A slotted waveguide applicator for continuous flow grain drying.

A slotted waveguide antenna was designed and developed with series slots cut on the broad side that constituted a popular means of coupling microwaves with grain for drying. The radiating characteristics of the slotted wave guide antenna mounted in a setup that simulated the coupling to a grain conveying tube were studied at a frequency of 2.45 GHz. The antenna consisted of a WR-340 waveguide made of copper. The effect of the slot inclination angle O, moisture content and the shape of the slots were investigated. The results indicated 55 degrees as an optimum slot angle for slots having a width of 13 mm and a length 58 mm. Slots with a width of 6 mm did not exhibit any regular behavior and the effect of O was not clearly identified.