A stress analysis of the Sarafix external fixator design was performed using finite element analysis (FEA) and experimental tensometric measurements. The study was conducted at one of the Sarafix fixator configurati...A stress analysis of the Sarafix external fixator design was performed using finite element analysis (FEA) and experimental tensometric measurements. The study was conducted at one of the Sarafix fixator configurations that have a clinical application in the treatment of tibia fractures. The intensity of principal and yon Mises stresses generated at two measuring points (MP) on the fixator connecting rod were monitored and analyzed during the testing on axial compression on the fixator design and its finite element model (FEM). The 3D geometrical and FEM model of the fixator was formed using the computer aided design/computer aided engineering (CAD/CAE) software system CATIA. Verification of the results for the dominant principal stresses obtained from FEA was carried out through tensometric measurements. The measuring chain consisted of strain gauges connected into two Wheatstone half-bridges, digital measuring amplifier system and a computer with software for acquisition and monitoring of measurement results. A quite good agreement was observed between the results obtained on the basis of FEA and results of experimental tensometric analysis,展开更多
Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature di...Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature distributionand soot concentration of flames developed on the two-color principle. This system consists of an endoscope,an optical assembly with optical filters, a CCD camera, a frame grabber and associated image processingsoftware. Experiments are performed on a methane-air combustor and the temperature fields and the soot concentrationscorresponding to the flame images are obtained. The results have demonstrated that the system is capableof performing on-line measurement of flame and temperature distribution, providing temporal and spatial characterizationof the combustion process. In addition, the combination of advanced optical sensing and digital imageprocessing technique can help to define the threshold by the analysis of the background noise. Furthermore, theutilization of the filter technique can enhance the image presentation effect to an extent.展开更多
文摘A stress analysis of the Sarafix external fixator design was performed using finite element analysis (FEA) and experimental tensometric measurements. The study was conducted at one of the Sarafix fixator configurations that have a clinical application in the treatment of tibia fractures. The intensity of principal and yon Mises stresses generated at two measuring points (MP) on the fixator connecting rod were monitored and analyzed during the testing on axial compression on the fixator design and its finite element model (FEM). The 3D geometrical and FEM model of the fixator was formed using the computer aided design/computer aided engineering (CAD/CAE) software system CATIA. Verification of the results for the dominant principal stresses obtained from FEA was carried out through tensometric measurements. The measuring chain consisted of strain gauges connected into two Wheatstone half-bridges, digital measuring amplifier system and a computer with software for acquisition and monitoring of measurement results. A quite good agreement was observed between the results obtained on the basis of FEA and results of experimental tensometric analysis,
基金the National High Technology Research and Development of China (863 Program) (2006AA05A103)the National Natural Science Fund (grant No. 40501017, grant No. 50706053)
文摘Monitoring and control of combustion flames in utility boilers are required in order to optimize combustion conditions.This paper presents an instrumentation system for the concurrent measurement of the temperature distributionand soot concentration of flames developed on the two-color principle. This system consists of an endoscope,an optical assembly with optical filters, a CCD camera, a frame grabber and associated image processingsoftware. Experiments are performed on a methane-air combustor and the temperature fields and the soot concentrationscorresponding to the flame images are obtained. The results have demonstrated that the system is capableof performing on-line measurement of flame and temperature distribution, providing temporal and spatial characterizationof the combustion process. In addition, the combination of advanced optical sensing and digital imageprocessing technique can help to define the threshold by the analysis of the background noise. Furthermore, theutilization of the filter technique can enhance the image presentation effect to an extent.