Determination of indoor humidity profile using a whole-building hygrothermal model

During the design of a new building or retrofitting of an existing one, it is important to reliably assess the indoor humidity levels of the building as it can potentially affect the building envelope durability, occupants’ comfort and health risks associated with mould growth. Simplistic assumptions of indoor humidity profiles, which ignore the dynamic coupling of the indoor environment and building enclosure, may lead to inaccurate conclusions about the indoor environment and moisture performance of the building enclosure. In this paper, a whole-building hygrothermal model called HAMFitPlus, which takes into account the dynamic interactions between building envelope components, mechanical systems and indoor heat and moisture generation mechanisms, is used to assess the indoor humidity condition of an existing occupied house. HAMFitPlus is developed on SimuLink development platform and integrates COMSOL multiphysics with MatLab. The basic input parameters of the model are discussed in detail, and its simulation results are presented. In general, the HAMFitPlus simulation results are in good agreement with the measured data.

[1]  J. Timusk,et al.  Building science for a cold climate , 1984 .

[2]  Hr Trechsel.  Chapter 1—Moisture Primer , 2001 .

[3]  N. B. Hutcheon,et al.  Building Science for a Cold Climate , 1984 .

[4]  Tetsuo Hayashi,et al.  PROCEDURES FOR SEPARATING DIRECT AND DIFFUSE INSOLATION ON A HORIZONTAL SURFACE AND PREDICTION OF INSOLATION ON TILTED SURFACES , 1983 .

[5]  Paul Fazio,et al.  Transient model for coupled heat, air and moisture transfer through multilayered porous media , 2010 .

[6]  R. Jones.  Modelling water vapour conditions in buildings , 1993 .

[7]  Carsten Rode,et al.  Whole building hygrothermal simulation model , 2010 .

[8]  Fitsum Tariku,et al.  Whole building heat and moisture analysis , 2008 .

[9]  Frank Kreith,et al.  The CRC handbook of mechanical engineering , 1998 .

[10]  Refrigerating.  ASHRAE handbook of fundamentals , 1967 .

[11]  Vice President,et al.  AMERICAN SOCIETY OF HEATING, REFRIGERATION AND AIR CONDITIONING ENGINEERS INC. , 2007 .

[12]  Andreas K. Athienitis,et al.  Thermal Analysis and Design of Passive Solar Buildings , 2000 .

[13]  Paul Fazio,et al.  Modelling of indoor air humidity: the dynamic behaviour within an enclosure , 1992 .

[14]  P. Fanger,et al.  Impact of Temperature and Humidity on Perception of Indoor Air Quality During Immediate and Longer Whole‐Body Exposures , 1998 .

[15]  Hr Trechsel,et al.  Overview of ASTM MNL 40, Moisture Analysis and Condensation Control in Building Envelopes , 2001 .

[16]  S. M. Cornick,et al.  Characterization of Indoor Hygrothermal Conditions in Houses in Different Northern Climates , 2007 .

[17]  A. TenWolde,et al.  3746 VENTILATION , HUMIDITY , AND CONDENSATION IN MANUFACTURED HOUSES DURING WINTER , 2007 .

[18]  Paul Fazio,et al.  The need for an accurate indoor humidity model for building envelope performance analysis , 2009 .

[19]  George Tsongas,et al.  A PARAMETRICSTUDYOF WALLMOISTURE CONTENTS USING A REVISEDVARIABLE INDOOR RELATIVE HUMIDITYVERSION OF THE"MOIST"lRANSIENTHEAT AND MOISTURE TRANSFER MODEL , 1995 .

[20]  Paul Fazio,et al.  Integrated analysis of whole building heat, air and moisture transfer , 2010 .

[21]  vrt,et al.  Integrated heat, air and moisture modeling toolkit in Matlab , 2005 .

[22]  P. Fanger,et al.  Impact of Temperature and Humidity on the Perception of Indoor Air Quality , 1998 .

[23]  Tadj Oreszczyn,et al.  Condensation Targeter II: Modelling surface relative humidity to predict mould growth in dwellings , 1999 .

[24]  R. Jones.  Review paper: Indoor humidity calculation procedures , 1995 .

[25]  Povl Ole Fanger,et al.  Air humidity requirements for human comfort , 1999 .

[26]  Paul Fazio,et al.  The dynamic modelling of air humidity behaviour in a multi-zone space , 1993 .