Rheometer Used For Micro-Gravity Rheology Experiment

Research on rheology in micro-gravity is the cutting edge of the rheology filed,because traditional rheology experiment can never get rid of the layering effect of the sample by gravity.However,the space laboratory in the near orbit can provide the possibility of get rid of this interference.In 2015,NASA published its Shear History Extensional Rheology Experiment conducted in International Space Station,which obtained important data for science study.This article did a through introduce reference of the SHERE,as well as through study to the fundamental theory of commercial rheometers.A prototype rheometer was built based on the plan made on early study.Then a serial of experiments was conducted,some problems and improvements was discussed afterwards.At the engineering model designing chapter,the article discussed how the rheometer was designed suitable for launching,and simulated the structure with its 3D model.At last,the article did an early research on the key technologies of the torque sensor for rheology,and did a list of model simulation and experiments for verification.The main content is as follows:A thorough research and reference on public articles was made to study the NASA Shear History Extensional Rheology Experiment.For the reference of the rheometer in this article,the author gives a summarize of the science signification as well as its application perspective.And explained the principle and structure of SHERE equipment,the operation in Micro-Gravity Science Glovebox.The fundamental theory,mainly Newton Fluid Model,was explained for the developing of parallel plate rotary shearing theory.The author also worked out the error combination of this rotary type,which provided a foundation for prototype design.Then the article discussed the prototype developing,mainly about demand analysis and overall structure.A bunch of test was conducted and summarized the error source and other problems.The designing of the engineering model was on the base of the analysis of problems of prototype machine and on the demand of launch adaptation.The main work is on the structure vibration simulation.The result of harmonic response analysis and PSD analysis was discussed for the reference of designing.And also talked about the fast mechanical interface.A whole chapter was used to discuss the key points of torque sensor developing.The two key points are the elastomer designing of the torque sensor and the wireless power supply.The model of hollow axis was discussed and calculated,which can provide a certain parameter set for manufacture.An introduction on separated transformer leads to the torque sensor power supply parameter design.A set of test was made for verification.