Research On Flow Field Dynamics And Measurement And Control Technology Of Animal Cell Suspension Culture

As people become increasingly concerned about the health care field, the demand for bio-pharmaceutical products increases gradually. Scale animal cell culture as the key technology for the preparation of biological products has become an important part of industrial production. Bioreactor is the core equipment to maintain the growth and reproduction of cells in vitro, in order to meet the requirement of high mixing uniformity and small shear stress in large scale animal cell culture, the research on the corresponding reactor is one of the most difficult problems. The computational fluid dynamics software can comprehensive simulate the bioreactor flow state, and the calculation results of key engineering factors directly reflect the characteristics of the flow field, so as to provide the basis for the design of reactor parameters and structure. Meanwhile, the industrial cultivation of the animal cell culture scale also brings challenges for the measurement and control of process parameters, the accurate measurement of key parameters is a necessary prerequisite to control, but due to the limitation of traditional measurement technique and the complexity of animal cell culture process, the measurement of key parameters has been the primary problem in the process of measurement and control. These technical issues are closely related to the yield and quality of the final product of animal cell culture, so it is necessary to deeply study these technical problems, which has practical value and significance.In view of the above technical problems, this paper expanded research mainly from the following several aspects:1. Fluid simulation software CFX was used in the reactor flow field simulation,the 4000 L animal cell bioreactor was used as the research object. Firstly the geometric structure of the flow field computational domain and the agitator structure were designed. Then in the finite element analysis software, the multiple reference coordinate method was used to partition the computational domain, the flow field effect of different baffle groups in the reactor was simulated by fluid simulationsoftware CFX, and the choice of the optimal baffle number was determined according to the simulation results. Finally the flow field of different stirring speed was calculated,the comparative analysis of the simulation results of the velocity vector field and shear vector field provided a basis for the stirring speed setting in the practical production process.2. The soft sensing technology was used to solve the prediction problem of the key unpredictable parameters in the animal cell culture. The foot-and-mouth disease vaccine suspension culture is taken as the research object, the uniform incidence degree algorithm is used to select the auxiliary variables, and the soft sensing model based on generalized regression neural network was established to predict the key parameters of glucose concentration, lactic acid concentration, alanine concentration and cell density. Compared with prediction effects of radial basis function neural network model in the simulation experiment, the simulation results showed that the generalized regression neural network possessed the more excellent prediction accuracy and generalization ability, also indicated that it has feasibility in the soft sensing modeling for the animal cell culture process.3. The digital control system of animal cell culture provides the platform for the monitoring and control of animal cell culture research which is applied to the actual production. This paper used the ARM9 microprocessor as the main control CPU to design the digital control system for animal cell culture. First of all, the hardware control system was designed based on ARM9, and the data storage and communication interface technology in digital system were described in detail, then the actual detection methods of temperature, dissolved oxygen, pH and the communication interface technology were designed, at last the software operating system Lniux was transplanted into the controller to build a complete set of digital control system for animal cell culture.