Analysis of Heat Flow Data—in situ Thermal Conductivity Measurements

1971 ◽  
Vol 8 (1) ◽  
pp. 1-19 ◽  
Author(s):  
A. E. Beck ◽  
F. M. Anglin ◽  
J. H. Sass
Keyword(s):  
Thermal Conductivity ◽  
Field Experiments ◽  
Contact Layer ◽  
Design Parameters ◽  
Probe Design ◽  
Thermal Mass ◽  
Flow Data ◽  
Conductivity Measurements ◽  
The Many

The electrically heated cylindrical probe has often been used to measure the thermal conductivity of materials which allow the contact layer to be small enough to have negligible thermal resistance and negligible thermal mass. The probe method is not widely used in boreholes, mainly because the increased complexity of the theory required by the boundary conditions encountered in typical field situations makes it difficult to design appropriate probes and to interpret the data.This paper deals with the results of a comprehensive series of laboratory and field experiments, using cased and uncased boreholes, to investigate the importance of various design parameters and to compare the relative merits of the many proposed methods of reducing the data.It has been found that there is a surprising degree of latitude in probe design provided an uncertainty of 10% in conductivity values can be tolerated.

scholarly journals The thermal behavior of rammed earth wall in traditional house in Vojvodina: Thermal mass as a key element for thermal comfort

2018 ◽  
Vol 22 (Suppl. 4) ◽  
pp. 1143-1155
Author(s):  
Vesna Lovec ◽  
Milica Jovanovic-Popovic ◽  
Branislav Zivkovic
Keyword(s):  
Thermal Conductivity ◽  
Thermal Behaviour ◽  
Mass Effect ◽  
High Heat ◽  
Rammed Earth ◽  
Thermal Mass ◽  
Building Stock ◽  
Rammed Earth Wall ◽  
Earth Walls

The conducted research examines the thermal behaviour of the rammed earth walls, which is the basic structural and fa?ade element of traditional Vojvodina house. The traditional rammed earth house represents an important part of the total building stock of Vojvodina. Earth is a locally available, cheap, natural, environmentally friendly building material and has been used extensively for traditional family houses in Vojvodina. It has ecological and ?green? characteristics, which can be assessed as very high quality, and they are of significant importance in the context of sustainable development and striving to reduce energy consumption today. The research examines thermal behaviour of rammed earth wall, including theoretical analysis of: the heat transfer coefficient, U, the thermal resistance, R, and thermal conductivity, ?. One of the basic elements of thermal behaviour, the thermal mass, has been analyzed both theoretically and by measuring in situ. The in situ measurements were conducted on the traditional house in Vojvodina by measuring inside and outside surface wall and air temperature in summer. Analyses of rammed earth wall thermal performances have shown that the wall has low thermal conductivity, high heat capacity and significant thermal mass effect which is the key element enabling thermal stability. The research indicates rather good thermal properties of the rammed earth walls. Potential of rammed earth wall in Vojvodina should be an issue of further analysis, although the possibility of improvement of existing facilities to meet current standards in terms of energy efficiency should be considered.

scholarly journals In situ thermal conductivity measurements of Titan's lower atmosphere

Icarus ◽  
2008 ◽  
Vol 197 (2) ◽  
pp. 579-584 ◽  
Author(s):  
B. Hathi ◽  
A.J. Ball ◽  
M. Banaszkiewicz ◽  
P.M. Daniell ◽  
J.R.C. Garry ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Lower Atmosphere ◽  
Conductivity Measurements

In Situ Thermal Conductivity Measurements of Building Materials with a Thermal Probe

2010 ◽  
Vol 38 (3) ◽  
pp. 102636
Author(s):  
M. R. Mitchell ◽  
R. E. Link ◽  
B. Pilkington ◽  
S. Goodhew ◽  
P. deWilde
Keyword(s):  
Thermal Conductivity ◽  
Building Materials ◽  
Conductivity Measurements ◽  
Thermal Probe

scholarly journals Evaluation of the Thermal Comfort and Energy Demand in a Building with Rammed Earth Walls in Spain: Influence of the Use of In Situ Measured Thermal Conductivity and Estimated Values

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 635
Author(s):  
Miguel Ángel Mellado Mascaraque ◽  
Francisco Javier Castilla Pascual ◽  
Víctor Pérez Andreu ◽  
Guillermo Adrián Gosalbo Guenot
Keyword(s):  
Thermal Conductivity ◽  
Thermal Comfort ◽  
Energy Demand ◽  
Winter Period ◽  
Rammed Earth ◽  
Thermal Mass ◽  
Nominal Data ◽  
K Value ◽  
Earth Walls

This paper describes the influence of thermal parameters—conductivity, transmittance, and thermal mass—in the estimation of comfort and energy demand of a building with rammed earth walls, and consequently, the compliance with standards. It is known that nominal design data does not match in situ measured values, especially in traditionally constructed buildings. We have therefore monitored a room in a building with rammed earth walls, designed a computerised model, and compared four different alternatives where we have changed the value for the thermal conductivity (in situ vs. estimated) and the consideration of thermal mass. When we then analyse the compliance with the Spanish energy saving code, using measured values would result in lower differences with the standards’ limits and even comply with the global thermal transmittance (K-value) requirement. This would mean a more realistic approach to the restoration of traditional buildings leading to the use of thinner and more suitable insulation and retrofitting systems, encouraging the use of rammed earth in new buildings, and therefore reducing the carbon footprint due to materials used in construction. Results show that the building model that uses in situ values and considers thermal mass (S1) is closer to reality when assessing thermal comfort. Finally, using nominal data would result in requiring 43% more energy in the selected winter period and 102% more energy in the selected summer period to keep the same comfort conditions as in the alternative where measured values are used.

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