The ventilators have been vividly called ＂the lungs of mine＂. The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timi...The ventilators have been vividly called ＂the lungs of mine＂. The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timing method based on the fiber Bragg grating magnetically coupling sensor to study and analyze the ventilator blade vibration, in order to realize long-distance and non-contact real-time online safety monitoring of blade vibration. Compared with the electronic sensorand fiber intensity reflective sensor, the fiber grating coupling magnetic sensor has such advantages as explosion-proof, working at harsh environment with humid air, dust and greasy dirt, capable of achieving long-distance signal transmission, and joining easily with other fiber Bragg grating sensors to form a network in order to achieve multi-parameter distributed online monitoring.展开更多
The vortex-induced vibrations(VIV)is an important topic of study in many different scientific and engineering fields.While VIV can be of benefit in some cases,oftentimes,it is an undesirable phenomenon that can be qui...The vortex-induced vibrations(VIV)is an important topic of study in many different scientific and engineering fields.While VIV can be of benefit in some cases,oftentimes,it is an undesirable phenomenon that can be quite dangerous.In particular for offshore pipelines,VIV can lead to fatiguing of the pipe structure and can cause disastrous consequences if left unchecked.A number of different methods have been applied to the measurement of VIV,especially for the elongated,thin cylindrical structures.The use of fiber optic fiber Bragg gratings(FBGs)in particular has gained popularity over the recent years due to their distinct properties.However,FBGs are also very fragile and are susceptible to failure when placed in harsh environments without protection.In this paper,56 FBGs encapsulated in stainless steel tubes were applied to the measurement of VIV in a28-m model pipeline under controlled and uncontrolled conditions.Tests show that the encapsulated sensors possessed good sensitivity as well as fatigue life(>80000 cycles).The measurements from FBGs were also high enough to allow frequency domain analysis of the pipeline VIV under the two conditions.The authors conclude that the encapsulated FBGs are a viable tool for the study of VIV in pipeline structures.展开更多
文摘The ventilators have been vividly called ＂the lungs of mine＂. The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timing method based on the fiber Bragg grating magnetically coupling sensor to study and analyze the ventilator blade vibration, in order to realize long-distance and non-contact real-time online safety monitoring of blade vibration. Compared with the electronic sensorand fiber intensity reflective sensor, the fiber grating coupling magnetic sensor has such advantages as explosion-proof, working at harsh environment with humid air, dust and greasy dirt, capable of achieving long-distance signal transmission, and joining easily with other fiber Bragg grating sensors to form a network in order to achieve multi-parameter distributed online monitoring.
基金supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grand No.51121005)the National Natural Science Foundation of China(Grand No.51108059)+2 种基金the Special Fund for Basic Research on Scientific Instruments of the National Natural Science Foundation of China(Grand No.51327003)the Special Project of China Earthquake Administration(Grand No.2015419014)China Scholarship Council(Grand No.201206060081)
文摘The vortex-induced vibrations(VIV)is an important topic of study in many different scientific and engineering fields.While VIV can be of benefit in some cases,oftentimes,it is an undesirable phenomenon that can be quite dangerous.In particular for offshore pipelines,VIV can lead to fatiguing of the pipe structure and can cause disastrous consequences if left unchecked.A number of different methods have been applied to the measurement of VIV,especially for the elongated,thin cylindrical structures.The use of fiber optic fiber Bragg gratings(FBGs)in particular has gained popularity over the recent years due to their distinct properties.However,FBGs are also very fragile and are susceptible to failure when placed in harsh environments without protection.In this paper,56 FBGs encapsulated in stainless steel tubes were applied to the measurement of VIV in a28-m model pipeline under controlled and uncontrolled conditions.Tests show that the encapsulated sensors possessed good sensitivity as well as fatigue life(>80000 cycles).The measurements from FBGs were also high enough to allow frequency domain analysis of the pipeline VIV under the two conditions.The authors conclude that the encapsulated FBGs are a viable tool for the study of VIV in pipeline structures.
