Geometrical and physical properties of aggregatum onion bulbs were studied were studied for design of equipment for processing, sorting, transportation and heat transfer processes. The equatorial diameter, polar diameter, thickness, Dgm, Dam, Af.s and As.c of the fresh and three months stored CO 4 cultivar were determined. Surface area ranged between 7.0 to 30.5 cm2 for fresh onion and three months stored onions. Spherical shapes of bulbs were indicated by values of shape index and sphericity. The roundness values were 0.87 ± 0.04 and 0.84 ±0.08 for fresh and stored onion samples respectively. Mass, volume, true density and bulk density were decreased whereas the porosity was increased from the fresh and three months stored onion bulbs. Geometrical and physical properties of the CO 4 onion varieties are the essential parameters for all the properties such as mechanical properties, thermal properties and quality analysis. This data could be used for designing of processing equipments, storage structures and transport.
