Investigation on the Performance of a Compact Three-Fluid Combined Membrane Contactor for Dehumidification in Electric Vehicles

In this paper, the performance of a compact Three-Fluid Combined Membrane Contactor (3F-CMC) is investigated using Computational Fluid Dynamics (CFD), supported and validated with a good agreement by an experimental campaign made on a fully working prototype. This internally-cooled membrane contactor is the core component of a hybrid air conditioning system for electric vehicles (EVs) developed in a successful H2020 project called XERIC. In the adopted numerical approach, the conjugate heat and mass transfer inside the 3F-CMC is described by non-isothermal incompressible flows and vapor transport through a PTFE hydrophobic membrane. The sensitivity of the 3F-CMC performance to air/desiccant flow rates, temperature, humidity, and desiccant concentration is analyzed numerically through the validated CFD codes. According to this study, the moisture removal increases by the inlet humidity ratio, nearly linearly. Under the considered conditions (where the inlet air temperature is 26.2C), when the inlet relative humidity (RH) is 75% the moisture removal is about 450% higher than the case RH = 37%, while the absorption effectiveness declines about 45%. Furthermore, this study shows that the amount of absorbed vapor flux rises by increasing the airflow rate; on the other hand, the higher the airflow rate, the lower is the overall absorption efficiency of the 3F-CMC. This investigation gives important suggestions on how to properly operate a 3F-CMC in order to achieve the requested performance, especially in hot and humid climates

LAMMPS lb/fluid fix version 2: Improved hydrodynamic forces implemented into LAMMPS through a lattice-Boltzmann fluid

The first version of this code (Mackay et al., 2013) [10] implemented long-range hydrodynamic interactions into the open-source molecular dynamics package LAMMPS. This was done through the creation of a fix, lb/fluidwhich was subsequently included as a user-package in the main LAMMPS distribution. Here we substantially update this package by making improvements to its accuracy, adding significant new features, and by simplifying the use of the package. A new two-pass interpolation and spreading scheme is introduced which results in the improved accuracy and numerical stability. New features include new output options, several added computes, and mesh geometry option suitable for micro- and nano-fluidic device simulations. The original package could require fairly careful calibration to obtain accurate thermostating and accurate reproduction of properties related to the hydrodynamic size of objects such as colloids. This process has now been largely automated so that the default settings should suffice for most applications. Program summary Program title: fix lb/fluid CPC Library link to program files: https://doi.org/10.17632/2289cnrdtz.1 Licensing provisions: GPLv3 Programming language: C++ Journal reference of previous version: Comput. Phys. Commun. 184 (2013) 2021-2031. Does the new version supersede the previous version?: Yes Reasons for the new version: The new version improves accuracy, adds new features, and simplifies the use of the package. Summary of revisions: A new two-pass interpolation and spreading scheme is introduced to relate properties on the fluid mesh to off-lattice particle properties. New features include output options, several added computes, and mesh geometry suitable for micro- and nano-fluidic device simulations. Calibration processes have been largely automated so that the default settings should suffice for most applications. Nature of problem: The inclusion of long-range hydrodynamic effects into molecular dynamics simulations requires the presence of an explicit solvent. Prior to the implementation of this fix, the only option for incorporating such a solvent into a LAMMPS [1] simulation is the explicit inclusion of each of the individual solvent molecules. This is obviously quite computationally intensive, and for large system sizes can quickly become impractical. Solution method: As an alternative, we have implemented a coarse-grained model for the fluid, simplifying the problem, while retaining the solvent degrees of freedom. We use a thermal latticeBoltzmann model for the fluid, which is coupled to the molecular dynamics particles at each fluid time step. (C) 2022 The Author(s). Published by Elsevier B.V.Peer reviewe

Aloysia citriodora Palau (lemon verbena) for insomnia patients: A randomized, double-blind, placebo-controlled clinical trial of efficacy and safety

Aloysia citriodora (A. citriodora) has a long history of traditional use for sedation and treatment of insomnia in different societies. This study was carried out to assess the efficacy of A. citriodora in patients with insomnia. One hundred patients were randomly divided into two groups of A. citriodora (total essential oil 1.66 mg/10 ml and total amount of flavonoid in terms of quercetin 3.22 mg/10 ml of the syrup) and placebo. They were advised to use 10 cc of the syrups; an hour before the bedtime for a period of 4 weeks. Participants were assessed using Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) questionnaires at the baseline and then 2 and 4 weeks after the enrollment. Mean scores of global PSQI and its four components including sleep latency, habitual sleep efficiency, daytime dysfunction, and subjective sleep quality and also ISI score in the A. citriodora group improved significantly after 4 weeks of treatment when compared with the placebo group (p < 0.001, for all of them). Also, improvement of global score of PSQI and ISI was observed in the intervention group as compared with the placebo group, 2 weeks after the enrollment (p < 0.001). The results of this study showed that oral intake of A. citriodora can be suggested as a complementary treatment for patients with insomnia. © 2018 John Wiley & Sons, Ltd