Regular Article

Periodical metal cylinders for improving heating uniformity of small batch materials in microwave applicators with rotating turntables

¹ National and Local Joint Engineering Laboratory of Intelligent Transmission and Control Technology (Chongqing), Southwest University, Chongqing 400715, PR China
² College of Electronics and Information Engineering, Southwest University, Chongqing 400715, PR China
³ College of Electronics and Information Engineering, West China Normal University, Nanchong 637002, PR China
⁴ College of Electronics and Information Engineering, Sichuan University, Chengdu 610029, PR China

^* e-mail: lyh2006@swu.edu.cn

Received: 4 February 2018
Received in final form: 6 May 2018
Accepted: 10 September 2018
Published online: 26 October 2018

Abstract

Microwave applicators with rotating turntables have been widely applied in many fields, but the heating non-uniformity still limits the further applications. Specifically, when microwave applicators are used to process small batch materials, materials have to be away from the center of rotating turntables, where the problem of heating non-uniformity is more prominent. In order to overcome this difficulty, this paper presents a novel periodical metal cylinder structure to improve the heating uniformity for microwave applicators. With the proposed periodical metal cylinders being placed beneath rotating turntables, electromagnetic fields can be well adjusted, thus improving the heating uniformity. To demonstrate the heating uniformity with the proposed structure, the heating process of the arrays of two and three potato slices in a practical microwave applicator is simulated by the finite element method, respectively. The results show that both the heating uniformity of the two and three potato slices can be improved, which is validated by experiments. Furthermore, the results show that the temperature similarity among the processed potato slices with the proposed structure is better than that without the proposed structure.