An experimental study on drying characteristics and kinetics of figs (Ficuscarica)

In this study, the thin-layer drying characteristics of Figs (Ficus carica) are investigated in a pilot scale forced convective dryer. Experiments carried out under various operating conditions including air temperature (40, 50, 60, 70°C), air velocity (0.65, 2.1, 3.45, 4.85 m/s) and air humidity (0.005, 0.010, 0.015 kg/kg) and the effects of these operating conditions on the drying kinetics and the drying time determined. The obtained kinetics data are fitted into a conceptually developed model. The equilibrium moisture content of the dried figs is determined at different values of temperature and relative humidity of air. The values of effective moisture diffusivity (Deff) are obtained from the Fick’s second law and a temperature-dependent relation is proposed for this parameter

An experimental study on drying characteristics and kinetics of figs (Ficus carica)

In this study, the thin-layer drying characteristics of Figs (Ficus carica) are investigated in a pilot scale forced convective dryer. Experiments carried out under various operating conditions including air temperature (40, 50, 60, 70°C), air velocity (0.65, 2.1, 3.45, 4.85 m/s) and air humidity (0.005, 0.010, 0.015 kg/kg) and the effects of these operating conditions on the drying kinetics and the drying time determined. The obtained kinetics data are fitted into a conceptually developed model. The equilibrium moisture content of the dried figs is determined at different values of temperature and relative humidity of air. The values of effective moisture diffusivity (Deff) are obtained from the Fick’s second law and a temperature-dependent relation is proposed for this parameter

Effects of enhanced fuel with Mg-doped Fe3O4 nanoparticles on combustion of a compression ignition engine:Influence of Mg cation concentration

The present study focuses on the synthesis of novel catalytic nanoparticles and their effect on combustion, performance, and emission characteristics of a diesel engine. For this purpose, Mg cations were doped into a Fe3O4 lattice to form MgxFe(3-x)O4 (x = 0.25, 0.5, 0.75, and 1) using a solution combustion method. Comprehensive characterization studies were carried out to assess the oxygen storage capacity (OSC) and the properties of final powders. These synthesized samples were dispersed in a diesel-biodiesel blend fuel with a concentration of 90 ppm. Assessment of the structure of the samples proved the formation of MgFe2O4 structures, suggesting that Mg cations were embedded into the Fe3O4 and formed appropriate structures. The OSC was reduced from 8661 μmol/g (Mg0·25Fe2·75O4) to 7069 μmol/g (MgFe2O4) by introducing additional Mg cations. When run on a six-cylinder diesel engine, the fuel mixed from the synthesized samples did not significantly influence the indicated power (IP), brake specific fuel consumption (BSFC) or the brake thermal efficiency (BTE). In addition to the obtained result for the OSC of the sample, which declined by increasing the Mg concentration in the Fe3O4 lattice, using the sample with the highest concentration of Mg cations, a considerable reduction was detected in the major exhaust emissions such as HC (56.5%), PM1 (35%), and PN (37%) and a slight decrease occurred in CO (7%) compared to the engine fueled by pure fuel. Based on the experimental engine results, the MgFe2O4 sample can be considered as a useful nanocatalyst for mixing in the fuels for emissions reduction.</p

Synthesis and evaluation of catalytic activity of NiFe2O4 nanoparticles in a diesel engine : An experimental investigation and Multi-Criteria Decision Making approach

Exposure to gaseous and particulate matter (PM) emissions from engine combustion can result in severe human health risks. Although blending biodiesel-diesel fuel presents reduction in diesel engine emissions, mixing fuel with an oxidation catalyst with considerable oxygen storage capacity (OSC) characteristic might better reduce the harmful engine emissions. In the present study, NiFe2O4 nanoparticles were synthesized via the combustion method. X-ray diffraction analysis, Raman spectroscopy and temperature programmed reduction techniques were used to assess the structure and OSC of the nanoparticles. The data was collected using a diesel engine in fuel blends of "B20–NiFe2O4" under steady state conditions, at 25, 50 and 75% of engine full load, and at a constant engine speed of 1500 rpm. The Analysis of variance (ANOVA) approach was used to interrupt the engine outputs. The soot samples emitted from diesel engine fuel containing B20–NiFe2O4 were collected for transmission electron microscopy analysis to determine their morphology and nanostructure. NiFe2O4 nanoparticles showed spinel structure with an OSC of 13580 μmol/g. There was a considerable reduction in exhausted particles with the B20–NiFe2O4 blend. The average emission reductions for hydrocarbons, carbon monoxide, particle number, and particle mass were 44.3%, 12%, 26%, and 30%, respectively. The soot particle internal structure showed that for the B20–NiFe2O4 blend, particles were structurally arranged around the outer region of the core. Finally, the Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) was performed using the experimental data (all investigated parameters) to rank the alternatives. The optimization result reveals that B20–NiFe2O4 is a good alternative for different conditions of engine loading. By using the TOPSIS ranking, the engine can be operated in the most optimal manner at 50% load using B20–NiFe2O4.</p