A method to analyze the transient hygrothermal behaviour of building materials and components: Dissertation

Reijo Kohonen

Research output: ThesisDissertation

Abstract

A method has been introduced for the analysis of the hygrothermal behaviour of building materials and construction.The model equations for coupled heat and mass transfer used in the computer code TRATMO and in the determination of hygrothermal transport properties of materials are derived using the local volume averaging technique.In the energy balance equation the conduction, convection and accumulation of heat are considered as well as the generation of heat due to interstitial phase changes.The corresponding accumulation of moisture, diffusion in gas phase, surface diffusion and viscous flow of water vapour are considered in the moisture balance equation together with capillary and viscous flows of liquid water.Also introduced are methods for determining the diffusion coefficient of water vapour, moisture diffusivity and permeability as well as thermal conductivity and capacity.The numerical algorithm for the system of IWO coupled diffusion convection type equations used in the computer code TRATMO has been formulated using non-equidistance space differentiation and the trapetzoidal rule for the time derivative.The accuracy of the numerical algorithm is verified with an analytical solution of the model equations.In addition, a number of laboratory and field tests have been carried out in order to verify the validity of TRATMO.
Original languageEnglish
QualificationDoctor Degree
Awarding Institution
  • Helsinki University of Technology
Place of PublicationEspoo
Publisher
Print ISBNs951-38-2020-3
Publication statusPublished - 1984
MoE publication typeG4 Doctoral dissertation (monograph)

Fingerprint

viscous flow
moisture
water vapor
convection
building construction
thermal conductivity
diffusivity
energy balance
heat transfer
mass transfer
method
building component
permeability
liquid
gas
water
code
test
laboratory
properties of materials

Keywords

  • construction materials
  • porous materials
  • moisture
  • heat transfer

Cite this

Kohonen, Reijo. / A method to analyze the transient hygrothermal behaviour of building materials and components : Dissertation. Espoo : VTT Technical Research Centre of Finland, 1984. 89 p.
@phdthesis{2856dc64b9e44e01b63fecf811824156,
title = "A method to analyze the transient hygrothermal behaviour of building materials and components: Dissertation",
abstract = "A method has been introduced for the analysis of the hygrothermal behaviour of building materials and construction.The model equations for coupled heat and mass transfer used in the computer code TRATMO and in the determination of hygrothermal transport properties of materials are derived using the local volume averaging technique.In the energy balance equation the conduction, convection and accumulation of heat are considered as well as the generation of heat due to interstitial phase changes.The corresponding accumulation of moisture, diffusion in gas phase, surface diffusion and viscous flow of water vapour are considered in the moisture balance equation together with capillary and viscous flows of liquid water.Also introduced are methods for determining the diffusion coefficient of water vapour, moisture diffusivity and permeability as well as thermal conductivity and capacity.The numerical algorithm for the system of IWO coupled diffusion convection type equations used in the computer code TRATMO has been formulated using non-equidistance space differentiation and the trapetzoidal rule for the time derivative.The accuracy of the numerical algorithm is verified with an analytical solution of the model equations.In addition, a number of laboratory and field tests have been carried out in order to verify the validity of TRATMO.",
keywords = "construction materials, porous materials, moisture, heat transfer",
author = "Reijo Kohonen",
year = "1984",
language = "English",
isbn = "951-38-2020-3",
series = "Technical Research Centre of Finland. Publications",
publisher = "VTT Technical Research Centre of Finland",
number = "21",
address = "Finland",
school = "Helsinki University of Technology",

}

Kohonen, R 1984, 'A method to analyze the transient hygrothermal behaviour of building materials and components: Dissertation', Doctor Degree, Helsinki University of Technology, Espoo.

A method to analyze the transient hygrothermal behaviour of building materials and components : Dissertation. / Kohonen, Reijo.

Espoo : VTT Technical Research Centre of Finland, 1984. 89 p.

Research output: ThesisDissertation

TY - THES

T1 - A method to analyze the transient hygrothermal behaviour of building materials and components

T2 - Dissertation

AU - Kohonen, Reijo

PY - 1984

Y1 - 1984

N2 - A method has been introduced for the analysis of the hygrothermal behaviour of building materials and construction.The model equations for coupled heat and mass transfer used in the computer code TRATMO and in the determination of hygrothermal transport properties of materials are derived using the local volume averaging technique.In the energy balance equation the conduction, convection and accumulation of heat are considered as well as the generation of heat due to interstitial phase changes.The corresponding accumulation of moisture, diffusion in gas phase, surface diffusion and viscous flow of water vapour are considered in the moisture balance equation together with capillary and viscous flows of liquid water.Also introduced are methods for determining the diffusion coefficient of water vapour, moisture diffusivity and permeability as well as thermal conductivity and capacity.The numerical algorithm for the system of IWO coupled diffusion convection type equations used in the computer code TRATMO has been formulated using non-equidistance space differentiation and the trapetzoidal rule for the time derivative.The accuracy of the numerical algorithm is verified with an analytical solution of the model equations.In addition, a number of laboratory and field tests have been carried out in order to verify the validity of TRATMO.

AB - A method has been introduced for the analysis of the hygrothermal behaviour of building materials and construction.The model equations for coupled heat and mass transfer used in the computer code TRATMO and in the determination of hygrothermal transport properties of materials are derived using the local volume averaging technique.In the energy balance equation the conduction, convection and accumulation of heat are considered as well as the generation of heat due to interstitial phase changes.The corresponding accumulation of moisture, diffusion in gas phase, surface diffusion and viscous flow of water vapour are considered in the moisture balance equation together with capillary and viscous flows of liquid water.Also introduced are methods for determining the diffusion coefficient of water vapour, moisture diffusivity and permeability as well as thermal conductivity and capacity.The numerical algorithm for the system of IWO coupled diffusion convection type equations used in the computer code TRATMO has been formulated using non-equidistance space differentiation and the trapetzoidal rule for the time derivative.The accuracy of the numerical algorithm is verified with an analytical solution of the model equations.In addition, a number of laboratory and field tests have been carried out in order to verify the validity of TRATMO.

KW - construction materials

KW - porous materials

KW - moisture

KW - heat transfer

M3 - Dissertation

SN - 951-38-2020-3

T3 - Technical Research Centre of Finland. Publications

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Kohonen R. A method to analyze the transient hygrothermal behaviour of building materials and components: Dissertation. Espoo: VTT Technical Research Centre of Finland, 1984. 89 p.