Thermal conductivity table of building materials

Thermal conductivity of building materials, their density and heat capacity

An extensive table of thermal conductivity of building materials, as well as density and specific heat capacity of materials in a dry state at atmospheric pressure and a temperature of 20 ... 50 ° C (unless another temperature is indicated) is given. Values ​​given for over 400 materials!

Attention should be paid to the value of thermal conductivity of building materials in the table, since this characteristic, along with their density, is the most important. Especially thermal conductivity is important for building materials used as thermal insulation for thermal insulation of building structures.

The thermal conductivity of building materials significantly depends on their porosity and density. The lower the density, the lower the thermal conductivity of the material., therefore, low thermal conductivity is characteristic of porous and light materials (you can also find the density values ​​of building materials, metals and alloys, products and other substances in the detailed density table).

For example, in our table of thermal conductivity of materials and heaters, the following building materials with a low coefficient of thermal conductivity can be distinguished - this is airgel (from 0.014 W / (m deg)), glass wool, expanded polystyrene foam and expanded rubber (from 0.03 W / (m · deg)), MBOR insulation (from 0.038 W / (m · deg)), aerated concrete and foam concrete (from 0.08 W / (m · deg)).
Thermal conductivity of building materials - table

Sources: 1. Physical quantities. Directory. A.P. Babichev, N.A. Babushkina, A.M. Bratkovsky and others; Ed. I.S. Grigorieva, E.Z. Meilikhova. - M.: Energoatomizdat, 1991 .-- 1232 p. 2. Eremkin A.I., Queen T.I. Thermal regime of buildings: Tutorial. - M .: Publishing house ACB, 2000 - 368 p. 3. Kirillov P.L., Bogoslovskaya G.P. Heat transfer in nuclear power plants: Textbook for universities. - M .: Energoatomizdat, 2000 .-- 456 p .: ill. 4. Mikheev M.A., Mikheeva I.M. Basics of heat transfer. 5. Franchuk A.U. Tables of thermal performance of building materials, Moscow: Research Institute of Construction Physics, 1969 - 142 p. 6.V. Blazi. Designer handbook. Building physics. M .: Tekhnosfera, 2004. 7. Construction heat engineering SNiP II-3-79. Ministry of Construction of Russia - Moscow 1995. 8. Novichenok N.L., Shulman Z.P. Thermophysical properties of polymers. Minsk, "Science and Technology" 1971. - 120 p. 9. Isachenko V.P., Osipova V.A., Sukomel A.S. Heat transfer. Textbook for universities, ed. 3rd, rev. and add. - M .: "Energy", 1975. - 488 p.

How to calculate thermal conductivity according to Fourier's law

In a given thermal regime, the flux density during heat transfer is directly proportional to the vector of the maximum temperature increase, the parameters of which change from one section to another, and modulo with the same rate of temperature increase in the direction of the vector:

q → = - ϰ х grad х (T), where:

• q → is the direction of density of an object that transfers heat, or the volume of heat flux that flows through the site for a given time unit through a certain area, perpendicular to all axes;
• ϰ - specific coefficient of thermal conductivity of the material;
• T is the temperature of the material.

Heat transfer in a nonequilibrium thermodynamic system
The sign "-" in the formula before "ϰ" indicates that the heat moves in the opposite direction from the vector grad х (T) / - in the direction of decreasing the temperature of the object. This formula reflects Fourier's law. In an integral expression, the heat transfer coefficient according to Fourier's law will look like the formula:

• P = - ϰ x S x ΔT / l, expressed in (W / (m • K) x (m2 • K) / m = W / (m • K) x (m • K) = W), where:
• P is the total power of heat transfer losses;
• S - cross-section of the object;
• ΔT is the temperature difference at the joints of the sides of the object;
• l - the distance between the joints of the sides of the object - the length of the figure.

Relationship between the thermal conductivity coefficient and the electrical conductivity of materials