Research Papers: Conduction

Determination of the Thermal Conductivity in Adobe With Several Models

[+] Author and Article Information
P. Mosquera

e-mail: pablomosquera@terra.com

J. Cid-Falceto

Research group PADOC (Patrimony, Landscape,
Graphic Documentation and Agroforestry
Esc. Técnica,
Superior de Ingenieros Agrónomos,
Universidad Politécnica de Madrid, s/n
28040 Madrid, Spain

F. Marcos

Thermodynamics, Engines and Forestry Machinery,
Esc. Técnica,
Superior de Ingenieros de Montes,
Universidad Politécnica de Madrid,
Ciudad Universitaria,
s/n. 28040 Madrid, Spain

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received March 6, 2013; final manuscript received August 5, 2013; published online November 28, 2013. Assoc. Editor: Oronzio Manca.

J. Heat Transfer 136(3), 031303 (Nov 28, 2013) (10 pages) Paper No: HT-13-1116; doi: 10.1115/1.4025560 History: Received March 06, 2013; Revised August 05, 2013

The thermal conductivity of the earth materials conditions their ability as thermal isolator and its heating capacity, which has a direct impact on the energy consumption of the buildings built with these materials. Two original mathematical models have been developed (models MA-1 and MA-2) to calculate the effective thermal conductivity (λE) of adobes and their results have been compared with other models already known for other materials and with experimental measures done on adobes. The model MA-1 starts from the electric analogy of the transmission of heat in series and in parallel. The model MA-2 is obtained with a regression curve from experimental and literature values of λE in adobes. The λE in adobes has been measured by the thermal needle probe (TNP) procedure using 10 min as the measuring time. For dry adobes, with average environmental conditions of 19 °C and 41% of relative moisture, the values of λE measured were 0.80 W/(m·K) ± 10%. For natural hygroscopic moisture of 1.67% in the same environmental conditions, a λE of 0.90 W/(m·K) ± 10% was measured. Only five of the 18 models analyzed adjust to the values experimentally measured, and their precision depends on the values of λ of the components, which are obtained from the literature. Of the proposed models, the MA-1 fits for the values of the dry and wet material and with some determined values of the literature. The model MA-2 fits in all cases since it does not depend on the values of the literature but on the density of the material and its moisture content.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Fig. 1

X-ray diffractometry

Grahic Jump Location
Fig. 2

Measurement device of thermal conductivity

Grahic Jump Location
Fig. 3

Diagram of the needle in contact with the porous material

Grahic Jump Location
Fig. 4

Evolution of the temperature during the measurement time

Grahic Jump Location
Fig. 5

Sketch for components in series

Grahic Jump Location
Fig. 6

Sketch for components in parallel

Grahic Jump Location
Fig. 8

MA-2 model: thermal conductivity as a function of the density




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In