| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 669784 | International Journal of Thermal Sciences | 2009 | 9 Pages |
An important aim of worldwide research engineering is to identify new industries to introduce solar energy installations for average thermal level.Due to the mechanical and thermal properties of bitumen, such as the 44–49 °C softening point of D80/100 type bitumen, this material can be preheated by using solar thermal installations.The Physics Department of “Politehnica” University of Timisoara designed and studied a laboratory installation for preheating in environmental conditions an amount of 25.1 kg of bitumen up to 55 °C per day.The paper developed a previous original research regarding bitumen preheating by using solar energy. The experimental installation was improved and experimental data were statistically processed. The main improvements were based on:–increasing the amount of incident solar radiation by: (a) reducing the height of the brick walls and replacing them with transparent glass plates; (b) painting the inner faces of the brick walls in white;–cutting down thermal losses by: (a) achievement of the double greenhouse effect in the transparent areas of the installation; (b) change of the brick walls into passive walls. The performances of the installation were improved as follows:–increasing time of the bitumen temperature increased from 7 hours to 8 hours, in the interval 8 am–4 pm;–bitumen maximum temperature increased from 55 to 63.3 °C;–average temperature in bitumen increased from 41.4 to 46.4 °C;–maximum efficiency increased from 12 to 14.4%;–daily average efficiency increased from 6.3 to 7.3%;–maximum difference between the bitumen temperature and environmental one increased from 24 to 32 °C.
