solved using the Computational Fluid Dynamics (CFD) software package FLUENT 22R1, employing the finite volume method. The SIMPLE algorithm with second-order upwind discretization for the convection term was used for velocity and pressure calculations. Different cold water rates of flow (2, 4, 6, and 8 L/min) at 23℃ through shell and Constand hot water flow rate at 1 LPM at 50℃ were analysed for their effect on heat transfer efficiency. The heat exchanger's thermal performance was comparing its duty with various baffle configurations to its performance without baffle. The research results indicate that installing baffles increased the heat exchanger's effectiveness (ε)., with the enhancement ratio (ε/εNE) reaching 1.2 and 1.23 for segmental and wavy baffles respectively compared to no baffle. On the other hand, the overall heat transfer coefficient (Uo) showed an improvement with baffles, achieving a performance increase of up to 1.38 at 8 LPM for Wavy baffles with wave number and amplitude (15 and 3 mm) respectively. The pressure drop in the system increased to 406 Pa at wavy baffles (15 and 3 mm) of 6 LPM. The maximum amount of exergy destruction being approximately 0.29 at 8 LPM for segmental. The results providing insights into optimal baffle design for specific applications. [ABSTRACT FROM AUTHOR]

The assessment of scour depth downstream of weirs holds paramount importance in ensuring the structural stability of these hydraulic structures. This study presents groundbreaking experimental investigations highlighting the innovative use of baffles to enhance energy dissipation and mitigate scour in the downstream beds of rectangular piano key weirs (RPKWs) and trapezoidal piano key weirs (TPKWs). By leveraging three state-of-the-art supervised machine learning algorithms—multi-layer perceptron (MLP), extreme gradient boosting (XGBoost), and support vector regression (SVR)—to estimate scour hole parameters, this research showcases significant advancements in predictive modeling for scour analysis. Experimental results reveal that the incorporation of baffles leads to a remarkable 18–22% increase in energy dissipation and an 11–14% reduction in scour depth for both RPKWs and TPKWs. Specifically, introducing baffles in RPKWs resulted in a noteworthy 26.7% reduction in scour hole area and a 30.3% decrease in scour volume compared to RPKWs without baffles. Moreover, novel empirical equations were developed to estimate scour parameters, achieving impressive performance metrics with an average R2 = 0.951, RMSE = 0.145, and MRPE = 4.429%. The MLP models demonstrate superior performance in predicting maximum scour depth across all scenarios with an average R2 = 0.988, RMSE = 0.035, and MRPE = 1.036%. However, the predictive capabilities varied when estimating weir toe scour depth under diverse circumstances, with the XGBoost model proving more accurate in scenarios involving baffled TPKWs with R2 = 0.965, RMSE = 0.048, and MRPE = 2.798% than the MLP and SVR models. This research underscores the significant role of baffles in minimizing scouring effects in TPKWs compared to RPKWs, showcasing the potential for improved design and efficiency in water-management systems. [ABSTRACT FROM AUTHOR]

This work is experimental investigation on the impact of rectangular baffles on the thermo-hydraulic performance of a solar thermal collector. The study was conducted under moderate weather conditions and six cases were studied, including 2M135, 6M135, 10M135, 14M135, 18M135, and a smooth plate case. The results showed that the number and placement of baffles plays a crucial role in improving heat transfer and the best cases in terms of thermal performance were cases V and IV, with maximum values of h = 15.84 W/m2.k, and h = 17.46 W/m2k. The study also found that the heat transfer was greatest at the beginning of the channel and decreased towards the end. The highest thermal efficiency was recorded in case 18M135 with a maximum value of n = 0.73. [ABSTRACT FROM AUTHOR]

This study investigates the impact of baffles on fuel sloshing behavior within truck fuel tanks using numerical simulations. The volume of the fluid multiphase model is employed to analyze the flow dynamics of 25% diesel fuel in a 250 L tank, modeled in a 3D domain. Two configurations were compared: a tank with baffles and one without. The primary focus is to analyze fuel distribution within the intake port region during vehicle acceleration and deceleration maneuvers. The simulated scenario mimics a realistic driving situation. The vehicle accelerates from 0 km/h to 60 km/h over 10 s, followed by a 3-s braking period to reach a complete stop (0 km/h) at the 13-s mark. The simulation then observes the fuel behavior within the tank for an additional 7 s while the vehicle remains stationary. Results reveal significant differences in fuel behavior between baffled and unbaffled tanks. In the absence of baffles, the sloshing motion is substantial, leading to a complete depletion of fuel in the intake port region for a duration of 3 s during both the acceleration and deceleration phases (between 10 and 13 s). Compared to a standard tank, the presence of baffles significantly reduced the sloshing amplitude by approximately 70%. Furthermore, baffles led to a 50% decrease in pressure variations on the tank walls. Temporary fuel starvation can negatively impact engine performance and combustion efficiency. Conversely, the presence of baffles within the tank effectively mitigates sloshing and ensures continuous fuel presence at the intake port the entire simulation. This suggests that baffles play a crucial role in maintaining a stable and consistent fuel supply to the engine, even during dynamic vehicle maneuvers. [ABSTRACT FROM AUTHOR]

In contemporary times, Helical tube heat exchangers (HTHXs) have gained significant prominence in energy-related sectors, frequently finding application in industrial and technical settings. Their impact on overall system efficiency and size is substantial. A comprehensive review addressing passive heat transfer enhancement methods in HTHXs is notably absent. This paper justifies its significance by providing a recent and systematic review of available passive methods. The passive approach offers advantages such as the absence of external power requirements and lower operational costs compared to active methods.This paper differentiates active and passive approaches. Studies collectively indicate a noteworthy progression in heat transfer enhancement in HTHXs. The paper meticulously evaluates passive methods like fins, inserts, geometry modifications, and baffles. Both experimental and numerical studies focus on improving heat transfer in HTHXs. However, further exploration is necessary to understand the negative effects of pressure drop in tube-side flow. Papers covering trends in future research should also prioritize the development of geometric designs for HTHX surfaces, potentially incorporating materials coatings to enhance heat transfer further. The authors present insightful issues and ideas that they estimate deserving of additional investigation in subsequent research endeavors

Limited access to safe drinking water is a critical global issue, particularly in areas with inadequate infrastructure. Solar stills offer a promising alternative for such regions. This study investigates the influence of square baffles within a modified solar still design on its overall efficiency. Additionally, the integration of reflectors is explored to enhance both evaporation and condensation rates. Furthermore, the effectiveness of a paraffin wax phase change material (PCM) combined with silver nanoparticles is assessed within the modified still. Thermo-economic analyses are conducted to evaluate the economic feasibility of the proposed system. The findings demonstrate a significant improvement in distillation yield. The modified still with square baffles achieved a yield of 9800 mL/m2.day compared to 3550 mL/m2.day for the reference still, representing a 193 % increase. Moreover, incorporating the nano-PCM at an optimal configuration (25 cords) resulted in a further 265 % productivity increase for the modified still with both square baffles and reflectors. This configuration also achieved an efficiency of 63 %. Economic analysis revealed a minimal cost difference between the reference still (0.014 $/L) and the modified still with square baffles and nano-PCM (0.01 $/L). In terms of environmental impact, the modified still exhibited a lower annual CO2 emission of 28.8 tons.

Shell and multi-tube heat exchangers (SMTHX) are widely used in various industries such as power generation, chemical processing, and refrigeration due to their high efficiency and flexibility. Improving heat transfer within an SMTHX is critical for enhancing overall performance and efficiency. This study investigates the comparative effectiveness of using baffles versus spring wires to enhance heat transfer in SMTHXs. Both experimental and numerical analyses were conducted over a Reynolds number range of 8500–12500, focusing on key parameters such as the Nusselt number, pressure drop, and exergy efficiency. The experiments were performed with a variable cold water flow rate on the shell side and a constant flow rate on the tube side. The numerical model was validated against experimental results. The findings reveal that the Nusselt number increases to 62 with baffles and to 65.5 with spring inserts, representing improvements of 1.54 and 1.61 times, respectively, compared to a plain tube under identical conditions. While the pressure drop for baffles is significantly higher than for spring inserts, the springs show a pressure drop that is 87 % of that observed with baffles. Additionally, exergy efficiency is superior with spring inserts. These results demonstrate that spring inserts are more effective than segmental baffles in enhancing heat transfer in SMTHXs. The study provides valuable insights into the mechanisms of heat and fluid flow, supported by visualizations of velocity, temperature, and pressure contours and streamlines.

Abstract The impact of baffles on a convective heat transfer of a non-Newtonian fluid is experimentally studied within a square cavity. The non-Newtonian fluid is pumped into the cavity through the inlet and subsequently departs from the cavity via the outlet. Given the inherent non-linearity of the model, a numerical technique has been selected as the method for obtaining the outcomes. Primarily, the governing equations within the two-dimensional domain have been discretized using the finite element method. For approximating velocity and pressure, we have employed the reliable $${\mathbb{P}}_{2}$$ P 2 – $${\mathbb{P}}_{1}$$ P 1 finite element pair, while for temperature, we have opted for the quadratic basis. To enhance convergence speed and accuracy, we employ the powerful multigrid approach. This study investigates how key parameters like Richardson number (Ri), Reynolds number (Re), and baffle gap $${{\text{b}}}_{{\text{g}}}$$ b g influence heat transfer within a cavity comprising a non-Newtonian fluid. The baffle gap ( $${b}_{g}$$ b g ) has been systematically altered within the range of 0.2–0.6, and for this research, three distinct power law indices have been selected namely: 0.5, 1.0, and 1.5. The primary outcomes of the investigation are illustrated through velocity profiles, streamlines, and isotherm visualizations. Furthermore, the study includes the computation of the $${Nu}_{avg}$$ Nu avg (average Nusselt number) across a range of parameter values. As the Richardson number (Ri) increases, $${Nu}_{avg}$$ Nu avg also rises, indicating that an increase in Ri results in augmented average heat transfer. Making the space between the baffles wider makes heat flow more intense. This, in turn, heats up more fluid within the cavity.

Sorption is often conducted in stirred batch reactors without assessing the impact of mixing on yield and costs. Operating the mixing in the batch reactor at a state of complete suspension, i.e., at just suspended impeller speed, NJS, is a compromise between these conflicting goals. Therefore, copper sorption on NaX zeolite using a pitched blade turbine was conducted in both baffled and unbaffled batch reactors at NJS. Maintaining constant impeller to reactor diameter ratio (D/dT = 0.32), and impeller off-bottom clearance (C/H = 0.33), kinetic sorption experiments were performed. Besides kinetic sorption experiments and the kinetic analysis of data obtained, to gain insight into the hydrodynamic behaviour of the system, transient multiphase computational fluid dynamics simulations (CFD) were performed. The NJS speed is related to the particle settling speed, wherein a higher zeolite suspension mass concentration requires a greater NJS speed, resulting in increased energy consumption. The differences in NJS speeds for the investigated zeolite suspension mass concentrations were found to be insubstantial, and therefore, the increase in mixing intensity for the tested systems was not deemed significant. Regardless of the zeolite mass used, the values of NJS and PJS (mixing power consumption) were consistently higher in the unbaffled reactor. The hydrodynamic conditions employed were found to have no significant effect on the maximum amount of copper sorbed or process efficiency, but was significantly affected by zeolite mass. The kinetics were affected by both, and, generally, sorption occurred faster in the unbaffled reactor.

The hemispherical solar still (HSS) is a simple device used to desalinate saline water, but it has low productivity. This study aimed to enhance the evaporation rate of a hemispherical solar still (HSS) through several design modifications. The main innovation involved integrating an upper absorber with hanging wick cords, creating a modified system called the cords wick hemispherical solar still (CWHSS). Additionally, electric heaters powered by photovoltaic panels were incorporated to further boost performance, along with the introduction of squared baffles inside the CWHSS. Experimental results showed that the highest efficiency was achieved with the CWHSS incorporating baffles, heaters, and a condenser (CWHSS-B), leading to a 258 % increase in distillate output and a 66.5 % thermal efficiency. Under optimal conditions, the distillation rates were 4000 mL/m²/day for the HSS and 14,300 mL/m²/day for the CWHSS-B with heaters. Furthermore, the cost of water treatment was calculated at $0.022 per liter for the HSS and $0.016 per liter for the CWHSS-B, indicating significant cost benefits with the modified design.

This review examines advancements in cords wick technology for optimizing water depth in solar stills, a crucial factor in enhancing desalination efficiency. Shallow water depths generally lead to increased productivity, and cords wick technology effectively reduces energy waste by drawing only evaporated saline water, minimizing hot water loss. Various modifications, such as reflectors, fans, and baffles combined with nano-enhanced PCM, have significantly improved the performance of cords wick solar stills. Notably, incorporating cords, reflectors, a fan, and square baffles resulted in a 264 % increase in distillate production. Additionally, these enhancements offer environmental benefits, with reported annual CO₂ emissions reductions of approximately 28.71 tons and water treatment costs ranging from $0.01 to $0.0185 per liter. The insights provided here contribute to the ongoing research on maximizing desalination efficiency using cords wick technology in solar stills.

This study investigates the effects of baffles and various other design changes on a partially filled fuel tank subjected to high-velocity projectile impact. Modelling of the tank filled with water is done using ANSYS software. The Eulerian domain is used to analyse water, whereas the Lagrangian domain is used to assess the tank and bullet. The developed finite element model is verified with available results in the literature. The effect of design parameters like edge fillet, number of baffles, thickness of baffles, orientation of baffles, height of baffles, position of the projectile and projectile speed on the impact responses of the fuel tank is studied. From the analysis results, it could be observed that the edge fillet provided the minimum stress due to the lower stress concentration on the fuel tank, but it was not effective in decreasing the velocity of the projectile. Therefore, the baffles are introduced inside the fuel tanks, which are highly effective in reducing the velocity and generating huge stress on the tanks. The velocity and position of the projectiles are also varied to understand their effect on the fuel tank. [ABSTRACT FROM AUTHOR]

Mass transfer efficiency, heat transfer efficiency, and treatment capacity play important roles in the continuous flow chemical process. To enhance the continuous flow chemical process, a novel mixer with triangular-notched rectangular baffles structure was designed and optimized. The performance of mixers was characterized by a comprehensive computational fluid dynamics (CFD) method that couples heat and mass transfer. The results show that the optimized mixer has a maximum increase of 4.25 times in mixing efficiency and 83.8% in heat transfer compared with 10 mm mixer without baffles structure. Furthermore, the scale of the mixer with triangular-notched rectangular baffles structures was enlarged to 25 mm under the premise of ensuring high mass and heat transfer efficiency, low-pressure drop and high treatment capacity. This study provides a scale-up strategy for continuous flow chemical process enhancement. [ABSTRACT FROM AUTHOR]

Sorption is often conducted in stirred batch reactors without assessing the impact of mixing on yield and costs. Operating the mixing in the batch reactor at a state of complete suspension, i.e., at just suspended impeller speed, NJS, is a compromise between these conflicting goals. Therefore, copper sorption on NaX zeolite using a pitched blade turbine was conducted in both baffled and unbaffled batch reactors at NJS. Maintaining constant impeller to reactor diameter ratio (D/dT = 0.32), and impeller off-bottom clearance (C/H = 0.33), kinetic sorption experiments were performed. Besides kinetic sorption experiments and the kinetic analysis of data obtained, to gain insight into the hydrodynamic behaviour of the system, transient multiphase computational fluid dynamics simulations (CFD) were performed. The NJS speed is related to the particle settling speed, wherein a higher zeolite suspension mass concentration requires a greater NJS speed, resulting in increased energy consumption. The differences in NJS speeds for the investigated zeolite suspension mass concentrations were found to be insubstantial, and therefore, the increase in mixing intensity for the tested systems was not deemed significant. Regardless of the zeolite mass used, the values of NJS and PJS (mixing power consumption) were consistently higher in the unbaffled reactor. The hydrodynamic conditions employed were found to have no significant effect on the maximum amount of copper sorbed or process efficiency, but was significantly affected by zeolite mass. The kinetics were affected by both, and, generally, sorption occurred faster in the unbaffled reactor. [ABSTRACT FROM AUTHOR]

Numerical computation of aiding mixed convection and heat transfer characteristics in a channel with a baffled heated wall is carried out in this work. The equations of mass, momentum and energy, alongside the boundary conditions, are solved by the finite volume formulation using the open source OpenFOAM® code. Simulations are accomplished under different parameter combinations, including the Reynolds number, Grashof number, and baffle dimension. The results are presented in terms of streamlines, isotherm contours, Nusselt number, and friction factor. The results obtained revealed that the flow translates from steady to unsteady state at a relatively low value of Reynolds number. The unsteady flow behaviour contributes to improve heat transfer by disturbing the near-wall region. The augmentation of velocity and baffle dimension leads to a notable heat transfer enhancement; however, this enhancement is less sensitive to the heating intensity augmentation. [ABSTRACT FROM AUTHOR]

In this paper, two heated blocks and three flexible baffles that are alternately placed on the upper and bottom sides of a rectangular channel are used to replicate the transient heat and air movement. The novelty of this research is the use of flexible baffles to destruct the thermal boundary layer with maintaining little pressure drop, and thus reducing the required pumping capacity. The finite thickness blocks are subject to a constant heat flux, while the baffles are very thin and deforms depending on the strength of the flow of coolant (air). Finite element method with arbitrary Lagrangian–Eulerian approach is used for solving such deforming domain problem. The problem is inspected transiently by varying the dimensionless time (τ=0.0 to 10) and two salient parameters which are Reynolds number Re=10−500, and baffle elasticity parameter E=105−108. Results show that the flexibility feature of the baffles contributes not only in directing the coolant towards the hot blocks, but also contributes in reducing the skin friction and pressure drop through the channel. At Re=150, the skin friction and pressure drop of the flexible baffles are 13.2% and 16.5%, respectively lesser than the rigid baffles. The improvement of Nusselt number with flexibility parameter is marginal and within a limited low Reynolds number, where the maximal improvement is about 3.4% at Re=150.

The present numerical study reports the performance of a cooling system for solar photovoltaic panels (PV) using different nanofluids (Al2O3, CuO, and ZnO). A novel parallel flow channel with strategically placed baffles was analyzed to improve the heat transfer between the back of PV and the nanofluid. The nanoparticles' Brownian motion and the nanofluid temperature effect were considered. Computational fluid dynamics was used to simulate the interaction between the fluid in motion and panel materials. Various nanoparticle concentrations, Reynolds numbers (18–1800), and solar radiation values (200–1000 W/m2) were examined. The results showed that the nanofluid composed of CuO was the most effective, improving thermal efficiency by 5.67 % compared to pure water in the lowest Re range. A 10 % vol. concentration of Al2O3 reduced temperature by up to 15 % and increased electrical efficiency by 4 % when the Re varied from 18 to 42. However, increasing the Re number and having low solar radiation values decreased the contribution of the nanofluid. Additionally, using baffles in the flow channel improved electrical efficiency by 2 %.

According to Department of Fisheries and Oceans Canada, culverts and other stream crossings must be designed to ensure fish passage. The effects of ice processes on these fish passage designs have never been assessed. This study is the first to document ice processes on two different types of fish passage designs (streambed simulation and baffle). The results of a 2 year field monitoring campaign showed that the culvert simulating the streambed retains a natural ice regime, i.e., both freeze-up and break-up occurred concurrently with the rest of the stream, while multiple supercooling events were recorded under a thin ice cover. As for the culvert with baffles, it was observed that the ice cover formed earlier and stayed longer in the culvert, which can create a barrier for fish transiting through them. [ABSTRACT FROM AUTHOR]

In this work, we made a numerical simulation of heat transfer in a pipe of a flat plate solar collector using two forms of the absorber plate (simple, with baffles) in the presence of obstacles on the insulating plate. The flow is unsteady and laminar where the heat exchange between the absorber and working fluid takes place in useful area. The aim is to study the effects of mass flow and the number of baffles as well as their height on flow and heat transfer characteristics. Several CFD simulations were carried out in order to determine the influencing parameters allowing better performances of the collector and ensuring a good homogeneity of the temperature at the channel outlet. It is shown that when the number and height of baffles increase and the mass flow decreases the mean outlet temperature and the heat transfer rate between fluid and absorber plate are improved. [ABSTRACT FROM AUTHOR]

Microfluidic technology has garnered growing interest in diverse domains. The efficacy and precision of microfluidic devices are significantly influenced by micromixing processes. Micromixers, comprising microchannels designed to blend fluids within a confined space and limited flow pathway, constitute indispensable components of microfluidic systems. Among these components, the micromixer stands out as a critical element, tasked with achieving maximal mixing efficiency while imposing minimal pressure drop. This paper focusses on the numerical and experimental study the baffle-based split and recombine chamber (B-SARC) micromixers. The models of a curved wavy micromixer (without baffle) and the baffle-based split and recombine chamber (B-SARC) micromixers with three baffles such as square, triangular and teardrop shaped baffles been developed using COMSOL Multiphysics software. The mixing performance analysis has been carried out by studying the mixing index and pressure drop. The influence of baffle shapes i.e. square, triangular and teardrop shaped baffles of aspect ratio 1, 1.5 and 2 on mixing performance analysis has been investigated numerically, for widespread assortment of Reynolds numbers (Re) lies between 0.1 and 90. The polydimethylsiloxane (PDMS) baffle-based split and recombine chamber (B-SARC) micromixers have been fabricated. Further, the experimental analysis has been carried out. The experimental analysis for pressure drop as well as mixing index has been performed. A good agreement has been observed between experimental and computational results which leads to validation of the computational results. The results revel the role of diffusion at lower Reynolds numbers and the production of derivative flows owing to advection at higher Reynolds numbers within the considered range of Re. [ABSTRACT FROM AUTHOR]

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The shortage of safe drinking water is among the issues that the globe is experiencing more and more. One of the best options for remote locations lacking in civilian infrastructure is solar stills. The primary goal of the current study was to determine how using different designs of longitudinal and square baffles in the basin of the cords pyramid solar still (CPSS) affects its performance with and without silver nanoparticles. In addition, raising the levels of evaporation and condensation was achieved by introducing reflectors and vapor extraction with CPSS. Also, the thermo-enviro-economic analyses were tested to obtain the profitability of the proposed system. The results reported that the distillation of CPSS with lined baffles (CPSS-LB) and PSS was 9150 and 3500 mL m−2 day, correspondingly, with improvement of 162%. Moreover, the distillation of CPSS with square baffles (CPSS-SB) was 193% greater than PSS, with the aggregated distillation of CPSS-SB and PSS being 9800 and 3350 mL m−2 day, accordingly. Also, utilizing reflectors with CPSS-SB increased the output over the PSS by almost 233% (3600 mL m−2 day for PSS versus 12,000 mL m−2 day for CPSS-SB), while the fan and reflectors increased production of CPSS by roughly 257% (3550 mL m−2 day for PSS and 12,650 mL m−2 day for CPSS with fan and reflectors). Besides, the CPSS-SB with Ag increased productivity over PSS by 274% (3200 mL m−2 day for PSS vs 11,970 mL m−2 day for CPSS-SB with Ag). Moreover, with the use of Ag nanoparticles, the productivity increase of CPSS with reflectors and fan was 274%, with a thermal efficiency of approximately 68.8% at 25 cords, while with 35 cords, with the use of Ag nanoparticles, the productivity increase of CPSS with reflectors and fan was 282% (3100 mL m−2 day for PSS and 11,850 mL m−2 day for CPSS), with a thermal efficiency of approximately 70%. For PSS and CPSS-SB-Ag, the reported expenses of the treated water were 0.0141 and 0.01 $L−1, correspondingly. The environmental parameter of CPSS-SB-Ag was annual CO2 emissions of 28.7 tons. Additionally, the enviroeconomic parameter (Z′) for CPSS and CPSS-SB-Ag was 370 and 420 per year for 340 operating days and two decades, respectively. [ABSTRACT FROM AUTHOR]

A numerical investigation of a curved trapezoidal-corrugated channel with E-shaped baffles is conducted for thermal-hydraulic performance and flow behavior involving the use of single and hybrid nanofluids. This investigation introduces a unique integrated methodology for enhancing heat transfer efficiency by simultaneously combining geometric modifications and optimizing coolant utilization. To simulate turbulent, single-phase flow in three-dimensional corrugated channels, a computational model has been developed. The model considers a Reynolds number (Re) range of 5 × 103≤Re ≤ 35 × 103 and implies a uniform heat flux of 1000 W/m2. A commercial software, Ansys fluent was used in order to simulate the fluid flow by setting the inlet temperature at 300 K and velocity according to the Reynolds number. The continuity equation, momentum equation, and energy equations are discretized using a second-order upwind method. The equation's residual has been assigned a value of 1 × 106 for absolute criteria. The study evaluates the thermal-hydraulic performance of single nanofluids (Al2O3/water, CuO/water, SiO2/water) and hybrid nanofluids (Al2O3–Cu/water, TiO2–SiO2/EG-water) at varying volume fractions (1%≤φ ≤ 5%). Additionally, the investigation examines the effects of corrugations, baffles, and geometric parameter: blockage ratio (BR = 0.10, 0.15, 0.25). The findings demonstrate that the effects of baffles and corrugations can lead to the creation of vortex flow and greater turbulence, which can promote heat transfer enhancement. Various nanofluids demonstrated a significant rise in the Nusselt number, ranging from 35% to 60%, when compared to water in a curved corrugated channel. Additionally, a lower BR resulted in a smaller but still notable gain of 15%–19%. An effective heat exchanger that results in a significant energy dissipation is measured by the energy ratio (ER). The use of corrugated channels with narrow baffles has been found to consistently outperform smooth channels in terms of thermo-hydraulic parameters, leading to enhanced heat transfer. Using BR = 0.10 over 0.25 resulted in an increase in ΔP, HTC, and ER of 48.44%, 18.71%, and 45.86%, respectively. The implementation of a hybrid nanofluid consisting of 1% (20% TiO2-80% SiO2)/(60% Water-40% EG) volume fraction in a curved corrugated channel with baffles resulted in a significant improvement of 36.49% in thermal performance. This finding suggests that the aforementioned nanofluid composition and design parameter, characterized by a blockage ratio of 0.10, are the most effective in enhancing thermal performance.

Photocatalysis is an advanced oxidation process, which has been gaining attention as a sustainable technology for tackling pollution. Optimum design, fabrication and scaling up of novel photocatalytic reactors are faced with problems such as fabrication cost and numerous experimental trials for optimisation. Computational fluid dynamics (CFD), a computer simulation technique can ease the process of scaling up photocatalytic reactors. The current study focuses on CFD modelling of a serpentine flow path photocatalytic reactor with curved baffles for phenol degradation. The investigation compared different reactor configurations to finalise the optimum design with maximum removal efficiency. Initially, a simple cuboidal reactor was chosen with an efficiency of 27%. However, with a serpentine flow path being introduced, the reactor displayed an improved efficiency of 42%. The addition of baffles improved flow homogeneity and degradation efficiency. The investigation showed that serpentine flow increased the residence time and fluid mixing, while the curved baffles prevented flow channelisation, which enhanced the degradation efficiency. Efficiencies corresponding to different baffle types and geometry were also compared and the final reactor design chosen was a horizontal curved baffled serpentine flow reactor with a flow rate of 0.3 L/s and improved efficiency of 43.1% for a residence time of 18.44 s. HIGHLIGHTS Photocatalytic degradation of phenol on different reactor geometries was investigated.; Effect of serpentine flow path on photocatalytic degradation was studied using computational fluid dynamics.; The effect of baffles on fluid flow and pollutant degradation was investigated.; Optimum geometrical design for a serpentine flow baffled photocatalytic reactor for maximum photocatalytic degradation efficiency was obtained.;

Bu çalışmada farklı gözenek oranına sahip perdelerin çalkantıyı sönümleme etkisi sayısal olarak incelenmiştir. Sayısal modelde perdeler tankın her iki yanal yüzeyine yerleştirilmiş ve salınım hareketine zorlanmıştır. Perdeler için serbest su yüzeyinde, altında ve üstünde olarak üç farklı konum belirlenmiştir. Her bir perde için, serbest su yüksekliğinde okunan basınç değerleri ile akışkan serbest yüzey deformasyonu zamana bağlı olarak karşılaştırılmıştır. Çalışma sonucunda tank yanal yüzeylerine uygulanan perdelerin, yüzey deformasyonunu azaltarak serbest su seviyesinde çalkantı kuvvetlerini düşürdüğü gösterilmiştir. Perdelerin basınç sönümleme oranları karşılaştırıldığında, en iyi oranın gözeneksiz perde olduğu belirtilerek. Serbest su yüzeyine yakın perde yerleşiminin basınç sönümlemede daha etkili olduğu tespit edilmiştir. Ancak gözenekli perdelerin sönüm oranı katı perdeye yakın olduğu, tanka daha az yük getireceği için bu tip perdenin uygunluğu vurgulanmıştır.

The purpose of the present study is to examine the influence of baffles presence at downstream system on weir gate hydraulic response. Two baffles configuration (triangle and angle shapes) are installed in bed flume. Two different spacing are used between the baffles and two different directions for baffles are also adopted. The study tries to investigate the variation in upstream Froude number, downstream Froude number, Reynolds number, actual discharge, discharge coefficient, downstream average water depth and the hydraulic system efficiency which is expressed as function of downstream water depth. It has been shown that the number of baffles has a direct and significant impact on flow hydraulic characteristics of weir-gate structure regardless of the spacing between baffles and the direction of baffles related to flow. Baffles number and spacing have essential impact on the water flow velocity of system and this impact leads to increase the flow resistance. The results clarify that the upstream Froude number, downstream Froude number, Reynolds number, actual discharge and discharge coefficient are decreased with the increase in baffles number except the average downstream water depth which increases with increase in baffles number. The efficiency of hydraulic system gives a good indicator for using baffles with weir-gate structure. At the end this paper shows a fruitful result of efficiency. This experiment run condense on the baffle’s numbers and directions with respect to the water flow direction at the downstream regime. So, the rises in the water level relies on the numbers and directions of the baffles as compare to the case without using baffles at the flume downstream region. The actual discharge and weir-gate discharge coefficient are more sensitive to the increase in the baffles’ numbers and the baffles direction with respect to the water flow direction. [ABSTRACT FROM AUTHOR]

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Especially in small communities, little attention is paid to the hydraulic characteristics of wastewater treatment systems. Motivated by this problem, and using the ANSYS fluid dynamics software, the hydrodynamic evaluation of the residual water flow in a rural plant maturation pond was carried out. For the stationary modeling of the velocity and turbulence fields, the standard k-e model was used; and for transient modeling of virtual tracer transport, the species transport model without chemical reaction was used. Subsequently, the analysis of the distribution of retention times was carried out, in order to obtain the flow patterns that govern the hydrodynamics of the pond. The results revealed the presence of hydraulic short circuits, stagnant zones, and recirculations, due to design deficiencies and operating conditions over the years. Given this situation, and by bibliographic recommendation, new modified geometries were proposed with longitudinal and transverse baffles at 70 and 90% in relation to the width and length of the pond. As a result, the hydraulic characteristics improved notably in all cases; however, the models configured at 90% achieved higher efficiency. [ABSTRACT FROM AUTHOR]

The effects of speed, number of baffles and baffle lengths of a developed tumble drum mixer as they relate to the degree of mixing of feed in the mixer were investigated. Results showed that the degree of mixing of the tumble drum mixer was influenced by the linear effects of the number of baffles, also the interactions of the number of baffles and baffle lengths of the mixer at 5% probability. These factors accounted for about 94.37% of the variations in the degree of mixing of the mixer. The highest degree of mixing of 79.21% was obtained when the number of baffles were 9 and baffle length was 20cm. [ABSTRACT FROM AUTHOR]

It has been identified that temperature polarization and concentration polarization are typical near-surface phenomena limiting the performance of membrane distillation. The module design should allow for effective flow, reducing the polarization effects near the membrane surfaces and avoiding high hydrostatic pressure drops across and along the membrane surfaces. A potential route to enhancing the membrane distillation performance is geometry modification on the flow channel by employing baffles as vortex generators, reducing the polarization effects. In this work, various baffles with different structures were fabricated by 3D printing and attached to the feed flow channel shell in an air gap membrane distillation module. The hydrodynamic characteristics of the modified flow channels were systematically investigated via computational fluid dynamics simulations with various conditions. The membrane distillation tests show that adding the baffles to the feed channel can effectively increase the transmembrane flux. The transmembrane flux with rectangular baffles and shield-shaped baffles increases by 21.8% and 28.1% at the feed temperature of 70 °C. Moreover, the shield-shaped baffles in the flow channel not only enhance the transmembrane flux but also maintain a low-pressure drop, making it even more significant. [ABSTRACT FROM AUTHOR]

This paper explores the heat transfer by mixed convection within double lid-driven enclosures filled with Cu–Al 2 O 3 hybrid nanofluids. The domain contains T-shaped baffles and is filled with local thermal non-equilibrium (LTNE) porous medium. The wavy boundaries are partially cooled, while the inner baffles have constant heat flux conditions. Mathematical formulations for the system irreversibility in cases of LTNE, constant heat flux conditions and double diffusive are presented and analyzed. The solution methodology is depending on the finite volume scheme in case of non-orthogonal grids. The major results revealed that the alteration of the undulation number λ from 1 to 5 gives an augmentation in values of θ f,max up to 4.57%. Also, the increase in the lengths of the baffles causes a reduction in the flow, while θ f,max is rising. Furthermore, the alteration in Ri from 0.5 to 10 gives an augmentation in θ f,max up to 12.97%. [ABSTRACT FROM AUTHOR]

Resource-efficient buildings are one of the most important challenges of the construction industry, which could be achieved by limiting the extraction of natural resources and by replacing them with industrial residues. The present work proposes innovative panels made from textile wastes as an efficient solution for making the semi-open atrium in the Polytechnic University of Bari, acoustically suitable for use as an area of study. Several measurements were carried out in the atrium under empty and occupied conditions in order to characterize the sound field of the space (i.e., the reverberation time and the sound pressure level) and the actual sound sources (i.e., the sound power level of the students occupying the space). The on-site measurement results were useful to calibrate a geometrical acoustic model implemented in CATT-Acoustic software and used to predict the effect of the proposed treatments. About 700 m2 of absorbent panels were distributed, leading to a predicted reduction in the reverberation time from 2.4 s to 1.4 s at 500 Hz, and consequently to an estimated 3 dB reduction in sound pressure level, resulting in a reduction in the background noise level due to speech. Furthermore, as a consequence of the “Lombard effect”, a decrease in the background noise level will likely reduce the sound power level of the speakers by 2 dB, with an expected overall reduction of 5 dB.

Additive manufacturing has the potential to unlock a large degree of geometric freedom in the shaping of catalytic material, thereby providing new possibilities to optimize catalyst holdup, pressure drop and heat and mass transfer characteristics. In this modelling study, baffled logpile structures are proposed as a promising candidate to exploit this potential, by shaping the catalytic material as a static mixer, generating cross-flow. An OpenFOAM Computational Fluid Dynamics study was performed on various 2D structure designs to map the trade-off between heat transfer, pressure drop and residence time distribution as a function of the design, length and gap spacing of the baffle. It is observed that structures with the longest baffles provide optimal heat transfer performance, and that the baffle gap spacing can be used to tailor the trade-off between heat transfer and pressure drop. In comparison to a packed bed filled with spherical particles, the novel structures offer a heat transfer rate four to six times as high at the same pressure drop. Whilst full 3D simulations, validated by experiments, remain to complete the analysis, the current work illustrates the potential of this novel class of structured catalyst materials for intensified chemical reactors. [Display omitted] • The hydrodynamics and heat and mass transfer properties of 3D printed baffled logpile catalyst structures were studied. • The novel geometries provide a more lenient heat transfer – pressure drop trade-off compared to standard logpile structures. • Optimized designs outperform the packed bed of spheres, requiring less pressure drop to achieve the same heat transfer rate. [ABSTRACT FROM AUTHOR]

This work aims to study the different characteristics of Newtonian fluid flow and heat transfer through a 1:3 sudden expansion channel with or without plane baffles using the finite volume method. The flow is assumed viscous, incompressible, steady, and laminar. The different characteristics of hydro-thermal fluid flow phenomena have been studied for Re ε [0.1 - 200] to demonstrate the influence of the presence of baffles. The profiles of velocity, pressure, skin friction coefficient, friction factor, average Nusselt number, and pumping power have been examined for both the cases of the presence and absence of baffles. It has been observed that the hydro-thermal characteristics become more pronounced with the increase in the number of baffles. In the case of three baffles of equal length, at Re = 200 it is calculated that if the thickness of the baffles is same and equal to 10% of the length, then the value of Nuav becomes approximately 1.2 times of that in the absence of baffle. For the same value of Re, it has been found that for the presence of one baffle of length equal to the width of the inlet section of the channel and of thickness 10% of the same, the value of Nuav becomes 1.11 times of that in the absence of baffle, while in the case of three baffles of equal length and of equal thickness like the above mentioned case of one baffle, the value of Nuav becomes 1.25 times of that in absence of baffle. It has also been revealed that the enhancement of thermal phenomena increases with the increase in the baffle’s height. [ABSTRACT FROM AUTHOR]

Microcarrier suspension performance and ensemble-averaged flow fields at the just-suspended condition are studied in a scale-down mimic of the Allegro STR single-use bioreactor range (abbreviated A-STR) and compared to an equivalent standard cylindrical configuration (abbreviated S-STR). Four commercial microcarriers were assessed to determine the required impeller agitation rate and corresponding power input per unit volume to achieve suspension – Cytodex™ 1, Cytodex™ 3, Cytopore™ 1, and Hillex® II microcarriers. The A-STR operating in down-pumping mode (DP) achieved homogenous microcarrier suspension at considerably lower power input when compared to the other baffled configurations. For the A-STR (DP), the power input per unit volume demand was 67.8 % lower than the A-STR in up-pumping mode (UP), 77% lower than the S-STR (DP) and 66.8 % lower than the S-STR (UP). Flow structures investigated at the just-suspended condition, in the transitional regime, were in line with those previously presented in the turbulent regime at considerably higher Reynolds number. This indicates that the normalised flow structures presented in this work are representative of those in the commercial Allegro STR range, despite operating at significantly reduced scale and Reynolds number. Removal of baffles resulted in substantially reduced power input required to achieve homogenous suspension in all configurations – other than the A-STR (DP), which exhibited relatively similar performance to the corresponding baffled configuration. Considering adherent cell sensitivity and mixing implications, and based on the results found in this work, the baffled A-STR (DP) is recommended for achieving microcarrier suspension at the lowest specific power input. • Microcarrier suspension is characterised in a scale-down mimic of the Allegro STR. • Homogenous suspension can be achieved at reduced power input in the cubical geometry. • The implications of baffles on suspension efficiency are explored. [ABSTRACT FROM AUTHOR]

This work aims to enhance the performance of a solar air heater (SAH) by introducing broken V-ribs as roughness elements on the absorber plate. The unit with a conventional flat absorber plate is referred to as the "FSAH," while the unit with a broken V-rib-shaped absorber plate is called the "VSAH." The experiment was performed for three air velocities: 25 m/s, 20 m/s, and 15 m/s and the corresponding air flow rates were 0.037 kg/s, 0.031 kg/s, and 0.023 kg/s, respectively. The results showed that the maximum temperature was experienced on the absorber plate, followed by the glass plate for both SAHs. Overall, the average absorber and glass plate temperatures of the VSAH were 0.6–1.4 °C and 0.4–1.9 °C lower than those of the FSAH. Compared to the FSAH, the experimental results showed that the VSAH experienced useful power and thermal efficiency that were 16.6–19.8% and 15.7–20.4% higher, respectively, while the top surface heat losses were found to decrease by 2.1–8.1%. Due to the disrupted air paths in the VSAH, the observed pressure drop was 113.3–133.3% higher than that of the FSAH. More impotently, the thermo-hydraulic performance factor was always higher 1 and the observed values were 1.48, 1.39, and 1.24 at the va (velocity) values of 15, 20, and 25 m/s, respectively. Therefore, the proposed VSAH had an admirable thermal performance as compared to FSAH. Further, optimization through varying the roughness parameters, namely, relative blockage width (W/w), relative pitch ratio (P/e), number of baffles (n), relative blockage height (e/H), and angle of attack (β) could helped to achieve better performance. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)