Table of Contents
ISRN Renewable Energy
Volume 2012, Article ID 194359, 9 pages
Research Article

Performance Investigation of a Chimney-Dependent Solar Crop Dryer for Different Inlet Areas with a Fixed Outlet Area

1Mechanical Engineering Department, Kumasi Polytechnic, P.O. Box 854, Kumasi, Ghana
2Agricultural Engineering Department, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana

Received 18 September 2012; Accepted 9 October 2012

Academic Editors: E. R. Bandala, F. E. Little, O. Ozgener, and K. Sumathy

Copyright © 2012 J. K. Afriyie and A. Bart-Plange. 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.


The paper describes the performance of a direct-mode solar crop dryer with a solar chimney. Tests were performed for three differently inclined drying-chamber roofs, each with three inlet areas for a given exit area. Cassava was used as the test crop. The results show that the increase in the inlet area for a given exit area can improve the ventilation in the dryer. However, this does not necessarily improve the drying performance of the direct-mode dryer. A wide inlet area for a given exit area can only improve the drying performance of the direct-mode dryer in a geographical location of low relative humidity. It is therefore not advisable to just copy the design of a direct-mode dryer from one location to another without regard to the ambient relative humidity. The designer and builder of the dryer must consider the relative humidity as a prime factor in the design and construction of direct-mode dryers, which are highly sensitive to the ambient relative humidity.