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High temperature and humidity of many reason of India in the summer season is the major challenge for human comfort also in the drying. In the present work, experiments have been performed to examine the cooling and dehumidification process in the summer season for human comfort and industrial application with the help of calcium chloride (CaCl2) based desiccant material solid desiccant wheel integrated with solar heating arrangements. In this study experimental findings are also evaluated by the mathematical model. During the dehumidification of air in the process unit humidity changes from 17.75 to 29.03 g H2O/kg dry air to 2.8–3.9, 6.8–8.15, 8.92–10.9 & 9.79–11.87 g H2O/kg dry air for flow rate at 1, 2, 3 & 4 m/s, respectively. The process air outlet temperature is increased in the range of 2.58–3.53 K for all air flow rates. After humidification of process outlet air, human comfort condition (HCC) is produced with temperature and humidity in the range of 30–33 °C and 7.77–12.47 g H2O/kg dry air for different air flow rates. Overall airflow for velocity 2–4 m/s can be recommended for the HCC condition. The proposed modelled expression indicates less than 10 % error between the actual and modelled value for different sections. [ABSTRACT FROM AUTHOR]

A methodology based on sound non-equilibrium thermodynamics principles is developed to estimate the extremum dissipation point for steady-state incompressible flow past a sphere at low Reynolds numbers. It is shown, that the extremum dissipation point appears at the point when both the shear stress and the pressure at the surface of the sphere are equal to zero. The Reynolds number and the position of the extremum dissipation flow past a sphere were further estimated with the aid of a mathematical model for pressure distribution on the sphere surface, accounting for both creeping and ideal flow. The parameters of the model were determined by comparison of the calculated pressure distribution at the surface with the available literature data. The conditions at which the separation angle and the extremum dissipation angle coincide were also investigated. It is believed that this work could be used to further elucidate the flow past a sphere. [ABSTRACT FROM AUTHOR]

Slurry polymerization processes using Zeigler–Natta catalysts are most widely used for the production of polyethylene due to their several advantages over other processes. Optimal operating conditions are required to obtain the maximum productivity of the polymer at minimal cost while ensuring operational safety in the slurry phase ethylene polymerization reactors. The main focus of this multi-objective optimization study is to obtain the optimal operating conditions corresponding to the maximization of productivity and yield at a minimal operating cost. The tuned reactor model has been optimized. The single objective optimization (SOO) and multi-objective optimization (MOO) problems are solved using non-dominating sorting genetic algorithm-II (NSGA-II). A complete range of Pareto optimal solutions are obtained to obtain the maximum productivity and polymer yield at different input costs. [ABSTRACT FROM AUTHOR]

This document is a preface to a special issue of the International Journal of Chemical Reactor Engineering (IJCRE) dedicated to the "International Conference on Energy Sustainability and Advanced Materials - 2022 (ICESAM-2022)" held at UPES, Dehradun, India. The conference brought together renowned academicians and industrialists from around the world to discuss topics related to energy security, sustainability, and advanced materials for energy applications. The special issue includes peer-reviewed manuscripts derived from oral presentations at the conference, covering a wide range of topics in energy and chemical engineering. The document expresses appreciation for the contributions of the speakers, reviewers, and authors, and looks forward to future collaborations with IJCRE. [Extracted from the article]

The supercritical antisolvent (SAS) recrystallization process is one of the most promising recrystallization techniques for the particle formation of pharmaceutical compounds. In this process, a solution of active pharmaceutical ingredient (API) is sprayed into the supercritical carbon dioxide (SC CO2) environment. The mass transport of both the solvent and the antisolvent results in supersaturation followed by the crystallization of the API. In this work, a model is developed to estimate the supersaturation profile of solute in a droplet falling in the SC CO2 environment. The droplet consists of paracetamol as a solute and ethanol as a solvent. It moves down in the antisolvent (supercritical CO2) environment. Interestingly, the present model predicts a rise in supersaturation followed by a fall for a while and then a sharp increase. The competing phenomena of nucleation and growth mechanisms are used to justify this variation in the supersaturation. [ABSTRACT FROM AUTHOR]

Flufenamic acid (FFA) is a Biopharmaceutical Classification System- II (BCS-II) class drug with poor bioavailability and a lower dissolution rate. Particle size reduction is one of the conventional approaches to increase the dissolution rate and subsequently the bioavailability. The use of the liquid antisolvent method for particle size reduction of FFA was studied in this work. Ethanol and water were used as solvent and antisolvent, respectively. Experimental parameters such as solution concentration (10–40 mg/ml), flow rate (120–480 ml/h), temperature (298–328 K) and stirring speed (200–800 rpm) were investigated. Furthermore, the solid dispersion of FFA was prepared with polyvinylpyrrolidone K-30 (PVP K-30) with different weight ratios (1:1, 1:2, 1:3 and 1:4) and samples were characterized using SEM, FTIR and XRD techniques. The experimental investigation revealed that higher values of concentration, injection rate, stirring speed, along with lower temperature favored the formation of fine particles. SEM analysis revealed that the morphology of raw FFA changed from rock-like to rectangular-like after liquid antisolvent recrystallization. FTIR analysis validated the presence of hydrogen bonding between FFA and PVP in solid dispersion. XRD analysis showed no significant change in the crystallinity of the processed FFA. [ABSTRACT FROM AUTHOR]

The present study investigates the flow pattern characteristics of air-water co-current down-flow in millichannels. The experiments have been performed in glass tube of diameter 0.0042 and 0.008 m. The fluids are injected through Y entry the included angle between the Y arms being 45°, 90°, 135°, and 180° (T Entry). The investigation reveals that the flow patterns are function of tube-diameter, and angle of fluid entry. Interestingly, stratified flow has been observed for steeper Y entry section at low liquid flow rates. [ABSTRACT FROM AUTHOR]