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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 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.