Electromagnetic Analysis of Coaxial Gyrotron Cavity With the Inner Conductor Having Corrugations of an Arbitrary Shape

Abstract

Abstract-The mathematical approach for the calculation of the membrane functions of a coaxial gyrotron cavity with an arbitrary corrugated inner rod is proposed. It is utilized mainly for two aims. First, it is shown that for typical parameters of the coaxial gyrotron cavity with the corrugated inner conductor the shape of corrugations only slightly influences the eigenvalues of competing eigen-modes. However, it can significantly influence the density of ohmic losses in the inner conductor. In particular, it is shown that the density of ohmic losses can be reduced almost twice by the proper choice of the corrugation shape. Second, it is shown that the usual idealizations of the corrugated surface of the inner conductor (the surface with rectangular grooves, having rounded edges, is approximated by a surface with wedged groves that have sharp edges) are correct. The physical interpretation of the obtained results and their practical meaning are discussed.

Improved theory of energy losses in corrugated inner conductor of coaxial gyrotron cavity

“…On the other hand, theoretical results also can contain errors due to idealization of corrugation geometry or simplification of physical model. According to [9] geometrical idealizations of corrugarions hardly can be a reason for such a discrepancy. However, the physical model used in all previous research raises some questions.…”

“…One of important aspects significantly influencing design of coaxial gyrotron cavity is Ohmic losses in the corrugated inner conductor. Calculations based on different full wave approaches (see, for example, [9][10][11] and references therein) do not correlate with experimental measurements [12], showing 3-4 times lower losses. Reasons of such a large discrepancy are still unclear.…”

A 2.45 GHZ Reentarnt Coaxial Cavity for Liguid Sterilization Based on Non-Thermal Microwave Effect

“…The coaxial cavity structure with high field intensity has been researched [16,17], but there are few reports about using this structure to sterilize for liquid, because the electric field is too high and because the dielectric constants are much different from air. Here we report a modified microwave coaxial cavity resonator.…”

Propagation Characteristics of a Variant of Disc-Loaded Circular Waveguide

“…In these devices, one may see the periodic beam-wave interaction structures holding either azimuthal or axial periodicity [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]. The azimuthal periodicity in interaction structure may be seen, for example: in travelling-wave magnetrons [14] for π-mode operation, in gyrotrons [21][22][23][24] for mode rarefaction, in conventional helixTWTs [17] for broadbanding, in gyro-travelling wave tubes (gyroTWTs) [25,26] for higher interaction impedance and, in turn, for higher device-gain. The axial periodicity in interaction structure may be seen, for example, in conventional helix-TWT [17] for higher device-gain, in coupled-cavity TWT [17] for getting fundamentalmode backward-wave characteristics, and in gyro-TWT [27][28][29][30][31][32][33][34][35][36][37][38][39] for broadbanding.…”

“…and even in the vacuum electronic devices, such as, linear/particle accelerators [11,12], backward-wave oscillators (BWOs) [13], magnetrons [14], coupledcavity and helix travelling-wave tubes (TWTs) [15][16][17][18][19], cyclotron masers [20,21], gyrotron sources [21][22][23][24] and amplifiers [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39], etc.. In these devices, one may see the periodic beam-wave interaction structures holding either azimuthal or axial periodicity [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]…”