scholarly journals Estimation of the effective thermal conductivity of rocks in situ by cuttings. Part 1. Development of a rapid measurement method for the effective thermal conductivity of cuttings-water mixture beds at high temperatures and pressures.

1989 ◽  
Vol 54 (2) ◽  
pp. 111-121 ◽  
Author(s):  
Hiroshi KIYOHASHI ◽  
Toshiyuki WATANABE ◽  
Munesuke KYO ◽  
Shozo TANAKA
Keyword(s):  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
High Temperatures ◽  
Measurement Method ◽  
Water Mixture ◽  
Rapid Measurement

scholarly journals Improvement of Phase Change Materials (PCM) Used for Solar Process Heat Applications

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1260
Author(s):  
Cristina Prieto ◽  
Anton Lopez-Roman ◽  
Noelia Martínez ◽  
Josep M. Morera ◽  
Luisa F. Cabeza
Keyword(s):  
Thermal Conductivity ◽  
Solar Energy ◽  
Phase Change ◽  
Effective Thermal Conductivity ◽  
High Temperatures ◽  
Phase Change Materials ◽  
Material Selection ◽  
Inert Atmosphere ◽  
Enhancement Effect ◽  
Process Heat

The high intermittency of solar energy is still a challenge yet to be overcome. The use of thermal storage has proven to be a good option, with phase change materials (PCM) as very promising candidates. Nevertheless, PCM compounds have typically poor thermal conductivity, reducing their attractiveness for commercial uses. This paper demonstrates the viability of increasing the PCM effective thermal conductivity to industrial required values (around 4 W/m·K) by using metal wool infiltrated into the resin under vacuum conditions. To achieve this result, the authors used an inert resin, decoupling the specific PCM material selection from the enhancement effect of the metal wools. To ensure proper behavior of the metal wool under standard industrial environments at a broad range of temperatures, a set of analyses were performed at high temperatures and an inert atmosphere, presenting a thorough analysis of the obtained results.

scholarly journals Modeling the effective thermal conductivity of hollow bricks at high temperatures

2021 ◽  
Vol 309 ◽  
pp. 125066
Author(s):  
Mario Pichler ◽  
Bahram Haddadi ◽  
Christian Jordan ◽  
Michael Harasek
Keyword(s):  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
High Temperatures ◽  
Hollow Bricks

An Experimental Evaluation of the Effective Thermal Conductivities of Packed Beds at High Temperatures

1994 ◽  
Vol 116 (4) ◽  
pp. 829-837 ◽  
Author(s):  
K. Nasr ◽  
R. Viskanta ◽  
S. Ramadhyani
Keyword(s):  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
High Temperatures ◽  
Radiation Heat Transfer ◽  
Particle Diameter ◽  
Spherical Particles ◽  
Packed Beds ◽  
Packing Materials ◽  
Bed Temperature ◽  
Thermal Conductivities

Combined conduction and radiation heat transfer in packed beds of spherical particles was investigated. Three different packing materials (alumina, aluminum, and glass) of various particle diameters (2.5 to 13.5 mm) were tested. Internal bed temperature profiles and corresponding effective thermal conductivities were measured under steady-state conditions for a temperature range between 350 K and 1300 K. The effects of particle diameter and local bed temperature were examined. It was found that higher effective thermal conductivities were obtained with larger particles and higher thermal conductivity packing materials. The measured values for the effective thermal conductivity were compared against the predictions of two commonly used models, the Kunii–Smith and the Zehner–Bauer–Schlu¨nder models. Both models performed well at high temperatures but were found to overpredict the effective thermal conductivity at low temperatures. An attempt was made to quantify the relative contributions of conduction and radiation. Applying the diffusion approximation, the radiative conductivity was formulated, normalized, and compared with the findings of other investigators.

Sign in / Sign up

Export Citation Format

Share Document