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Densification techniques allow biomass to be used in the energy mix with coal or as a direct replacement for coal as it is a renewable resource. Typically, biomass is bulky, so thermochemical methods, like torrefaction, reduce volatiles and moisture, leaving a higher composition of fixed carbon. After the torrefaction process, the torrefied biomass poses problems during handling, transportation, and storage because it consists of small (

The present study numerically investigates the two-dimensional steady incompressible turbulent flow characteristics in an enclosed cavity. The finite volume method (FVM) is used to discretize the governing equations, and k-ε turbulence models are adopted to predict the flow characteristics. The turbulent flow behavior is studied by varying the speed ratio (0.05 ≤ S ≤ 1.0), aspect ratio (0.5 ≤ K ≤ 2.0), and Reynolds number (1 × 104 ≤ Re ≤ 2 × 105). The flow characteristics are analyzed using stream function (ψ), Reynolds stresses (u'v'), and turbulent quantities. Results show the Reynolds number and speed ratio significantly influence the formation of vortices over the selected range of operating parameters. With the speed ratio, the turbulent kinetic energy reduces considerably by increasing the Reynolds number and aspect ratio. Similarly, for S = 0.05 and K = 0.5, the turbulent kinetic energy and dissipation rate are decreased by 89.16% and 42.28%, respectively. When Re is increased from 1 × 104 to 2 × 105, the turbulent viscosity increases by 92.10%. By comparing the results, average turbulent quantities are decreased by increasing the flow parameters. • Turbulent flow behavior is investigated by using the FVM near-wall treatment approach.One of the unique parameters called speed ratio is emphasized. • Contours of turbulence kinetic energy, dissipation, and viscosity are examined. • The average intensity of turbulent quantities is decreased by increasing the speed ratio.

This paper deals with the topic of reducing drag force acting on aircraft wings by incorporating novel winglet designs, such as multi-tip, bird-type, and twisted. The high-speed NASA common research model (CRM) was selected as the baseline model, and winglet designs were retrofitted while keeping the projected wingspan constant. Computational analysis was performed using RANS coupled with the Spalart–Allmaras turbulence model to determine aerodynamic coefficients, such as CL and CD. It was observed that the multi-tip and bird-type designs performed exceptionally well at a low angle of attack (0°). A parametric study was conducted on multi-tip winglets by tweaking the parameters such as sweep angle (Λ), tip twist (Є), taper ratio (λ), and cant angle (Φ). The best combination of parameters for optimal aerodynamic performance while maintaining the wing root bending moment was determined using both the Taguchi method and Taguchi-based grey relational analysis (T-GRA) coupled with principal component analysis (PCA). Also, the percentage contribution of each parameter was determined by using the analysis of variance (ANOVA) method. At the design point, the optimized winglet design outperformed the baseline design by 18.29% in the Taguchi method and by 20.77% in the T-GRA coupled with the PCA method based on aerodynamic efficiency and wing root bending moment.

Magnetohydrodynamic application in the biomedical field made the researcher work more on this field in recent years. The major application of this concept is in scanning using laser beams, delivering a drug to the targeted points, cancer treatment, enhancing image contrast, etc. These applications are depending on the flow and heat transfer properties of the magnetic conducting fluid and on the geometry of the flow field. An increase in the demand for the miniature in the shape and size of the clinical devices attracts the researcher to work more on design optimization. In this study optimization of magnetic field strength, geometry of domain, Prandtl number, Reynolds number for a steady, incompressible double-diffusive flow is performed using Taguchi and Analysis of variance technique. Linear regression model is used to predict the average Nusselt and Sherwood numbers. Numerical simulations were performed using finite volume method (FVM) based numerical techniques. Experiments are designed based on Taguchi orthogonal array and FVM based numerical codes were used to obtain the results. Results show that an increase in the aspect ratio from to 0.5 to 2.0 improves the heat transfer rate by 62.0% and the mass transfer rate by 38.5%. As the Prandtl number increases from 0.7 to 13.0, heat transfer rate increases by 80.0% and mass transfer by 75.0%. This specific study could be applied in designing of solar ponds and to investigate heat and mass transfer effects during cancer treatments.

This research incorporated nano TiO2 and ZrO2 particles into the NiP electroless bath to produce NiP-TiO2-ZrO2 composite deposits on magnesium AZ91D substrates. The impact of sodium dodecyl sulfate (SDS) (anionic surfactant) was utilized for deposition to minimize the agglomeration and clustering of particles in the electroless bath. Surface properties such as atomic force microscopy, energy dispersive X-Ray analysis, scanning electron microscopy, and X-ray diffraction are used to evaluate the surface morphologies of coating, surface roughness, elementary composition, and crystalline structure of the deposits. Furthermore, the impact of SDS surfactant on the corrosion properties of deposits was also studied using potentiodynamic polarization in a 5 wt% NaCl solution. The overall results reveal that incorporating anionic surfactant SDS at the optimum concentration of 1.5 g/L (CMC value) improved wettability, deposition rate, and surface roughness compared to the deposits developed without surfactant. The proposed mechanism is that the molecules of SDS surfactant could come into contact with the surface of NiP-TiO2-ZrO2 composite coating in the bath, increasing nanoparticle dispersion and resulting in a uniform coating. Furthermore, the electrochemical results show improved corrosion protection efficiency (PE%) of NiP-TiO2-ZrO2 composite coatings by increasing the concentration of SDS surfactant, achieving ∼87.9% at (1.5 g/L) CMC value.

A possible method for fluid transportation of heavy oil through horizontal pipes is core annular flow (CAF), which is water-lubricated. In this study, a large eddy simulation (LES) and a sub-grid-scale (SGS) model are used to examine CAF. The behavior of heavy oil flow through turbulent CAF in horizontal pipes is numerically investigated. The Smagorinsky model is utilized to capture small-scale unstable turbulent flows. The transient flow of oil and water is first separated under the behavior of the core fluid. Two different conditions of the horizontal pipes, one with sudden expansion and the other with sudden contraction, are considered in the geometry to investigate the effects of different velocities of oil and water on the velocity distribution, pressure drop, and volume fraction. The model was created to predict the losses that occur due to fouling and wall friction. According to the model, increasing water flow can reduce fouling. Additionally, the water phase had an impact on the CAF’s behavior and pressure drop. Also, the increased stability in the CAF reduces the pressure drop to a level that is comparable to water flow. This study demonstrated that a very viscous fluid may be conveyed efficiently utilizing the CAF method.

Building cooling and heating, solar-powered energy production, energy recovery, and other energy-consuming industries have all seen an increase in the use of cold/hot latent thermal energy storage (LH-TES). Through energy recovery, LH-TES that uses phase-change materials (PCMs) as a storage medium helps to close the energy supply and demand gap and raises the possibility of energy savings. However, the stability, thermal, physical, and chemical properties of the PCM play a major role in how effectively it can be used. In recent years, adding gelling and thickening agents (GTAs) has gained popularity apart from the nanoparticles (NPs) and nucleating triggers (NTs), particularly for the creation of stable PCMs. Therefore, the current work’s goal is to provide an overview of how GTAs are used in the process of developing reliable PCMs for TES applications. It has been found that using GTAs not only increased stability but also decreased sedimentation, leakage, and the supercooling degree (SCD). It was noted that the addition of a GTA with a weight percentage of 2–15% resulted in excellent stability with a negligible leakage rate and latent heat reduced by 3.6–35% after only 200 cycles. Furthermore, PCMs for solar-thermal and building heating systems in the medium-temperature range (21–61 °C) were mostly studied for their performance with GTAs, but no study for a cool TES application was reported. Most works have studied inorganic PCM components with GTAs, and a few reports are available for paraffin. However, the GTA blending resulted in reduced thermal performance due to a decrease in thermal conductivity, latent heat, and a rise in viscosity. Further, NTs and NPs with small amounts were seeded into the PCM-GTA for eradicating the SCD with enhanced TC and accelerated energy transfer.

Background & objectives: Vector ecology and taxonomy of snails is a prerequisite for controlling schistosomiasis in the tropics. The ecology of the freshwater limpet genus Ferrissia was investigated for detection of cercariae larvae in them, and taxonomic description of a new species of the genus Ferrissia. Methods: This study was conducted in 15 perennial streams from five different hills of south India. To study the seasonal patterns, a stream from each hill was selected and sampled in three seasons. In each study site, triplicate sampling was done and specimens were collected from stream substrates as well as waste material submerged in stream. Microscopic examination was carried out for detecting cercariae larvae in limpets. Results: Three freshwater limpets (F. tenuis, F. verruca and F. fivefallsiensis) were observed. Seasonality influenced the abundance of limpets. The highest abundance was observed during post-monsoon (December and January). The distribution of Ferrissia was observed at riffle in pebbles, leaf litter and wastes (polyethylene bags and snacks cover) submerged in water. No cercariae larvae were found from the body of limpets. In this study, we described a new species of Ferrissia fivefallsiensis. Interpretation & conclusion: Our results showed the distribution, habitat preference and seasonality of limpets, and recommend the detection of Schistosoma from limpets as well as human samples by use of molecular tools.

The study assessed Trichoderma spp. as a biocontrol agent for managing wilt-nematode complex in tomato crops, aiming to mitigate yield losses. Fusarium sp. and Meloidogyne sp. were isolated from infected plant samples and confirmed molecularly and morphologically as Fusarium oxysporum f.sp. lycopersici and Meloidogyne incognita. Four Trichoderma spp. procured from the Department of Plant Pathology, Tamil Nadu Agricultural University, India were identified molecularly as Trichoderma asperellum (Tv1), Trichoderma asperelloides (Tasd1), Trichoderma harzianum (Th1), and Trichoderma koningiopsis (Tk1) utilizing ITS and TEF1 primer pairs. Among them, Tv1 effectively inhibited the mycelial growth of pathogen isolates. Furthermore, crude metabolite of Tv1 exhibited similar effects. The mortality rate of M. incognita J2s ranged from 90.48% to 100% after 24-72 h of incubation and inhibition percentage of egg hatching reached 90.20%. The shoot length, root length, fresh weight, and dry weight of the tomato plants treated with Tv1 conidia were increased. In a pot experiment, Tv1 treatment reduced disease incidence by 64.57%, comparable to carbendazim treatment (82.32%). Tv1-treated plants had fewer root galls, egg masses, and J2s per 100 g of roots than the inoculated-untreated control plants. The root-knot index (RKI) was significantly lower in plants treated with carbafuran (1.98 ± 0.047) and Tv1 (3.06 ± 0.086) than in control (4.47 ± 0.109). The bio-control efficiency of Tv1 against M. incognita was 21.04%, and the nematodes' reproductive factor (RF) declined to 0.53 in Tv1 treatment group. Based on the findings above, it was established that Tv1 effectively controlled nematode populations and wilt disease when applied in soil., (© 2024 Wiley‐VCH GmbH.)