Analysis And Application Of Microwave Characteristics Of Loose Mixture Materials

Loose mixture,is a state of accumulation of powder composed of two or more substances when free filled in a fixed container.Based on the requirement of item “Poor oil materials of high power microwave treatment”,analyzing the microwave characteristics of oil sand samples in the heating vessel,summarizing the methods of improving the efficiency of microwave selective heating.This paper choose mature TM0n0 mode cylindrical cavity to measure complex permittivity of materials,apply Lichtenecker logarithmic mixture formula to calculate equivalent complex permittivity of materials in the heating vessel and a prototype of heating furnace is designed to meet the industrial demand.At room temperature,a simple measurement of port reflection is obtained,which is in good agreement with the theoretical results.Specific research results are as follows:(1)In this paper,first analyzing physical properties of the poor oil materials,and summarizing characteristics of “loose mixture”,choosing an effective medium theory as focus in a series of equivalence theory;Lichtenecker logarithmic mixture formula obtained theoretical proof,and is separated from the semi empirical formula.Using the deriving of this formula to calculate equivalent complex permittivity of uniform mixing of materials and air;Secondly,the relationship between the logarithmic formula and the other two common formulas is derived by using the CM factor,explicit logarithmic formula has obvious advantages in practical application.(2)Secondly,according to the dielectric properties of the loose mixture material,this paper presents a method of measuring the complex permittivity by using the cavity perturbation method,making the test system of TM0n0 mode cylindrical resonant cavity,and a simple experimental platform can be used for heating;using quartz crystal,PTFE and water to calibrate the test algorithm,at room temperature,10 oil sands samples with different water content and oil content in each of the two groups were tested,analyzing the measure results we found: The oil content has no obvious influence on the test results,but the water content is the key factor affecting the microwave loss.(3)Finally,describing the advantages of microwave heating technology,to meet industrial demand,aiming at 915 MHz industrial microwave source,this paper presents an open-ended coaxial resonator system as a heating container,a prototype is simulated and processed,at room temperature,the oil sands samples with the volume fraction of 0.4,0.5,0.6 and 0.7 were filled,measuring port voltage in Bobbi,compared with the theoretical value we found: The actual reflection of coaxial cavity is larger than the theoretical value,but the trend is consistent,it is proved that the logarithmic formula theory is applicable,The actual operation is not ideal,and finally analyzed the error terms.