Temperature Controlled Combined Microwave-Convection Drying

Abstract

Many materials that are dried have an imposed temperature constraint to ensure product quality is maintained. The paper presents experimental results of combined microwave-convection drying of polyurethane foam at 60°C. It is shown that product temperatures can be controlled by cycling the microwave source on and off. Much reduced drying times are achieved compared to pure convection drying. Comparisons of drying efficiencies show that the combined system should have higher thermal efficiencies than a pure convection system for low product temperature constraints.