• Z. Shu, M.J. Li, L.G. Shen, Y. Sun, X.C. Wang, W. Zhao
  USTC/PMPI, Hefei, Anhui
• Y.J. Pei
  USTC/NSRL, Hefei, Anhui

Funding: "Collinear Load for Accelerators and R&D on High Power Microwave Absorbed Material" No.10775128 From National Natural Science Foundation of China

Thermal deformation caused by Non-uniform temperature distribution in disk-loaded waveguide will affect the resonant frequency of LINAC deeply. Formerly, researchers evaluated it by experiments or experience and gave their conclusion roughly and linearly. A new approach of integration of multi-disciplinary is adopted to study the relationship more accurately. After loading the loss RF power on the accelerator tube wall, the thermal deformation is calculated in software I-DEAS, and a deformed finite element model is obtained. Then nodes on inner surfaces of the cavities were extracted and sort by a customized program. According to these nodes, a new solid model is reconstructed with a self developed 3D reconstruction technology in ANSYS. B-Spline interpolation technique is used to fit a group of curves first, and then to reconstruct NURBS surfaces. The final reconstructed deformed solid model, obtained by closing the surfaces, can be exported in IGES format which is used to recalculate the resonant frequency in Microwave Studio again. The error of the reconstruction can be controlled within 3 micrometers. The resonant frequency change of every cavity can be accurately calculated.

Parietti L, etc., Thermal structural analysis and frequency shift **
Zhou, Zu-Sheng,etc. Thermal structural analysis and test **

• X.D. He, S. Dong, Y.J. Pei, C.-F. Wu
  USTC/NSRL, Hefei, Anhui

Funding: the National Nature Science Foundation of China, Grant No. 10375060, 10375061 and 10675116

One of the major concerns in the development of hybrid dielectric-iris-loaded structure is the performance of the used dielectric. The previous dielectric is machinable but the loss tangent is slightly high. So we adopt the new dielectric (Mg-Ca-Ti-O) with loss tangent of about 2·10^-4. Because of its high hardness and brittleness, the machining technology and methods are attempted. In this paper, we present a new design of the structure. The model cavities and the coupler for this structure with the new dielectric are investigated experimentally. The experiment results are accorded with the simulated results. In the end, the amplitude and phase shift of the electric field and R/Q of this structure at the operation frequency are even got by a bead-pull experiment.