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250 specific heat, J/kg/K 1600 1400 1200 1000 800 600 FOAMGLAS (BLACK), ρ=132 kg/m 3 DSC Perkin Elmer Pyris 1 ISOMET 2104 Inverse method 0 20 40 60 80 100 120 140 temperature, o C Figure 12: Specific heat of black foamglas – DSC Perkin Elmer Pyris 1, ISOMET 2104 vs. inverse method However, the situation is changing when the results of the specific heat obtained by various techniques are compared to each other (see Figure 12). This time the values of the specific heat obtained using the ISOMET 2104 with surface probe API 210411 were too distant from the exact ones (DSC‐technique). Because the results of the specific heat investigations obtained using ISOMET 2104 were too distant from the DSC results we have decided to repeat them. This time the sample made of black foamglas was put into the oven (see Figure 5) and the surface probe and the sample were covered by a cotton wool in order to ensure the same experimental conditions as they were when the inverse method was used. At each temperature set in the oven the sample was kept so long in the oven to reach the temperature equilibrium of the system consisted of the sample ‐ surface probe ‐ oven. It lasted from 9 to 11 hours for each temperature set in the oven. The re‐ measurement results obtained by using the ISOMET 2104 are given in Table 2. Table 2: The re‐measurement results of the black foamglas obtained by using the ISOMET 2104 Temperature Thermal conductivity Specific heat Thermal diffusivity [ °C] [W/m/K] [ J/kg/K] [m2/s] 30 0.0470 1015.2 0.352⋅10‐6 40 0.0493 1068.2 0.350⋅10‐6 50 0.0558 1386.4 0.305⋅10‐6 The re‐measurement results given in Table 2 revealed that the values of the thermal conductivity of the black foamglas were similar to those presented in Figure 11 but the values of the specific heat results exceeded the manufacturerʹs acceptable range of accuracy (more than 15%)
4. Conclusions The results of the thermal conductivity and the specific heat identification by the inverse method within temperature range (30 – 90) 0 C are consistent with results obtained by using DSC and Plate Apparatus. Average absolute discrepancy with respect to cp (DSC) equals was equal to 10.9% and with respect to λ (Plate Apparatus) 6.6%. The discrepancy results of the specific heat measurements by using ISOMET 2104 vs. DSC method were bigger than 15% what was inconsistent with the manufacturer declaration of the accepted accuracy. Acknowledgements This research work was supported by the Military University of Technology internal grants GW‐HB No. 703 and 701. The Authors would like to express their gratitude to Professor A. Panas for delivering the research results of the specific heat of black foamglas using DSC Perkin‐Elmer Pyris 1 micro‐ calorimeter. References [1] V. BOHÁČ, P. DIEŠKA, Ľ. KUBIČÁR, The progress in development of new models for pulse transient method, Proc. THERMOPHYSICS 2007, 24‐33, October 11 – 12, 2007, Kočovce chateau, Slovakia. [2] L. VOZÁR, T. ŠRÁMKOVÁ, Simultaneous measurement of axial and radial thermal diffusivities of anisotropic media by the radial‐heat flow step‐heating method, High Temp – High Press, 29 (1997), 183‐190. [3] Ľ. KUBIČÁR, V. VRETENÁR, V. ŠTOFANIK, V. Boháč, Hot‐ball method for measuring thermal conductivity, Int. J. Thermophysics, DOI 10.1007/s10765‐008‐0544‐4. [4] J. ZMYWACZYK, Estimation of thermophysical parameters of solids by using of selected methods of optimization, DSc Thesis, Warszawa WAT 2006 (in Polish). [5] A. PANAS, J. ZMYWACZYK, DSC Specific heat measurements of a Black Foamglas thermal insula tor, Private Communication 2009. 251
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Thermophysics 2009 29 th and 30 th
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Content Ivan Baník, Jozefa Lukovi
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Measurement of the thermo‐physica
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As the right side of the previous r
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The initial vector k r in the k1, k
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2.4 The computer programs testing T
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Investigation of moisture influence
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⎛ t t ⎞ −1 ⋅ ln⎜ ⎝ tm t
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Density [kg.m -3 ] 620 600 580 560
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for a new building have to be great
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Fig.1. Photo of the hot ball sensor
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Fig.6.Left: formation of blocks. Ri
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4. Conclusions With this experiment
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1a. Three‐dimensional temperature
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n+ ∞ ( ) 4 ( ) ∑ π n= 1 ( 2 1)
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a 2 2 ( Fo) ⎛ l ⎞ r = ⎜ ⎟
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Substitution of ordinates of the in
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Moisture transport through porous m
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Data acquired through the hot ball
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In this way, the water spreading wa
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Thermal conductivity [W m -1 K -1 ]
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Relationship between relative permi
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( ) i n Φ − Φ K i = ki i i, cri
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Figure 4: Comparison of measured an
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Computational modelling of coupled
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a ξ = d 2 ( lnκ − lnκ ) lnξ +
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on the results of experiments and c
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Figures 8a, b: Moisture content (a)
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Conclusions The computer simulation
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properties as are the bulk density,
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elation determined from the measure
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In the evaluation of the difference
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Heat source I RT-Lab II Specimen Ch
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Thermal conductivity [W m -1 K -1 ]
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silicon glue epoxy probe hole Figur
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Computational modelling of temperat
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1 2 3 EXT. INT. 5-15 50-60 375 5 Nu
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Fig. 4 shows a comparison of the re
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Envelope D Figs. 14, 15 present the
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Application of computational modell
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Table 2: Basic material characteris
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Temperature [K] 320 300 280 260 240
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Mineral wool has the same effect as
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Nowadays, most of concrete building
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Figure 2: Ceramic dessicator plate
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dessicators are decreased by the pe
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The surface water vapour diffusion
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where h is the Planck constant and
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(a) (b) Figure 2: Schematic picture
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[7] BLUM, V.; HART, G. L. W.; WALOR
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Analysis of moisture hysteresis of
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The water content during scanning b
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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
Page 199 and 200: Acknowledgements This research has
Page 201 and 202: comparison of results we can determ
Page 203 and 204: specimen and heat source R at infin
Page 205 and 206: 6.E-04 4.E-04 ΔU (V) 2.E-04 0.E+00
Page 207 and 208: [3] KUBIČÁR Ľ. Pulse method of m
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Page 211 and 212: Table 2. Mechanical properties HPC
Page 213 and 214: HPC Table 5. Water transport proper
Page 215 and 216: The results obtained for using high
Page 217 and 218: aerospace engineering, cryogenic en
Page 219 and 220: 4 ⎡ ′ ⎤ Δθ( t) = ⎢ l ∫
Page 221 and 222: Alloy Components Weight Percent, [%
Page 223 and 224: Figure 8: Final results of the ther
Page 225 and 226: Figure 11: Preliminary results of t
Page 227 and 228: In case of the FeNi35, FeNi39 and F
Page 229 and 230: Experimental Methods Compressive st
Page 231 and 232: Type of mixture Water transport pro
Page 233 and 234: Thermal properties The thermal para
Page 235 and 236: Identification of Some Thermophysic
Page 237 and 238: Physical model of the direct proble
Page 239 and 240: 2 ( λ − Bi) sin( λ) − 2λ Bic
Page 241 and 242: To calculate the sensitivity coeffi
Page 243 and 244: symmetry of the specimen when the t
Page 245 and 246: Figure 5: View of experimental setu
Page 247 and 248: During the inverse calculations the
Page 249: temperature dependence for the blac
Page 253 and 254: cross‐planar direction applying s
Page 255 and 256: 3. Thermal diffusivity identificati
Page 257 and 258: Table 2: Effect of the convective h
Page 259 and 260: [2] BODZENTA, J.; BURAKA, B.; NOWAK
Page 261 and 262: doc. Ing. Jiří Vala, CSc. Brno Un
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