Review Paper on Diffierent Types of Solar Dryer

Abstract

One of the most appealing and economical uses of solar energy is drying agricultural goods. With differing degrees of technical performance, a multitude of solar dryer types have been devised and developed across the globe. In general, solar dryers come in four different varieties: (1) direct solar dryers, (2) indirect solar dryers, (3) mixed-mode dryers, and (4) hybrid solar dryers. The product being dried, as well as technical and financial concerns, are reviewed in this paper together with other solar dryer kinds. Technically speaking, integrated storage, high efficiency, compact collector design, and long-life drying systems are the main focuses in the development of solar-assisted drying systems for vegetables. There exist alternative systems to air-based solar collectors. By using a water-to-air heat exchanger, water-based collectors are another option. A water-to-air heat exchanger can be used to push hot air used for drying agricultural products to pass through it. As part of the solar drying system, the hot water tank stores heat.

Introduction

I. INTRODUCTION

Food items that are dried usually last longer, including pickles, chillies, amlas, seafood, fruits, and spices. Food goods that have been dried are free of moisture and do not harbor bacteria, yeast, or other microorganisms that could cause moisture-related responses. Less weight and volume means less time and money spent on (i) packaging, (ii) storing, and (iii) transporting the food items. This is only one of the many advantages of drying. Food items are also more environmentally friendly after they have been dried.

A. Solar Dryer

Fruits, vegetables, and crops are dried using solar dryers to remove moisture. The solar dryer is comprised of a box constructed from readily available and reasonably priced materials like as plywood, cement, galvanized iron, and brick. Transparent single- and double-layered sheets cover the dryer's upper surface.

B. Types Of Solar Dryer

The main classification criteria for solar-energy drying systems are their modes of heating and how they use solar heat. They can be broadly divided into two categories:

There are three methods of drying: (i) sun exposure, (ii) direct drying, and (iii) indirect drying when solar radiation is present. The process of gathering solar energy and converting it into usable thermal energy determines how these modes operate in general.

Conclusion

For several crops, solar dryness has shown to be advantageous both commercially and technically. Nonetheless, a big number of dryers must be developed so that farmers can be drawn in for a variety of products all year round. It\'s crucial to maintain temperature and relative humidity, protect against UV rays, dust, insects, mold, and other contaminant sources, and enhance product quality. Similar to this, sunshine items should be stored according to the crop; if the packaging is optimized, a long shelf life is needed.

References

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Copyright

Copyright © 2024 Jitendra Kumar Gautam, Pankaj Verma. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.