The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air class...The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air classifier＇s structural design. The flow field characteristics of the rotor cage in turbo air classifiers were investigated trader different operating conditions by laser Doppler velocimeter（LDV）, and a measure diminishing the axial velocity is proposed. The investigation results show that the tangential velocity of the air flow inside the rotor cage is different from the rotary speed of the rotor cage on the same measurement point due to the influences of both the negative pressure at the exit and the rotation of the rotor cage. The tangential velocity of the air flow likewise decreases as the radius decreases in the case of the rotor cage＇s low rotary speed. In contrast, the tangential velocity of the air flow increases as the radius decreases in the case of the rotor cage＇s high rotary speed. Meanwhile, the vortex inside the rotor cage is found to occur near the pressure side of the blade when the rotor cage＇s rotary speed is less than the tangential velocity of air flow. On the contrary, the vortex is found to occur near the blade suction side once the rotor cage＇s rotary speed is higher than the tangential velocity of air flow. Inside the rotor cage, the axial velocity could not be disregarded and is largely determined by the distances between the measurement point and the exit.展开更多
The multi-fault phenomena are common in the turbo-rotor system of a liquidrocket engine. As it has many excellent qualities, the neural network might be used to solve theproblems of multi-fault diagnosis of a turbo-ro...The multi-fault phenomena are common in the turbo-rotor system of a liquidrocket engine. As it has many excellent qualities, the neural network might be used to solve theproblems of multi-fault diagnosis of a turbo-rotor system. First, the feature expression of a commonturbo-rotor fault was studied in order to build up the standard fault pattern and satisfy the needof neural network studying and diagnosing. Then, the turbo-rotor fault identification and diagnosisproblems were investigated by using a BP( back-propagation) neural network. According to the BPneural network problems, the parallel BP neural network method of multi-fault diagnosis andclassification was presented and investigated. The results indicated that the parallel BP neuralnetwork method could solve the turbo-rotor multi-fault diagnosis problems.展开更多
基金supported by National Natural Science Foundation of China (Grant No. 50474035)
文摘The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air classifier＇s structural design. The flow field characteristics of the rotor cage in turbo air classifiers were investigated trader different operating conditions by laser Doppler velocimeter（LDV）, and a measure diminishing the axial velocity is proposed. The investigation results show that the tangential velocity of the air flow inside the rotor cage is different from the rotary speed of the rotor cage on the same measurement point due to the influences of both the negative pressure at the exit and the rotation of the rotor cage. The tangential velocity of the air flow likewise decreases as the radius decreases in the case of the rotor cage＇s low rotary speed. In contrast, the tangential velocity of the air flow increases as the radius decreases in the case of the rotor cage＇s high rotary speed. Meanwhile, the vortex inside the rotor cage is found to occur near the pressure side of the blade when the rotor cage＇s rotary speed is less than the tangential velocity of air flow. On the contrary, the vortex is found to occur near the blade suction side once the rotor cage＇s rotary speed is higher than the tangential velocity of air flow. Inside the rotor cage, the axial velocity could not be disregarded and is largely determined by the distances between the measurement point and the exit.
文摘The multi-fault phenomena are common in the turbo-rotor system of a liquidrocket engine. As it has many excellent qualities, the neural network might be used to solve theproblems of multi-fault diagnosis of a turbo-rotor system. First, the feature expression of a commonturbo-rotor fault was studied in order to build up the standard fault pattern and satisfy the needof neural network studying and diagnosing. Then, the turbo-rotor fault identification and diagnosisproblems were investigated by using a BP( back-propagation) neural network. According to the BPneural network problems, the parallel BP neural network method of multi-fault diagnosis andclassification was presented and investigated. The results indicated that the parallel BP neuralnetwork method could solve the turbo-rotor multi-fault diagnosis problems.
