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56 Figures 11a, b: Calculation of hysteresis of moisture diffusivity (a) and sorption isotherm (b) Figs. 11a, b show how the hysteretic effects were manifested in the values of moisture diffusivity and sorption isotherm of concrete used by the model during the whole time period of 5‐years simulation. While the water vapour sorption parameters were mostly near to the center line of the area demarcated by the adsorption and desorption curves, the moisture diffusivities oscillated between the maximum and minimum values. Comparison of the effects of hysteresis of moisture transport and storage parameters Figs. 12a, b present a comparison of the effects of hysteresis of moisture transport and storage parameters on moisture content and relative humidity for a characteristic locality in concrete, 1 cm from the interface between concrete and thermal insulation. As for the relative humidity profiles, it is obvious that all values came close each other in the 5th year of simulation. Moisture content profiles were quite different. Results of simulation without hysteretic effect and with hysteresis of moisture diffusivity only were very similar, but they differed from the other simulations in a significant way. Besides, the yearly oscillations of water content were not steady yet after 5 years. Involving hysteretic effects of both moisture diffusivity and sorption isotherm caused the highest increase of moisture content in the chosen point. Similar results were also obtained for other points within the concrete part of the wall. Moisture content [m 3 /m 3 ] 0.08 0.07 0.06 0.05 0.04 0.03 0.02 365 730 1095 1460 1825 2100 Time [days] Without hysteresis With hysteresis SI With hysteresis κ With both hysteresis Relative humidity [-] 1 0.9 0.8 0.7 0.6 0.5 0.4 365 730 1095 1460 1825 2100 Time [days] Without hysteresis With hysteresis SI With hysteresis κ With both hysteresis Figures 12a, b: Moisture content (a) and relative humidity (b) in a characteristic locality in concrete, 1 cm from the interface between concrete and thermal insulation
Conclusions The computer simulations of coupled heat and moisture transport in this paper have shown that the application of hysteretic moisture transport and storage parameters can be considered as quite important in service life analyses of multi‐layered systems of porous building materials. The results indicated very significant differences in moisture and relative humidity profiles calculated using the model with hysteretic parameters and without hysteresis. As the differences were always on the dangerous side, it can be concluded that neglecting the hysteretic effects while desorption is in progress can lead to underestimation of damage risk due to water presence in a structure which is rather undesirable in any service life analysis. Acknowledgement This research has been supported by the Czech Ministry of Education, Youth and Sports, under project No MSM 6840770031. References [1] KÜNZEL, H. M., Simultaneous Heat and Moisture Transport in Building Components, PhD Thesis, IRB Verlag Stuttgart, 1995. [2] PEDERSEN, C. R., Combined Heat and Moisture Transfer in Building Constructions, PhD Thesis, Report 214. Thermal Insulation Laboratory, TU Denmark, 1990. [3] VEJMELKOVÁ, E. & ČERNÝ, R., Application of Alternative Silicate Binders in the Production of High Performance Materials Beneficial to The Environment. <strong>Proceedings</strong> of the 2008 World Sustainable Building <strong>Conference</strong> [CD‐ROM]. Balnarring, Victoria: ASN Events Pty Ltd, 2008, p. 520‐525, 2008. [4] PernIcová, R., PAVLÍKOVÁ, M., PAVLÍK, Z. & ČERNÝ, R., Vliv metakaolinu na mechanické, tepelné a vlhkostní vlastnosti vápenných omítek. Metakaolin 2007. Brno: VUT FAST, s. 70‐77, 2007 [5] ČERNÝ, R. & ROVNANÍKOVÁ, P., Transport Processes in Concrete, 1. ed. London: Spon Press, pp. 26–29, 2002. [6] PEL L., ČERNÝ, R. & PAVLÍK Z, Moisture and Ion Transport. WP5 2‐Years Report of the EU 6th Program Project SSPI‐CT‐2003‐501571. TU Eindhoven, Eindhoven, 2006. 57
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Thermophysics 2009 29 th and 30 th
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Content Ivan Baník, Jozefa Lukovi
Page 5 and 6: Measurement of the thermo‐physica
Page 7 and 8: As the right side of the previous r
Page 9 and 10: The initial vector k r in the k1, k
Page 11 and 12: 2.4 The computer programs testing T
Page 13 and 14: Investigation of moisture influence
Page 15 and 16: ⎛ t t ⎞ −1 ⋅ ln⎜ ⎝ tm t
Page 17 and 18: Density [kg.m -3 ] 620 600 580 560
Page 19 and 20: for a new building have to be great
Page 21 and 22: Fig.1. Photo of the hot ball sensor
Page 23 and 24: Fig.6.Left: formation of blocks. Ri
Page 25 and 26: 4. Conclusions With this experiment
Page 27 and 28: 1a. Three‐dimensional temperature
Page 29 and 30: n+ ∞ ( ) 4 ( ) ∑ π n= 1 ( 2 1)
Page 31 and 32: a 2 2 ( Fo) ⎛ l ⎞ r = ⎜ ⎟
Page 33 and 34: Substitution of ordinates of the in
Page 35 and 36: Moisture transport through porous m
Page 37 and 38: Data acquired through the hot ball
Page 39 and 40: In this way, the water spreading wa
Page 41 and 42: Thermal conductivity [W m -1 K -1 ]
Page 43 and 44: Relationship between relative permi
Page 45 and 46: ( ) i n Φ − Φ K i = ki i i, cri
Page 47 and 48: Figure 4: Comparison of measured an
Page 49 and 50: Computational modelling of coupled
Page 51 and 52: a ξ = d 2 ( lnκ − lnκ ) lnξ +
Page 53 and 54: on the results of experiments and c
Page 55: Figures 8a, b: Moisture content (a)
Page 59 and 60: properties as are the bulk density,
Page 61 and 62: elation determined from the measure
Page 63 and 64: In the evaluation of the difference
Page 65 and 66: Heat source I RT-Lab II Specimen Ch
Page 67 and 68: Thermal conductivity [W m -1 K -1 ]
Page 69 and 70: silicon glue epoxy probe hole Figur
Page 71 and 72: Computational modelling of temperat
Page 73 and 74: 1 2 3 EXT. INT. 5-15 50-60 375 5 Nu
Page 75 and 76: Fig. 4 shows a comparison of the re
Page 77 and 78: Envelope D Figs. 14, 15 present the
Page 79 and 80: Application of computational modell
Page 81 and 82: Table 2: Basic material characteris
Page 83 and 84: Temperature [K] 320 300 280 260 240
Page 85 and 86: Mineral wool has the same effect as
Page 87 and 88: Nowadays, most of concrete building
Page 89 and 90: Figure 2: Ceramic dessicator plate
Page 91 and 92: dessicators are decreased by the pe
Page 93 and 94: The surface water vapour diffusion
Page 95 and 96: where h is the Planck constant and
Page 97 and 98: (a) (b) Figure 2: Schematic picture
Page 99 and 100: [7] BLUM, V.; HART, G. L. W.; WALOR
Page 101 and 102: Analysis of moisture hysteresis of
Page 103 and 104: The water content during scanning b
Page 105 and 106: All analysed cellulose based materi
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Thermodilatometry of ceramics using
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of the dilatometric cell with the s
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thermal expansion / % 2 1,5 1 0,5 0
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[8] KAMSEU, E. ; LEONELLI, C. ; BOC
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heating, the temperatures were meas
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temperature difference [°C] 140 12
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temperature difference [°C] 180 16
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[4] ČÍČEL, B. - NOVÁK, I. - HOR
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space and the crystallization press
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20 mm face to the penetrating KNO3
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Cb [kg/m 3 (sample)] 1800 1600 1400
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D [m 2 /s] 1.0E-03 1.0E-04 1.0E-05
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Thermomechanical modelling of matur
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ε ε (velocity rates) a x , t . By
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ε ε w v The process of redistribu
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Conclusion In this paper we have br
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most popular among direct technique
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• Closed pores (not available for
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espective volume of inclusions frac
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Summary Among the indirect methods
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Thermal, hygric and salt‐related
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The water vapor diffusion coefficie
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Thermal properties Thermal conducti
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On the other hand, apparent moistur
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Thermal conductivity.. [Wm -1 K -1
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Properties of innovative materials
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or hygrothermal analysis of buildin
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where Da is the diffusion coefficie
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The bending and compressive strengt
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moisture diffusivity which was caus
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Abstract: Thermal conductivity in d
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, (5) where λ is thermal conductiv
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4.Measured values and calculation I
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Acknowledgements This research has
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3 Results During heating, the struc
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Acknowledgment This work was suppor
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mixture by short mixing, the mixtur
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detected by MIP and thus the intrus
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diffusion. The general Arrhenius eq
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Thermal conductivity measurement of
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S s o 2 4 4 λ ∇ T = wεσ ( T
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steel (20 W m ‐1 K ‐1 ) is arou
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significant larger cross‐section.
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Water and heat transport properties
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The open porosity ψ0 [%], bulk den
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Table 3: Basic material parameters
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Acknowledgements This research has
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comparison of results we can determ
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specimen and heat source R at infin
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6.E-04 4.E-04 ΔU (V) 2.E-04 0.E+00
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[3] KUBIČÁR Ľ. Pulse method of m
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silicate binders as partial replace
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Table 2. Mechanical properties HPC
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HPC Table 5. Water transport proper
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The results obtained for using high
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aerospace engineering, cryogenic en
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4 ⎡ ′ ⎤ Δθ( t) = ⎢ l ∫
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Alloy Components Weight Percent, [%
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Figure 8: Final results of the ther
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Figure 11: Preliminary results of t
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In case of the FeNi35, FeNi39 and F
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Experimental Methods Compressive st
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Type of mixture Water transport pro
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Thermal properties The thermal para
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Identification of Some Thermophysic
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Physical model of the direct proble
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2 ( λ − Bi) sin( λ) − 2λ Bic
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To calculate the sensitivity coeffi
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symmetry of the specimen when the t
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Figure 5: View of experimental setu
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During the inverse calculations the
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temperature dependence for the blac
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4. Conclusions The results of the t
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cross‐planar direction applying s
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3. Thermal diffusivity identificati
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Table 2: Effect of the convective h
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[2] BODZENTA, J.; BURAKA, B.; NOWAK
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doc. Ing. Jiří Vala, CSc. Brno Un
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