Contentslistsavailableat ScienceDirect Chemical Physics Letters journal homepage: www.elsevier.com/locate/cplett Research paper PorousefectsonheattransferandionsdistributioninYSZusingmolecular dynamics simulation XuezhiWang a, ⁎ ,SrikanthPilla b,c,d ,JunweiChe e ,QingyingChen f a Department of Applied Physics, Chang′an University, Xi′an 710064, China b Department of Automotive Engineering, Clemson University, SC, USA c Department of Materials Science and Engineering, Clemson University, SC, USA d Clemson Composites Center, Clemson University, SC, USA e Department of Applied Physics, Xi’an Jiaotong University, Xi’an 710049, China f Department of Physics and Engineering Physics, The University of Tulsa, OK, USA HIGHLIGHTS • PorousefectsofheattransferandionsdistributioninYSZhavebeeninvestigated. • TypicalionspairsmovementshavebeencapturedinYSZsystemswithdiferentporetypes. • VDOSofscatteredphononinvariousYSZporoussystemshavebeenanalyzed. ARTICLEINFO Keywords: Ions distribution Yttria stablized zirconia Thermal property Porosity Molecular dynamics simulation ABSTRACT ThemutualefectsofheattransferandionsdistributiononYSZwithporousstructureshavebeeninvestigatedin thispaper.VariousofporousYSZmicrostructuresweresimulatedtoelucidatetherelationshipsofionsspacial distribution and heat transfer from atomic perspective. Typical ion movement and the phonon vibrational densityofstatewereinvestigatedinvariousporoussystems.Thesimulationresultsshowthatthermaltransport behaviorbondsclosetotheionsdistributioninporoussystems.Theionsdistributionnearbyporesinthesystem haveapredictablereductionefectsonthermaltransportbehavior,whichcouldleadtoadecreaseinthermal conductivity. 1. Introduction ThermalBarrierCoatings(TBCs)thatareusedforthetopcoatofgas turbines are composed primarily of Yttria stabilized zirconia (YSZ) [1–3].YSZ(6–8wt%Y 2 O 3 inZrO 2 )ischaracterizedbyanoutstanding performanceasTBCsmaterialswithin1200°C,ahighthermalexpan- sioncoefcientof10.7×10 −6 K −1 andathermalshockresistanceand lowthermalconductivityof2.1W −1 K −1 [4–6]. Although experiments have been undertaken to study its phase transition, oxygen difusion and thermal properties, undertaking an experimentatelevatedtemperaturesisstillagreatchallenge,thatmost of the details at the atomic level cannot be captured [7–9]. However, the Molecular Dynamics (MD) simulation is an excellent tool for studying those fundamental problems. Indeed, MD simulation studies have elucidated the oxygen ion difusion, the crystal and grain boundary structure, and the thermal property of YSZ [10–13]. However,themutualefectsofheattransferandionsspacialdistribu- tion on thermal property in YSZ porous systems has been the rare subjectofresearchwork. In this paper, we detail our investigation into the details of the mutual efects on thermal property of various YSZ porous systems at 1273 K. The displacement of ion pairs were studied in various YSZ poroussystems,andphononvibrationwasusedtodescribethethermal transportbehaviorinthosesystems.Resultswerethenusedtocraftan alternative approach to enhance the thermal property in YSZ porous systems. 2. Simulation details The MD simulations were performed by using LAMMPS code, the Maxwell-Boltzmanndistributionwasusedtotracktheinitialvelocities of all, and the Nose-Hoover method used to control the system https://doi.org/10.1016/j.cplett.2020.137339 Received11January2020;Receivedinrevisedform5March2020;Accepted9March2020 ⁎ Corresponding author. E-mail address: xzh_wang@chd.edu.cn (X.Wang). Chemical Physics Letters 747 (2020) 137339 Available online 10 March 2020 0009-2614/ © 2020 Published by Elsevier B.V. T