1998 Fiscal Year Final Research Report Summary
An analysis of freezing/thawing process in building wall
| Project/Area Number |
09650658
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Architectural environment/equipment
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| Research Institution | Osaka-sangyo University |
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Principal Investigator |
MATSUMOTO Mamoru Faculty of Engineering, Osaka-sangyo University Professor, 工学部, 教授 (10031064)
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| Project Period (FY) |
1997 – 1998
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| Keywords | Freezing and thawing / Transient heat and moisture transfer / Porous media / Prevention to freeze damage / Numerical analysis / Effect of hysteresis / Mathematical model / Simulation |
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| Research Abstract |
(1) Governing equations are derived for simultaneoous heat and moisture transfer which can be applied to freezing and thawing processes. Closing of the equations is discusse.
(2) For closing the governing equations, equilibrium relations of the liquid water content and moisture (chemical) potential under freezing regime are presented and discussed how to measure or how to estimate. Along with, the freezing point depression is shown as a function of moisture (chemical) potential.
(3) A quasi-linearized equation are derived, based on simautaneous heat and moisture transfer equations. The equations derived are Linear but time variant and coefficients of the equations are obtained by solving original nonlinaer equations on the paticular but arbitrary boundary conditions.
(4) As an example of simulation, freezing and thawing process in the building wall, thermally insulated by glass wool on inner side of the wall and layered by moisture barrier at outer surface, is numerically analyzed.
(5) A numerical method to analyze transient beat and moisture transfer considering hysteresis effects are presented.
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