Research And Implementation Of The Integrated Cooling System For Porous Array Focal Plate

With the rapid development of multi-objective astronomical survey telescope technology,the heat of focal plate which high-density optical fiber positioners were mounted in has become the key factor of system precision.The high-density heat distribution will lead to the temperature rise of focal plate,the temperature deformation of focal plate,and bad telescope atmospheric seeing,thereby the telescope observation will be affected.The new integrated cooling design was proposed to solve the above problems,the multi curve composite grooves located in the gap on the focal plate surface with hole array were designed for forced convection,meanwhile,the active temperature control focal plate was achieved by the precise temperature control of the cooling medium.The multi curved composite grooves should not only to meet the requirements of heat dissipation and space of high-density optical fiber positioners,but also to solve the problem of manufacturing and sealing in the narrow space of the focal plate,and to maintain mechanical properties of the whole system at the same time.The focal plate was modeled by CAD software and its stiffness was analyzed by finite element software.The velocity distribution of the cooling medium was studied by the fluid simulation software,and the simulation of focal plate temperature field was carried out in different inlet water temperature.The model of the focal plate was fabricated and the experimental platform of cooling system was built.The pressure and sealing of the focal plate are tested,then the experiment was carried out to analyze the cooling effect of the integrated cooling system for focal plate.At last,the active temperature control module for focal plate was designed,the precise temperature control of the cooling medium was achieved,and the effect of the active temperature control on the ambient temperature of focal plate was analyzed by the simulation.The simulation and experimental results suggested that the integrated cooling system designed in this paper can ensure the temperature field of focal plate stabled and the uniform distribution of focal plate temperature,meanwhile,the temperature change of whole focal plate can be controlled in a constant range during the course of working of fiber positioning units.The design of the active temperature control for the integrated cooling system for focal plate can achieve that the temperature of the cooling medium change with the ambient temperature of focal plate,thereby that will not make an effect on the ambient temperature of focal plate.