The conceptual design and thermal analysis of alba crotch absorbers

• Main Authors: Al-Dmour, E., Einfeld, D., Quispe, M.
• Format: Conference Proceeding
• Language: English
• Subjects: Capacitive sensors; Light sources; Magnetic analysis; Magnets; Storage rings; Stress; Structural beams; Synchrotrons; Temperature; Vacuum systems
• ISSN: 1944-4680; 2152-9582
• DOI: 10.1109/PAC.2007.4440191

ALBA is a 3 GeV, 268.8 m storage ring with extended Double Bend Achromat (DBA) structure under construction near Barcelona, Spain. With the design current of 400 mA, a total power of 407 kW is radiated by the circulating beam from the bending magnets. The design of the vacuum system was done by using the concept of the "crotch absorbers" which is used in many modern synchrotron light sources. These absorbers are not only going to absorb the power of the unused radiation but also will allow fast vacuum conditioning. 156 absorbers are need all around the machine in order to guarantee that no radiation will hit the chamber walls, the absorbers are grouped into three types, several design criteria have been studied in order to create our own one which is based on the number of allowed cycles before failure with the concept of the strain values. Finite element analysis (FEA) has been performed to estimate the stress, strain, maximum overall temperature and the maximum cooling temperature for all the types. The results for the critical absorber (type 3) under conservative conditions: max. overall temperature is 312.8degC, max. strain is 0.099 % and max. stress is 112.3 MPa. With this strain, the absorber can withstand up to 1.105 cycles of operation.