Electronic Theses and Dissertation

The research results indicate that the total daily radiation was 13.4418 MJ/m² on the first day and 19.9722 MJ/m² on the second day. The average solar irradiation was 461 W/m² on the first day, increasing to 666 W/m² on the second day. The standard deviation was 315.24 W/m² on the first day and 217.85 W/m² on the second day. Asphalt was used as the heat storage medium, with the average tube wall temperature ranging from 40.7°C to 47.9°C. Energy calculations show that the total useful thermal energy (Qout) produced by the collector increased from 1.0879 MJ on the first day to 1.4505 MJ on the second day. This increase corresponds to the rise in solar radiation energy received by the collector (Qin), which went from 36.5617 MJ on the first day to 54.3244 MJ on the second day. The solar collector efficiency decreased from 2.98% on the first day to 2.67% on the second day. Nevertheless, the collector remained capable of converting solar energy into thermal energy, while the asphalt medium helped maintain the temperature by storing and gradually releasing heat. An average airflow of 2.85 m/s also facilitated the heat transfer process to the drying chamber.

The research results indicate that the total daily radiation was 13.4418 MJ/m² on the first day and 19.9722 MJ/m² on the second day. The average solar irradiation was 461 W/m² on the first day, increasing to 666 W/m² on the second day. The standard deviation was 315.24 W/m² on the first day and 217.85 W/m² on the second day. Asphalt was used as the heat storage medium, with the average tube wall temperature ranging from 40.7°C to 47.9°C. Energy calculations show that the total useful thermal energy (Qout) produced by the collector increased from 1.0879 MJ on the first day to 1.4505 MJ on the second day. This increase corresponds to the rise in solar radiation energy received by the collector (Qin), which went from 36.5617 MJ on the first day to 54.3244 MJ on the second day. The solar collector efficiency decreased from 2.98% on the first day to 2.67% on the second day. Nevertheless, the collector remained capable of converting solar energy into thermal energy, while the asphalt medium helped maintain the temperature by storing and gradually releasing heat. An average airflow of 2.85 m/s also facilitated the heat transfer process to the drying chamber.