Thermal Stability of the New ESRF Extremely Brilliant Source

Abstract

International audienceIn the frame of the Extremely Brilliant Source project (EBS), studies dedicated to disturbances have been more intensively investigated. Engineering instabilities have two origins: mechanical and thermal. Major thermal issues are: - air conditioning presents a temperature ramp up of 2°C along the sector - storage ring requires a warm up period of 4 days for reaching a stable orbit These effects have been observed and corrected for 20 years. With EBS requirements, we need to identify these thermal effects in order to reduce the disturbances, thus improving more systematically the source stability. The study is lead by the comparison between the present and the new thermal system. To do so, it is necessary to evaluate the heat balance in this system, as well as to identify the thermal time constant of each component. FEA models have been performed to reveal sensitivity of these thermal issues. A full scale mock-up cell equipped with a prototype girder is measured with power cables inside. A FEA model was also developed for the present storage ring to analyse the air stream. Although investigations have already been developed, some others remain to be achieved by the end of 2016