新型開口式共振腔之數值模擬與分析

Abstract

本論文內容的探討主要圍繞著不同型式的開口式共振腔，開口式共振腔普遍應用在研究磁旋調速管(gyroklystron)、磁旋管(gyrotron)以及磁旋振盪管(gyromonotron oscillator)當中。開口式共振腔與閉口式共振腔的差別在於前者沒有明確的邊界條件，後者有明確的邊界條件，導致前者並無解析解後者有解析解，因此我們運用程式做數值模擬，從中了解物理的現象及意義。 本文先從時域和頻域理論的基礎模型出發，介紹其數學理論與所使用的邊界條件。在時域基礎模型中，探討對共振頻率以及品質因子的影響因素為何，接著介紹在頻域基礎模型中所使用的兩種量測方法，並比較品質因子在時域基礎模型與頻域基礎模型的差異。最後嘗試新的結構，對其數值模擬結果，並給予合理的物理解釋。

The main discussions of the thesis around different open cavities, Open cavities are commonly used in gyroklystron, gyrotron and gyromonotron oscillator. The differences between open cavities and enclosed cavities are the former lack of a well-defined geometrical boundary and the later has a well-defined boundary. Under this condition causes, the former has an analytical solution and the later hasn’t an analytical solution. Hence, we understand its physical property and phenomenon by numerical simulation. This content begins with basic theorem for time-domain and spectral-domain model. Then, we will introduce the math theorem and boundary conditions in our numerical computation. In the time-domain model, we will discuss what impact resonant frequency and quality factor. In the spectral-domain model, we will introduce two measurement methods. Then, we compare the differences in resonant frequency and quality factor between time-domain and spectral-domain model. Finally, we try to simulation new structures and give an appropriate physical explanation for the results.