Research On The Hypoxic Experimental Cabin For Cultural Relics Research

The amount of Archaeology in China has increased rapidly in recent years.However,due to the lack of relative storage and study technology,it results in serious destruction of cultural relics after being unearthed.Besides,after the excavation of cultural relics,it is an advantage to grab the integrity of cultural relics information as soon as possible.The equipment that satisfies the suitable preservation and research environment use in unearthed site is necessary and urgently-needed.The shortcoming is that only a small nitrogen-filling protection device has developed recently,and,such devices can't achieve high effectiveness has been shown in the previous studies.The hypoxia experimental cabin used for cultural relics research in this context is completed under this background.Aiming at meeting the functional requirements of cultural relics preservation and research environment,the purpose of this paper is to build an experimental cabin use in unearthed site,parallel to the museum's cultural relic preservation environment level.The main control parameters in the experimental cabin including oxygen concentration,temperature and humidity,carbon dioxide concentration,illumination and pressure changes.The preservation and research environment established in the cabin is: rich nitrogen and low oxygen,adjustable cabin temperature,humidity and illumination conditions that satisfy different storage requirements.Meanwhile,the pressure change range and speed during the environment regulation in the cabin must be strictly controlled so as to avoid the influence of changes on the cultural relics and the researchers in the cabin.The concrete working process is as follows:Firstly,the design of each subsystem of the experimental cabin has been completed.The environmental control system has been established with SIEMENS 1215 PLC as the main control CPU.Secondly,the flow expression of the compressible fluid in the pipeline with the pressure ratio of the high and low pressure is derived based on the one-dimensional steady isentropic flow theory,and the actual flow characteristics of the vacuum pump and the regulating valve are obtained by combining the WINCC and the MATLAB platforms,then radicate the applicate scope of the theoretical formula and the empirical formula of the electric control valve,and the formula is corrected.In addition,the theoretical formula of the flow rate of the vacuum pump is corrected,and a mathematical model which is closer to the real situation of the system is set up.The two different ways of regulating oxygen concentration in cabin are analyzed,to find the optimized way.The experiment proves that the control processes that use PID in the cabin system hold good reactive and strong robustness.Besides,the LED lights are controlled by PWM to control the illumination of the cabin,and the methods control the temperature and humidity are designed in this paper.Experiments show that the processes that control correlative parameters satisfy the design error and achieve the requirements.Finally,this paper designs the control system and HMI system to complete the presence control process and administration.The remote control system and web browse function have been designed in this paper,which provide operators with sound and convenient system control,monitoring and data preservation methods,to expands the control and management interface of the system.