Author: Corsaletti, J.C.
Paper Title Page
TUPC14 Copper Braid Heat Conductors for Sirius Cryogenic X-Ray Optics 207
 
  • F.R. Lena, G.V. Claudiano, J.C. Corsaletti, R.R. Geraldes, D.Y. Kakizaki, R.L. Parise, M. Saveri Silva, M.S. Souza, L.M. Volpe
    LNLS, Campinas, Brazil
 
  Funding: Ministry of Science, Technology and Innovation (MCTI)
The low emittance and high photon flux beam present at the 4th-generation Sirius synchrotron light source beamlines result in high energy densities and high heat loads at some specific X-ray optics such as monochromators and white beam mirrors. This challenges the design of such systems since the introduction of thermal stresses may lead to optical surface deformation and beam degradation. Thus, to keep the systems within acceptable deformations some of the optical elements are cryogenically cooled. However, this poses the requirements of decoupling the thermal sinks (cryostats) from the optics and the mechanisms to maintain their desired degrees of freedom for alignment and dynamic operation. In this context we present the development of low-stiffness copper-braid-based heat conductors, summarizing the motivation and main aspects regarding their fabrication and application at the beamlines.
 
poster icon Poster TUPC14 [1.783 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2020-TUPC14  
About • paper received ※ 28 July 2021       paper accepted ※ 19 October 2021       issue date ※ 30 October 2021  
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WEPC07 Thermal Model Validation for the Cryogenic Mirror Systems for Sirius/LNLS 320
 
  • L.M. Volpe, J.C. Corsaletti, B.A. Francisco, R.R. Geraldes, M.S. Silva
    LNLS, Campinas, Brazil
 
  Funding: Ministry of Science, Technology and Innovation (MCTI)
One of the challenges of fourth-generation synchrotron light sources as Sirius at the Brazilian Synchrotron Light Laboratory (LNLS) is the high power density that may affect the beamline optical elements by causing figure deformations that deteriorate the quality of the beam. Indeed, surface specifications for height errors of X-ray mirrors are often within a few nanometers. To deal with these thermal management challenges, thermo-mechanical designs based on cryogenic silicon have been developed, taking advantage of its high thermal conductance and low thermal expansion in temperatures of about 125 K. A liquid nitrogen (LN2) cryostat connected to the optics by copper braids has been used to handle moderate power loads, reducing costs when compared to closed-circuit LN2 cryocoolers and mechanically decoupling flow-induced vibrations from the optics. To guarantee the functionality of such systems, lumped mass thermal models were implemented together with auxiliary finite elements analyses. With the first systems in operation, it has been possible to compare and validate the developed models, and to carry out optimizations to improve them for future projects, by adjusting parameters such as emissivity, thermal contact resistance, and copper braid conductance. This work presents the updated models for CARNAÚBA and CATERETÊ beamlines as reference cases.
 
poster icon Poster WEPC07 [18.496 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2020-WEPC07  
About • paper received ※ 12 August 2021       paper accepted ※ 28 September 2021       issue date ※ 07 November 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)