Trend Diagrams for Sustainable Generalization of Direct Solar Dryers for Agricultural Products

Abstract

A group of regularities of solar drying is given, as a part of an integral approach in solar direct dryers. These are visualized as Mean Efficiency- Specific cost Diagrams, with constructive elements and changes recommended to make this activity more effective integrally. Diagrams are applied to design of solar direct dryers with natural or forced convection of diverse agricultural products as roots, vegetables, fruits, grains and wood. Diagrams were validated for usual rank of efficiencies and products, registered in solar drying in dryers type cabinet, cover and house in tropical conditions. Are useful for design and exploitation of dryers, and for theoretical and practical comprehension of solar drying processes like a system.