부산대학교 도서관

This study tests the using of two types of Fresnel lenses (linear and spot) as a solar concentrator to increase the generation of steam in a system comprising a cylinder to create steam with the addition of a cavity receiver and a glass cover. The experiment was carried out in Karbala (latitude 32° 36' N, longitude 44° 0' E) Iraq. The apparatus comprises a wooden foundation that is 115 * 50 * 17 cm in size and has four wheels that move at the bottom. Two wooden columns, each measuring 105.5 cm in length, are also included. Each one of them can hold six liters of pressure. They allow water to flow into the steam generator for that function. The solar concentrator's reflected or passed energy travels via a cavity receiver before colliding with the absorber tube. The results of the experiment revealed that using the glass cover for the receiver's cavity increased the amount of radiation focused on the steam-generating cylinder as the temperature increased from 66.8 to 80.3 oC with the inclusion of the glass cover. When a spot-type Fresnel lens with a hollow receiver and no glazing was installed, the steam-generating cylinder's temperature rose to 98.7 oC. The usage of the glass cover caused the temperature to rise to 133.3 oC. In the second phase of the experiment, a linear lens was used in place of the Fresnel spot lens. Without the cavity's cover glass, the findings revealed that the temperature and pressure were 57.5 °C (0.15 bar). The temperature and pressure were 69.4 °C and 0.285 bar when the glass cover was used with a linear Fresnel lens. [ABSTRACT FROM AUTHOR]