The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

Baolin Wang - One of the best experts on this subject based on the ideXlab platform.

  • The thermal shock resistance prediction of porous ceramic sandwich structures with temperature-Dependent Material properties
    Ceramics International, 2019
    Co-Authors: Li Zhenfen, K.f. Wang, Baolin Wang, Shuai Guo
    Abstract:

    Abstract A general numerical model to predict the thermal shock resistance of porous ceramic sandwich (PCS) structures with temperature-Dependent Material properties is developed. Knowledge of the temperature distribution and associated thermal stress in PCS panel is determined by the finite element method of coupled thermoelasticity. The present work considers the hot/cold shock induced center/edge cracks and measures the time-varied thermal stress intensity factors at the crack tip area. The roles of crack length, relative density of foam core, thermal shock load and geometric parameters of the PCS structures are examined. Moreover, fracture failure analysis of the whole PCS structures is carried out and crack propagation manners are detected. The thermal shock resistance curves of the structures are provided and the critical thermal shock temperatures are estimated for any selected characteristic Materials. Results reveal that the thermal shock resistance of the PCS structures will be dramatically underestimated with the ignorance of temperature-Dependent Material properties. The analysis model of this paper provides a rapid prediction of thermal shock behavior of PCS structures at arbitrary temperatures.

  • thermal shock resistance of ceramics with temperature Dependent Material properties at elevated temperature
    Acta Materialia, 2011
    Co-Authors: Jiecai Han, Baolin Wang
    Abstract:

    Abstract This paper conducts thermal shock case studies for three typical thermal shock specimens that are important in thermal shock tests: a ceramic layer under a hot shock, a ceramic layer under a cold shock and a ceramic coating under a cold shock. All Material properties are assumed to be functions of temperature. The temperature field without cracking is obtained by using the finite element/finite difference method. Time-varied thermal stress intensity factors are obtained by using the weight function method for various parameters of the problem. The thermal shock resistance curves are obtained and the critical size parameters, which control the applicability of the stress-based criterion and the fracture-mechanics-based criterion for the determination of the thermal shock resistance of ceramics, are explored. The studies demonstrate the significance of incorporating temperature-Dependent Material properties on the thermal shock resistance of ceramic Materials for high-temperature applications. The dominant property change responsible for the improvement is the significant reduction in Young’s modulus with increasing temperature. As a result, the thermal stress level is reduced considerably and the thermal shock resistance of the ceramic Material is improved greatly.

Shuai Guo - One of the best experts on this subject based on the ideXlab platform.

  • The thermal shock resistance prediction of porous ceramic sandwich structures with temperature-Dependent Material properties
    Ceramics International, 2019
    Co-Authors: Li Zhenfen, K.f. Wang, Baolin Wang, Shuai Guo
    Abstract:

    Abstract A general numerical model to predict the thermal shock resistance of porous ceramic sandwich (PCS) structures with temperature-Dependent Material properties is developed. Knowledge of the temperature distribution and associated thermal stress in PCS panel is determined by the finite element method of coupled thermoelasticity. The present work considers the hot/cold shock induced center/edge cracks and measures the time-varied thermal stress intensity factors at the crack tip area. The roles of crack length, relative density of foam core, thermal shock load and geometric parameters of the PCS structures are examined. Moreover, fracture failure analysis of the whole PCS structures is carried out and crack propagation manners are detected. The thermal shock resistance curves of the structures are provided and the critical thermal shock temperatures are estimated for any selected characteristic Materials. Results reveal that the thermal shock resistance of the PCS structures will be dramatically underestimated with the ignorance of temperature-Dependent Material properties. The analysis model of this paper provides a rapid prediction of thermal shock behavior of PCS structures at arbitrary temperatures.

Vít Průša - One of the best experts on this subject based on the ideXlab platform.

  • Viscoelastic rate type fluids with temperature Dependent Material parameters -- stability of the rest state
    2017
    Co-Authors: Judith Stein, Vít Průša
    Abstract:

    We study the dynamics of small perturbations to the rest state of a viscoelastic rate type fluid with temperature Dependent Material parameters. We show that if the Material parameters are chosen appropriately, then the quiescent state of the fluid filling an isolated (mechanically, thermally) vessel is a stable state. The outlined analysis explicitly documents the importance of thermodynamic analysis in the development of advanced models for complex fluids.

  • On thermodynamics of incompressible viscoelastic rate type fluids with temperature Dependent Material coefficients
    International Journal of Non-Linear Mechanics, 2017
    Co-Authors: Jaroslav Hron, Vít Průša, Vojtěch Miloš, Ondřej Souček, Karel Tůma
    Abstract:

    Abstract We derive a class of thermodynamically consistent variants of Maxwell/Oldroyd-B type models for incompressible viscoelastic fluids. In particular, we study the models that allow one to consider temperature Dependent Material coefficients. This naturally calls for the formulation of a temperature evolution equation that would accompany the evolution equations for the mechanical quantities. The evolution equation for the temperature is explicitly formulated, and it is shown to be consistent with the laws of thermodynamics and the evolution equations for the mechanical quantities. The temperature evolution equation contains terms that are ignored or even not thought of in most of the practically oriented (computational) works dealing with this class of fluids. The impact of the additional terms in the temperature evolution equation on the flow dynamics is documented by the solution of simple initial/boundary value problems.

  • On thermodynamics of viscoelastic rate type fluids with temperature Dependent Material coefficients
    arXiv: Fluid Dynamics, 2016
    Co-Authors: Jaroslav Hron, Vít Průša, Vojtěch Miloš, Ondřej Souček, Karel Tůma
    Abstract:

    We derive a class of thermodynamically consistent variants of Maxwell/Oldroyd-B type models for viscoelastic fluids. In particular, we study the models that allow one to consider temperature Dependent Material coefficients. This naturally calls for the formulation of a temperature evolution equation that would accompany the evolution equations for the mechanical quantities. The evolution equation for the temperature is explicitly formulated, and it is shown to be consistent with the laws of thermodynamics and the evolution equations for the mechanical quantities. The temperature evolution equation contains terms that are ignored or even not thought of in most of the works dealing with this class of fluids. The impact of the additional terms in the temperature evolution equation on the flow dynamics is documented by the solution of simple initial/boundary value problems.

Jiecai Han - One of the best experts on this subject based on the ideXlab platform.

  • thermal shock resistance of ceramics with temperature Dependent Material properties at elevated temperature
    Acta Materialia, 2011
    Co-Authors: Jiecai Han, Baolin Wang
    Abstract:

    Abstract This paper conducts thermal shock case studies for three typical thermal shock specimens that are important in thermal shock tests: a ceramic layer under a hot shock, a ceramic layer under a cold shock and a ceramic coating under a cold shock. All Material properties are assumed to be functions of temperature. The temperature field without cracking is obtained by using the finite element/finite difference method. Time-varied thermal stress intensity factors are obtained by using the weight function method for various parameters of the problem. The thermal shock resistance curves are obtained and the critical size parameters, which control the applicability of the stress-based criterion and the fracture-mechanics-based criterion for the determination of the thermal shock resistance of ceramics, are explored. The studies demonstrate the significance of incorporating temperature-Dependent Material properties on the thermal shock resistance of ceramic Materials for high-temperature applications. The dominant property change responsible for the improvement is the significant reduction in Young’s modulus with increasing temperature. As a result, the thermal stress level is reduced considerably and the thermal shock resistance of the ceramic Material is improved greatly.

Karel Tůma - One of the best experts on this subject based on the ideXlab platform.

  • On thermodynamics of incompressible viscoelastic rate type fluids with temperature Dependent Material coefficients
    International Journal of Non-Linear Mechanics, 2017
    Co-Authors: Jaroslav Hron, Vít Průša, Vojtěch Miloš, Ondřej Souček, Karel Tůma
    Abstract:

    Abstract We derive a class of thermodynamically consistent variants of Maxwell/Oldroyd-B type models for incompressible viscoelastic fluids. In particular, we study the models that allow one to consider temperature Dependent Material coefficients. This naturally calls for the formulation of a temperature evolution equation that would accompany the evolution equations for the mechanical quantities. The evolution equation for the temperature is explicitly formulated, and it is shown to be consistent with the laws of thermodynamics and the evolution equations for the mechanical quantities. The temperature evolution equation contains terms that are ignored or even not thought of in most of the practically oriented (computational) works dealing with this class of fluids. The impact of the additional terms in the temperature evolution equation on the flow dynamics is documented by the solution of simple initial/boundary value problems.

  • On thermodynamics of viscoelastic rate type fluids with temperature Dependent Material coefficients
    arXiv: Fluid Dynamics, 2016
    Co-Authors: Jaroslav Hron, Vít Průša, Vojtěch Miloš, Ondřej Souček, Karel Tůma
    Abstract:

    We derive a class of thermodynamically consistent variants of Maxwell/Oldroyd-B type models for viscoelastic fluids. In particular, we study the models that allow one to consider temperature Dependent Material coefficients. This naturally calls for the formulation of a temperature evolution equation that would accompany the evolution equations for the mechanical quantities. The evolution equation for the temperature is explicitly formulated, and it is shown to be consistent with the laws of thermodynamics and the evolution equations for the mechanical quantities. The temperature evolution equation contains terms that are ignored or even not thought of in most of the works dealing with this class of fluids. The impact of the additional terms in the temperature evolution equation on the flow dynamics is documented by the solution of simple initial/boundary value problems.