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This paper investigates experimentally heat transfer during evaporation of n-pentane inside a parallel multiport mini-channel. The experimental tests are conducted in a test section within five rectangular stainless steel minichannels. The local heat transfer coefficient is measured for different testing conditions to study the influence of mass flux (G = 113–187 kg/m2·s) and heat flux (200 W–320 W). For low vapor quality region [0–0.4], the domination of nucleate boiling is significant while the forced convective boiling is obtained for high vapor quality region. A comparison of the experimental results with existing correlations is carried out by calculating mean absolute deviation which led to some diverging correlations >100% while others present a good estimation around 30%. Thus, a new correlation is developed to predict local heat transfer with MAE of 22% based on the experimental results. A considerable attention is also paid to pressure drop effects by measuring experimentally pressure drop in the minichannels and develop a new correlation to evaluate frictional pressure drop. [ABSTRACT FROM AUTHOR]

In this paper, the fractal-like multiexponential (f-mexp) equation was modified by introducing the fractional fractal exponent to each stage of the adsorption process. The new equation was used for the analysis of kinetic adsorption of copper onto treated attapulgite. The modeling results show that the modified f-mexp equation fits properly the kinetic data in comparison with the classical and fractal-like kinetic models tested. The effect of varying the initial concentration of the adsorbate on the kinetic parameters was analyzed. Artificial neural networks were applied for the prediction of adsorption efficiency. Outcomes indicate that the multilayer perceptron neural network can predict the removal of copper from aqueous solutions more accurately under different experimental conditions than the single-layer feedforward neural network. Single-site and multisite occupancy adsorption models were used for the analysis of experimental adsorption equilibrium data of copper onto treated attapulgite. The modeling results show that there is no multisite occupancy effect and that the equilibrium data fit well the Langmuir-Freundlich isotherm., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)