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The study presents the quantitative effect of the recorded failure and repair data on the performance of a liquid milk processing plant in terms of its availability and reduced capacity. Process modeling and behavioral analysis of the system has been carried out by dividing the system into four subsystems placed in series using Petri Nets approach. A licensed software package (named Petri module of GRIF) has been used for model formalism and its simulation. The results of this study are expected to be useful to the proprietors of the milk processing plant as well as for practitioners from other fields such as multiprocessor electronic systems, telecommunication systems and production systems among others who want to analyze, understand and predict the behavior of various types of equipments. Reliability, Availability, and Maintainability modeling tools described here can be of helpful to them in planning selective maintenance strategies for their systems.

This research presents a numerical study on heat transfer and flow characteristics for two pipe fitted by two different dimpled spiral center plate by utilizing Al2O3, CuO and TiO2 nanofluids as cooling fluids. Considering the effect of dimples arrangement, nanoparticle diameter dp, nanofluids volume fraction φ and also the heat transfer coefficient, thermal property. Average amount of entropy generation Sa and maximum local temperature of wall Tmax were discussed. Results demonstrate that the in-line arrangement geometry behaves better in compare to the geometry with the staggered arrangement. 47.3% is the maximum enhancement of convection heat transfer for the in-line arrangement in compare with the smooth spiral central plate with base flow. Using nanofluids improved the wall temperature distribution, and using nanofluid caused great improvement in thermal conductivity with a little raise in dynamic viscosity. Using nanofluids caused a considerable decrease in Sa, which also as the result of rising φ, and Sa maximum reduction is about 24.7%. Tmax considerably declines by using nanofluids and enhanced by a rising φ. Also, CuO–water nanofluid has a better effect on heat transfer and flow characteristics than the other nanofluids.

A class of 2D metamaterials with sign-switching coefficients of thermal, pressure and moisture expansions is proposed herein—such materials not only change properties with environmental changes, but also reverses between positive and negative. Designed from bimaterial strips and arranged into the form of square grids, changes to environmental conditions transform the square grids into 2D array of 8-pointed stars found in Islamic art and architecture. Results indicate that the bimaterial strip deflection can fit the 8-pointed star when the overall strain is $$-0.105$$ . Suppose the general expansion coefficients for both materials in the bimaterial strip $$({\alpha }_{1},{\alpha }_{2})$$ are known, then the required environmental changes for attaining the 8-pointed star array can be determined. The currently proposed metamaterial not only demonstrates its capability of attaining properties with reversible sign, but also achieve aesthetic feature with historical significance.

Magneto-hydrodynamic double-diffusive natural convection in a cavity is numerically investigated in the present work. Al2O3, Cu, and Ag based nanofluids in a square cavity with a thermal and solute source in the center, and uniform magnetic field are considered. The Patel model is employed to estimate the thermal conductivity of applied nanofluids, and the numerical calculation is based on the implementation of the lattice Boltzmann method and utilizing the standard $$D_{2} Q_{9}$$ model to study the heat transfer, and also species concentration. A parametric study is carried out to observe the influence of the type, the volume fraction of nanoparticle ( $$\phi = 0 - 5\%$$ ), Rayleigh ( $$Ra = 10^{4} - 10^{5} - 10^{6} )$$ , Lewis $$\left( {0.1 - 2 - 10} \right)$$ , and Hartmann number $$\left( {10 - 20 - 100} \right)$$ on average Nusselt and Sherwood numbers, flow fields, temperature, and concentration distribution. The results show that an augment in nanoparticle volume fraction and Rayleigh number increased the average Nusselt and Sherwood numbers. Lewis number showed a significant impact on mass transfer rate. However, it did not affect the heat transfer rate remarkably. Applying a magnetic field caused a reduction in flow circulation which resulted in a decline in heat and mass transfer. A comparison of the simulation outcome with the available data shows that the generated code perfectly captures the fluid flow behavior and heat transfer process as a function of the affecting parameters.

In this study, the effects of sodium caseinate (NaCN; emulsifier) concentration, a type of hydrophilic emulsifier, as well as concentration of primary W/O emulsion on the stability of water–oil-water (W/O/W) emulsions were investigated. Emulsions were made using two different emulsification techniques including ultrasonic liquid processing and high pressure homogenization (HPH). Microscopy images of W/O/W emulsions in combination with droplet size analysis and viscosity measurements showed that the sample with a higher percentage of primary W/O emulsion (50 wt% vs. 40 wt% and 25 wt%) was more resistant to coalescence (narrower droplet size distribution and lower creaming index). The higher stability of this emulsion at 50 wt% is due to the enhancement in the solution viscosity which slows down the coalescence and destabilization kinetics. The increase in the NaCN concentration from 0.3 wt% to 0.9 wt% (based on total weight of emulsion) led to formation of larger droplets possibly due to the destabilization of primary W/O emulsion through the disruption of polyglycerol polyricinoleate (PGPR) layer. Regarding the effect of emulsifier type, incorporation of Cremophor EL and Tween 60 in comparison with NaCN resulted in formation of smaller droplet size due to their enhanced surface activity at the interface. Finally, we found that using high pressure homogenizer (HPH) instead of ultrasonic processor was detrimental to the emulsion stability and size distribution. These findings further provide new pathways to design emulsion systems for food and drug delivery applications.