Research on Food Heater Based on Rotating Electromagnetic Theory

　　Research on Food Heater Based on Rotating Electromagnetic Theory
　　With the rapid development of economy、the continuous variation of population structure and the innovation of economic structure, energy consumption is rising rapidly and energy security issue becomes the focus of energy development. Electric heating technique which can prevent the pollution of the environment, is recognized widely. Therefore, electrothermics is developed to a cross-subject which includes many subjects such as electrical engineering, pyrology and material science. Based on the flameless electromagnetic heater(Patent Number is 200410044061), magnetic materials this paper represents the foundational research on its calefaction parts that food heater.
　　Firstly, the thesis introduced the variety and application of electric heating, and showed the new concept that dynamic electromagnetic induction; The thesis introduced the heating technology in the war in china and abroad, and analysed the advantage and the disadvantage of these heating ways.Secondly, the thesis refered the structure of the food heater and its operation principle, and established the equivalent magnetic circuit model. Then from the point of view of the reverse problem of temperature rise of electric machines, thesis established the exothermic model of the heater based on electromagnetic field and experiential formulae.Thirdly, the 2D finite element analysis model of the heater what had the similar structure like the permanent-magnet synchronous motor was founded in the thesis. The thesis analysed the distributing rules of static air gap field and the distributing instances of leakage flux, and assessed the change of air gap field altering the size of air gap field and the direction of magnetism. Then from the point of reduced leakage flux, an optimizational structure was brought forward in the thesis. Compared the air gap field of the improved and primary structure. When the rotating http://www.999magnet.com speed was invariable, the heating powers of the heater were analyzed. The values of the heat powers in different rotating speeds and their changing regularity versus rotating speed were given in the thesis. The thesis assessed the optimizational structure from the point of heating power and torque characteristic, and verifies theoretically that the improved structure had an advantage over the primary one.At last, the experiment equipment was designed. The temperature rise curve of the heater was measured, and it was compared with the simulation results.