Vol. 7, Issue 5, Part C (2025)

The solar dryer is designed to prepare mango leather by reducing the moisture content of mango pulp to a range of 12-20%, which effectively preserves the product by inhibiting microbiological growth. The dryer operates by heating air within the chamber to facilitate moisture extraction from the mango pulp placed on trays. The drying chamber of the solar dryer is constructed using an 18-gauge galvanized iron sheet with dimensions of 90 × 30 × 30 cm. The sheet has a thickness of 2 mm, and the interior is coated with a black nano-coating to enhance heat absorption. To improve the reflection of solar radiation, aluminium foils are arranged inside the chamber. The top of the drying chamber is covered with a 4 mm thick transparent glass panel set at a 45° inclination from the rear to the front, maximizing solar radiation incidence. The exhaust vent is positioned at the top right of the chamber, at a height of 10 cm from the tray surface, to facilitate moisture release. The tray, made of 16-gauge stainless steel with dimensions of 88 × 28 cm, is divided into two sections to simultaneously dry different formulations of mango pulp. The tray is positioned inside the chamber to prevent direct sunlight exposure, preserving the nutritive value and flavor of the mango leather. The entire solar dryer assembly is mounted on a supporting stand made from a 2×2 cm square rod with a height of 45 cm. The drying process operates within a temperature range of 45-65°C, with the solar dryer designed to function efficiently at full load conditions. The average heat requirement for drying under dry day conditions is approximately 6601.7 kJ. This design ensures effective solar energy utilization while maintaining the quality of the dried mango product.