中国医学物理学杂志
中國醫學物理學雜誌
중국의학물이학잡지
CHINESE JOURNAL OF MEDICAL PHYSICS
2009年
6期
1528-1530,1535
,共4页
江楠%王祝盈%陈小林%谢中%蒋文科
江楠%王祝盈%陳小林%謝中%蔣文科
강남%왕축영%진소림%사중%장문과
微波热疗机%辐射器效率%微波功率%定标
微波熱療機%輻射器效率%微波功率%定標
미파열료궤%복사기효솔%미파공솔%정표
microwave hyperthermia apparatus%efficiency of the radiator%microwave power%calibration
目的:针对目前微波热疗机所采用的功率定标方法中没有考虑辐射器的损耗的问题,设计一套测量微波热疗机实际输出功率的装置,提出一种新的对微波热疗机实际输出功率进行定标的方法.方法:利用控制系统控制磁控管阳极电流维持在某一预设值,利用小功率计测量由微波源产生的,经过同轴电缆的微波功率P_(同轴电缆).然后将辐射器接上同轴电缆,使辐射器辐射的微波被实验装置中的水完全吸收.通过测量水的温度变化计算出水吸收的微波能量.利用冷却速率计算实验装置散失的能量,最后由两者能量之和与时间的比例得出辐射器输出的功率P_(辐射器).与此同时,可由P_(同轴电缆)与P_(辐射器)的比值得出辐射器的效率η_(辐射器).结果:微波热疗机通过辐射器输出的实际微波功率与磁控管阳极电流的关系为:P_(辐射器)=2η_(辐射器)1,在不同阳极电流下,得出辐射器的效率为:η_(辐射器)=(34±1)%.结论:从实验结果得知,现行微波热疗机的功率定标方法是有缺陷的,它没有考虑辐射器的转换效率,因此它测量的不是微波热疗机输出的实际微波功率.而采用本文介绍的定标方法可以准确获得微波热疗机的实际输出功率.
目的:針對目前微波熱療機所採用的功率定標方法中沒有攷慮輻射器的損耗的問題,設計一套測量微波熱療機實際輸齣功率的裝置,提齣一種新的對微波熱療機實際輸齣功率進行定標的方法.方法:利用控製繫統控製磁控管暘極電流維持在某一預設值,利用小功率計測量由微波源產生的,經過同軸電纜的微波功率P_(同軸電纜).然後將輻射器接上同軸電纜,使輻射器輻射的微波被實驗裝置中的水完全吸收.通過測量水的溫度變化計算齣水吸收的微波能量.利用冷卻速率計算實驗裝置散失的能量,最後由兩者能量之和與時間的比例得齣輻射器輸齣的功率P_(輻射器).與此同時,可由P_(同軸電纜)與P_(輻射器)的比值得齣輻射器的效率η_(輻射器).結果:微波熱療機通過輻射器輸齣的實際微波功率與磁控管暘極電流的關繫為:P_(輻射器)=2η_(輻射器)1,在不同暘極電流下,得齣輻射器的效率為:η_(輻射器)=(34±1)%.結論:從實驗結果得知,現行微波熱療機的功率定標方法是有缺陷的,它沒有攷慮輻射器的轉換效率,因此它測量的不是微波熱療機輸齣的實際微波功率.而採用本文介紹的定標方法可以準確穫得微波熱療機的實際輸齣功率.
목적:침대목전미파열료궤소채용적공솔정표방법중몰유고필복사기적손모적문제,설계일투측량미파열료궤실제수출공솔적장치,제출일충신적대미파열료궤실제수출공솔진행정표적방법.방법:이용공제계통공제자공관양겁전류유지재모일예설치,이용소공솔계측량유미파원산생적,경과동축전람적미파공솔P_(동축전람).연후장복사기접상동축전람,사복사기복사적미파피실험장치중적수완전흡수.통과측량수적온도변화계산출수흡수적미파능량.이용냉각속솔계산실험장치산실적능량,최후유량자능량지화여시간적비례득출복사기수출적공솔P_(복사기).여차동시,가유P_(동축전람)여P_(복사기)적비치득출복사기적효솔η_(복사기).결과:미파열료궤통과복사기수출적실제미파공솔여자공관양겁전류적관계위:P_(복사기)=2η_(복사기)1,재불동양겁전류하,득출복사기적효솔위:η_(복사기)=(34±1)%.결론:종실험결과득지,현행미파열료궤적공솔정표방법시유결함적,타몰유고필복사기적전환효솔,인차타측량적불시미파열료궤수출적실제미파공솔.이채용본문개소적정표방법가이준학획득미파열료궤적실제수출공솔.
Objective: Nowadays, the power calibration methods of the microwave hyperthermia apparatus doesn't take the power loss of the radiator into account Aiming at this problem, the authors designed an equipment of measuring the actual output power of the microwave hyperthermia apparatus. A new method is proposed for calibration the output microwave power of microwave hyperthermia apparatus. Methods: The magnetron anode current was maintained at a default value by a control system. The microwave power generated by microwave source is coupled firstly to a low-power meter by the coaxial cable to measuring the power going through coaxial cable (P_(coaxial cable)). Then the microwave radiator is connected to the coaxial cable to make the microwave radiated by radiator. The radiator is assembled in the experimental device for the microwave completely absorbed by the water. The absorbed microwave energy of the water is calculated by measuring the water temperature change. The energy loss of the experimental device is calculated using the cooling rate. The output power of the radiator is equal to the ratio of the sum of the two aforementioned energy and the time. And the efficiency of the radiator η_(radiator), is equal to P_(radiator)/P_(coaxial cable) Results: The relationship between the actual output power of the microwave hyperthermia apparatus and the mag- netron anode current is P_(radiator) = 2η_(radiator) I. The efficiency of the radiator is η_(radiator)= (34±1)%. Conclusion: From the experimental results, the current method for calibration output power of microwave hyperthermia apparatus is defective, it dose not consider the conversion efficiency of radiator. Using the calibration method introduced in this paper, wecan accurately deter- mine the actual output power of microwave hyperthermia Apparatus.