| Fluid field in 20L HPBR is measured by Particle Image Velocimetry. And then the mathematical of momentum transfer in this HPBR is fitted, which is based on Computational Fluid Dynamics and the experiment data of PIV. This will provide base of the analysis, exploitation and scaling up design of the reactor in industry with the basic mathematic model.The typical fluid field in the stirred reactor is measured successfully by PIV technology, which will not only provide mature experiment measuring technique of fluid field for stirred reactor, but also provide the quantitative-full realization, analysis and simulation of momentum transfer process in HPBR with the basic experiment data. In the state of laminar flow(mix-rotate is 40r/min), the velocity and vorticity of unifoReity phase Newtonian fluid is minor, velocity of cross section and vertical section of impeller plane is (0.107633, 0.072766) m/s, vorticity of cross section and vertical section is (1.042773, 0.514864) rad/s. but its fluid field is well distributed, mixture of flow is plenary,its fluid state is typical: flow of cylindrical does unifoRe motion from top to bottom in the middle of reactor (R/Re=0～0.66), the flow of impeller area section does unifoRe motion along radial direction, flow of other sections does motion which is deviate radial direction or similar with circular motion; The flow doing axial decurrent motion meets the bottom of reactor and shoots all around at perimeter, then rebounds to upflow, which causes the velocity of decurrent flow in the cylindrical of R/Re=0.6～0.75 to reduce to 0, while the flow in the perimeter cirque of R/Re>0.75 whose motion is from bottom to top meets the flow in the middle whose motion is reverse direction, which foRes the process of sequence circulation flow in reactor. The upward flow of R/Re=0.9 has the highest velocity, the flow in the cylindrical of R/Re>0.9 enters the boundary quickly its radial velocity and radial velocity reduce to 0 rapidly. The degree of mixture is strengthened with speed of agitator's enhancing, compared to the velocity and the vorticity in the laminar flow state, the velocity in lower on flow state (mix-rotate is 180r/min) is enhanced. Velocity of cross section and vertical section of impeller plane in the laminar flow state is (0.169363, 0.151309) m/s, vorticity of cross section and vertical section is (1.77503, 1.803696) rad/s. We use the mature business software(CFX) of CFD not only to fit, prove the momentum and heat transfer model in HPBR with the experiment data of fluid field and temperature profile, but also to simulate the whole fluid field of H2O many types of fluids, such as H2O deviation values between the calculated values and experiment value are respectively 10.7% and 9.1% in the state of laminar flow, and 15.6and 14.8% in the state of onflow that are lower than the values(30%～40%) simulated by traditional empirical foReula, these will provide analysis of the transfer process in HPBR with reliable mechanism model and computing method. Under all of the operational conditions, there is the point at the boundary area of reactor wall and tubes, where the transfer resistance is high, whose deviation value is maximum. The result of analog calculation shows:①The classical Navier-Stokes equation is reliable mechanism equation which describes the momentum transfer of fluid in the state of laminar flow, the deviation values of fluid field for H2O system are minor than that of traditional empirical foReula when applying the equation effectively to simulate.② model which describes the momentum transfer process in lower onflow state predigests the actual and intricate onflow process.Based on operational principle of heat pipe, HPBR solves many problems on heat transfer in traditional bioreactor: nonunifoReity of temperature profile, inefficiency of heat transfer etc. The study in-depth on transfer process in HPBR will effectively accelerate exploitation for new-style bioreactor and advancement of biotechnology.
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