The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Y Shi - One of the best experts on this subject based on the ideXlab platform.
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Multidisciplinary analysis transient flow effects on the Impeller in a semi-Open centrifugal Impeller stage
2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-Open Impeller stage of a centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-Open Impeller stage of a centrifugal compressor.
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Study on unsteady flow collaborative characteristics of semi-Open Impeller and diffuser in a centrifugal compressor
Proceedings of the 2014 IEEE 18th International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2014Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressor, as the significant equipment in the energy field, is of very complexity in its structure. Good collaboration of individual components determines the good aerodynamic performance and running security of the compressor. Unsteady simulations were performed, based on the platform of CFX and through the UDF interface program, to evaluate the 3D collaborative aerodynamic characteristics of a semi-Open Impeller and diffuser in a large centrifugal compressor, and the numerical study was focused on the Impeller-diffuser interaction. The result obtained from flow structures shows the development of low-velocity vortexes in the diffuser flow passage is affected by Impeller-diffuser interaction. The low-velocity vortex may increase flow resistance of the flow passage, however, improving at some extent the flow condition of the neighbor one, which generates a kind of low-frequency interference. In addition, the strongest interface effect is located on the rotor blade trailing edge and the diffuser vane leading edge. Amplitude-frequency characteristics converted from the pressure pulsation on monitor points indicate that the rotor wake flow and potential repercussion of diffuser work together to generate strong vibration and excitation force. The Impeller-diffuser interaction is stronger under winter operating condition than it is under design condition. Meanwhile, the impact of diffuser exerts dominating effects on the excitation force near the Impeller, which should be considered when exploring the Impeller damage accident causes under winter operating condition.
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Study on methods of numerical simulation of transient flow in the semi-Open Impeller stage of a centrifugal compressor
Energy Education Science and Technology Part A: Energy Science and Research, 2014Co-Authors: Rong Xie, Wang Miao, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors are vital energy conversion equipment and widely used in Petrochemical industries. The flow complex and unsteady features in compressor stage have an impact on the safety of compressor operating. The transient flow characteristics were numerically simulated in the semi-Open Impeller stage of one large compressor. By using the phase lagged method and the domain scaling method, two different interface approaches, and solving the three dimensional density-based Reynoldsaveraged N-S equation, the static pressure fluctuation on the Impeller blades surface was obtained. The flow in the Impeller was analyzed according to the dynamic load characteristics of the Impeller blades surface, and then the difference between the domain scaling method and the phase lagged method was discussed and summarized. Theoretical studies show that the dynamic load is the incentive of fatigue failure of compressor Impellers. The numerical results indicate that the dynamic load on the studied Impeller blades surface is much lower than that inducing fatigue failure. The conclusions of this study provide the numerical basis for the choice of suitable method for numerical simulation of transient flow in the centrifugal compressor stage, and as well as the guidance for the reason investigation of Impeller blades fracture under off-operating conditions. © Sila Science.
L. Guan - One of the best experts on this subject based on the ideXlab platform.
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Multidisciplinary analysis transient flow effects on the Impeller in a semi-Open centrifugal Impeller stage
2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-Open Impeller stage of a centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-Open Impeller stage of a centrifugal compressor.
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CSCWD - Multidisciplinary analysis transient flow effects on the Impeller in a semi-Open centrifugal Impeller stage
2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017Co-Authors: L. GuanAbstract:Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-Open Impeller stage of a centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-Open Impeller stage of a centrifugal compressor.
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a simplified model of semi Open Impeller stage and analysis of its effects on the transient flow
Applied Mechanics and Materials, 2014Co-Authors: L. Guan, Zi Fu LuAbstract:The centrifugal compressor is one type of vital energy conversion equipment and its unsteady characteristics are extremely complex in actual operation. A semi-Open Impeller stage with inlet guide vanes, an Impeller and a diffuser in a centrifugal compressor was concerned. For simulation of unsteady flow, the full-passage model of the integrate stage requires much more simulating time and memory space, higher computer configuration. Therefore, a single-passage simplified model was established for unsteady analysis. The internal flow characteristics and aerodynamic load on the blade obtained by the simplified model were also compared with that by the full-passage model. The result shows that the precision of the simplified model can meet the engineering requirement. Compared with the full-passage model, the simplified model can give a relatively true reflection of the local flow characteristics and the aerodynamic load on blade surfaces, but it ignores the unevenness resulted from unsteadiness along circumferential direction. Only high-frequency information is retained in aerodynamic load analysis while low-frequency one is diluted. However, as far as the local flow pattern or high-frequency information resulted from unsteady effects is concerned, the simplified model provides the advantages of higher computational efficiency and lower hardware requirements.
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Study on unsteady flow collaborative characteristics of semi-Open Impeller and diffuser in a centrifugal compressor
Proceedings of the 2014 IEEE 18th International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2014Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressor, as the significant equipment in the energy field, is of very complexity in its structure. Good collaboration of individual components determines the good aerodynamic performance and running security of the compressor. Unsteady simulations were performed, based on the platform of CFX and through the UDF interface program, to evaluate the 3D collaborative aerodynamic characteristics of a semi-Open Impeller and diffuser in a large centrifugal compressor, and the numerical study was focused on the Impeller-diffuser interaction. The result obtained from flow structures shows the development of low-velocity vortexes in the diffuser flow passage is affected by Impeller-diffuser interaction. The low-velocity vortex may increase flow resistance of the flow passage, however, improving at some extent the flow condition of the neighbor one, which generates a kind of low-frequency interference. In addition, the strongest interface effect is located on the rotor blade trailing edge and the diffuser vane leading edge. Amplitude-frequency characteristics converted from the pressure pulsation on monitor points indicate that the rotor wake flow and potential repercussion of diffuser work together to generate strong vibration and excitation force. The Impeller-diffuser interaction is stronger under winter operating condition than it is under design condition. Meanwhile, the impact of diffuser exerts dominating effects on the excitation force near the Impeller, which should be considered when exploring the Impeller damage accident causes under winter operating condition.
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CSCWD - Study on unsteady flow collaborative characteristics of semi-Open Impeller and diffuser in a centrifugal compressor
Proceedings of the 2014 IEEE 18th International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2014Co-Authors: L. GuanAbstract:Centrifugal compressor, as the significant equipment in the energy field, is of very complexity in its structure. Good collaboration of individual components determines the good aerodynamic performance and running security of the compressor. Unsteady simulations were performed, based on the platform of CFX and through the UDF interface program, to evaluate the 3D collaborative aerodynamic characteristics of a semi-Open Impeller and diffuser in a large centrifugal compressor, and the numerical study was focused on the Impeller-diffuser interaction. The result obtained from flow structures shows the development of low-velocity vortexes in the diffuser flow passage is affected by Impeller-diffuser interaction. The low-velocity vortex may increase flow resistance of the flow passage, however, improving at some extent the flow condition of the neighbor one, which generates a kind of low-frequency interference. In addition, the strongest interface effect is located on the rotor blade trailing edge and the diffuser vane leading edge. Amplitude-frequency characteristics converted from the pressure pulsation on monitor points indicate that the rotor wake flow and potential repercussion of diffuser work together to generate strong vibration and excitation force. The Impeller-diffuser interaction is stronger under winter operating condition than it is under design condition. Meanwhile, the impact of diffuser exerts dominating effects on the excitation force near the Impeller, which should be considered when exploring the Impeller damage accident causes under winter operating condition.
Takashi Yamane - One of the best experts on this subject based on the ideXlab platform.
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Geometric Optimization of a Step Bearing for a Hydrodynamically Levitated Centrifugal Blood Pump for the Reduction of Hemolysis
Artificial Organs, 2013Co-Authors: Ryo Kosaka, Masahiro Nishida, Osamu Maruyama, Toru Yada, Takashi YamaneAbstract:A hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller has been developed for mechanical circulatory assistance. However, a narrow bearing gap has the potential to cause hemolysis. The purpose of the present study is to optimize the geometric configuration of the hydrodynamic step bearing in order to reduce hemolysis by expansion of the bearing gap. First, a numerical analysis of the step bearing, based on lubrication theory, was performed to determine the optimal design. Second, in order to assess the accuracy of the numerical analysis, the hydrodynamic forces calculated in the numerical analysis were compared with those obtained in an actual measurement test using Impellers having step lengths of 0%, 33%, and 67% of the vane length. Finally, a bearing gap measurement test and a hemolysis test were performed. As a result, the numerical analysis revealed that the hydrodynamic force was the largest when the step length was approximately 70%. The hydrodynamic force calculated in the numerical analysis was approximately equivalent to that obtained in the measurement test. In the measurement test and the hemolysis test, the blood pump having a step length of 67% achieved the maximum bearing gap and reduced hemolysis, as compared with the pumps having step lengths of 0% and 33%. It was confirmed that the numerical analysis of the step bearing was effective, and the developed blood pump having a step length of approximately 70% was found to be a suitable configuration for the reduction of hemolysis.
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Effect of a bearing gap on hemolytic property in a hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller.
Bio-medical Materials and Engineering, 2013Co-Authors: Ryo Kosaka, Masahiro Nishida, Osamu Maruyama, Tomoyuki Yambe, Kou Imachi, Takashi YamaneAbstract:We have developed a hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller for long-term circulatory assist. The pump uses hydrodynamic bearings to enhance durability and reliability without additional displacement- sensors or control circuits. However, a narrow bearing gap of the pump has a potential for hemolysis. The purpose of this study is to develop the hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller, and to evaluate the effect of a bearing gap on hemolytic property. The Impeller levitates using a spiral-groove type thrust bearing, and a herringbone-groove type radial bearing. The pump design was improved by adopting a step type thrust bearing and optimizing the pull-up magnetic force. The pump performance was evaluated by a levitation performance test, a hemolysis test and an animal experiment. In these tests, the bearing gap increased from 1 to 63 µm. In addition, the normalized index of hemolysis (NIH) improved from 0.415 to 0.005 g/100 l, corresponding to the expansion of the bearing gap. In the animal experiment for 24 h, the plasma-free hemoglobin remained within normal ranges (
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effect of a bearing gap on hemolytic property in a hydrodynamically levitated centrifugal blood pump with a semi Open Impeller
Bio-medical Materials and Engineering, 2013Co-Authors: Ryo Kosaka, Masahiro Nishida, Osamu Maruyama, Tomoyuki Yambe, Kou Imachi, Takashi YamaneAbstract:We have developed a hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller for long-term circulatory assist. The pump uses hydrodynamic bearings to enhance durability and reliability without additional displacement- sensors or control circuits. However, a narrow bearing gap of the pump has a potential for hemolysis. The purpose of this study is to develop the hydrodynamically levitated centrifugal blood pump with a semi-Open Impeller, and to evaluate the effect of a bearing gap on hemolytic property. The Impeller levitates using a spiral-groove type thrust bearing, and a herringbone-groove type radial bearing. The pump design was improved by adopting a step type thrust bearing and optimizing the pull-up magnetic force. The pump performance was evaluated by a levitation performance test, a hemolysis test and an animal experiment. In these tests, the bearing gap increased from 1 to 63 µm. In addition, the normalized index of hemolysis (NIH) improved from 0.415 to 0.005 g/100 l, corresponding to the expansion of the bearing gap. In the animal experiment for 24 h, the plasma-free hemoglobin remained within normal ranges (<4.0 mg/dl). We confirmed that the hemolytic property of the pump was improved to the acceptable level by expanding the bearing gap greater than 60 µm.
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EMBC - Improvement of hemocompatibility for hydrodynamic levitation centrifugal pump by optimizing step bearings
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011Co-Authors: Ryo Kosaka, Masahiro Nishida, Osamu Maruyama, Toru Yada, Takashi YamaneAbstract:We have developed a hydrodynamic levitation centrifugal blood pump with a semi-Open Impeller for a mechanically circulatory assist. The Impeller levitated with original hydrodynamic bearings without any complicated control and sensors. However, narrow bearing gap has the potential for causing hemolysis. The purpose of the study is to investigate the geometric configuration of the hydrodynamic step bearing to minimize hemolysis by expansion of the bearing gap. Firstly, we performed the numerical analysis of the step bearing based on Reynolds equation, and measured the actual hydrodynamic force of the step bearing. Secondly, the bearing gap measurement test and the hemolysis test were performed to the blood pumps, whose step length were 0 %, 33 % and 67 % of the vane length respectively. As a result, in the numerical analysis, the hydrodynamic force was the largest, when the step bearing was around 70 %. In the actual evaluation tests, the blood pump having step 67 % obtained the maximum bearing gap, and was able to improve the hemolysis, compared to those having step 0% and 33%. We confirmed that the numerical analysis of the step bearing worked effectively, and the blood pump having step 67 % was suitable configuration to minimize hemolysis, because it realized the largest bearing gap.
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improvement of hemocompatibility in centrifugal blood pump with hydrodynamic bearings and semi Open Impeller in vitro evaluation
Artificial Organs, 2009Co-Authors: Ryo Kosaka, Masahiro Nishida, Osamu Maruyama, Toru Yada, Sakae Saito, Shusaku Hirai, Takashi YamaneAbstract:We have developed a noncontact-type centrifugal blood pump with hydrodynamic bearings and a semi-Open Impeller for mechanical circulatory assist. The Impeller is levitated by an original spiral-groove thrust bearing and a herringbone-groove journal bearing, without any additional displacement-sensing module or additional complex control circuits. The pump was improved by optimizing the groove direction of the spiral-groove thrust bearing and the pull-up magnetic force between the rotor magnet and the stator coil against the Impeller. To evaluate hemocompatibility, we conducted a levitation performance test and in vitro hemocompatibility tests by means of a mock-up circulation loop. In the hemolysis test, the normalized index of hemolysis was reduced from 0.721 to 0.0335 g/100 L corresponding to an expansion of the bearing gap from 1.1 to 56.1 µm. In the in vitro antithrombogenic test, blood pumps with a wide thrust bearing gap were effective in preventing thrombus formation. Through in vitro evaluation tests, we confirmed that hemocompatibility was improved by balancing the hydrodynamic fluid dynamics and magnetic forces.
Rong Xie - One of the best experts on this subject based on the ideXlab platform.
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Multidisciplinary analysis transient flow effects on the Impeller in a semi-Open centrifugal Impeller stage
2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-Open Impeller stage of a centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-Open Impeller stage of a centrifugal compressor.
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Study on unsteady flow collaborative characteristics of semi-Open Impeller and diffuser in a centrifugal compressor
Proceedings of the 2014 IEEE 18th International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2014Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressor, as the significant equipment in the energy field, is of very complexity in its structure. Good collaboration of individual components determines the good aerodynamic performance and running security of the compressor. Unsteady simulations were performed, based on the platform of CFX and through the UDF interface program, to evaluate the 3D collaborative aerodynamic characteristics of a semi-Open Impeller and diffuser in a large centrifugal compressor, and the numerical study was focused on the Impeller-diffuser interaction. The result obtained from flow structures shows the development of low-velocity vortexes in the diffuser flow passage is affected by Impeller-diffuser interaction. The low-velocity vortex may increase flow resistance of the flow passage, however, improving at some extent the flow condition of the neighbor one, which generates a kind of low-frequency interference. In addition, the strongest interface effect is located on the rotor blade trailing edge and the diffuser vane leading edge. Amplitude-frequency characteristics converted from the pressure pulsation on monitor points indicate that the rotor wake flow and potential repercussion of diffuser work together to generate strong vibration and excitation force. The Impeller-diffuser interaction is stronger under winter operating condition than it is under design condition. Meanwhile, the impact of diffuser exerts dominating effects on the excitation force near the Impeller, which should be considered when exploring the Impeller damage accident causes under winter operating condition.
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Study on methods of numerical simulation of transient flow in the semi-Open Impeller stage of a centrifugal compressor
Energy Education Science and Technology Part A: Energy Science and Research, 2014Co-Authors: Rong Xie, Wang Miao, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors are vital energy conversion equipment and widely used in Petrochemical industries. The flow complex and unsteady features in compressor stage have an impact on the safety of compressor operating. The transient flow characteristics were numerically simulated in the semi-Open Impeller stage of one large compressor. By using the phase lagged method and the domain scaling method, two different interface approaches, and solving the three dimensional density-based Reynoldsaveraged N-S equation, the static pressure fluctuation on the Impeller blades surface was obtained. The flow in the Impeller was analyzed according to the dynamic load characteristics of the Impeller blades surface, and then the difference between the domain scaling method and the phase lagged method was discussed and summarized. Theoretical studies show that the dynamic load is the incentive of fatigue failure of compressor Impellers. The numerical results indicate that the dynamic load on the studied Impeller blades surface is much lower than that inducing fatigue failure. The conclusions of this study provide the numerical basis for the choice of suitable method for numerical simulation of transient flow in the centrifugal compressor stage, and as well as the guidance for the reason investigation of Impeller blades fracture under off-operating conditions. © Sila Science.
M. Hao - One of the best experts on this subject based on the ideXlab platform.
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Multidisciplinary analysis transient flow effects on the Impeller in a semi-Open centrifugal Impeller stage
2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-Open Impeller stage of a centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-Open Impeller stage of a centrifugal compressor.
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Study on unsteady flow collaborative characteristics of semi-Open Impeller and diffuser in a centrifugal compressor
Proceedings of the 2014 IEEE 18th International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2014Co-Authors: Rong Xie, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressor, as the significant equipment in the energy field, is of very complexity in its structure. Good collaboration of individual components determines the good aerodynamic performance and running security of the compressor. Unsteady simulations were performed, based on the platform of CFX and through the UDF interface program, to evaluate the 3D collaborative aerodynamic characteristics of a semi-Open Impeller and diffuser in a large centrifugal compressor, and the numerical study was focused on the Impeller-diffuser interaction. The result obtained from flow structures shows the development of low-velocity vortexes in the diffuser flow passage is affected by Impeller-diffuser interaction. The low-velocity vortex may increase flow resistance of the flow passage, however, improving at some extent the flow condition of the neighbor one, which generates a kind of low-frequency interference. In addition, the strongest interface effect is located on the rotor blade trailing edge and the diffuser vane leading edge. Amplitude-frequency characteristics converted from the pressure pulsation on monitor points indicate that the rotor wake flow and potential repercussion of diffuser work together to generate strong vibration and excitation force. The Impeller-diffuser interaction is stronger under winter operating condition than it is under design condition. Meanwhile, the impact of diffuser exerts dominating effects on the excitation force near the Impeller, which should be considered when exploring the Impeller damage accident causes under winter operating condition.
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Study on methods of numerical simulation of transient flow in the semi-Open Impeller stage of a centrifugal compressor
Energy Education Science and Technology Part A: Energy Science and Research, 2014Co-Authors: Rong Xie, Wang Miao, M. Hao, L. Guan, Y ShiAbstract:Centrifugal compressors are vital energy conversion equipment and widely used in Petrochemical industries. The flow complex and unsteady features in compressor stage have an impact on the safety of compressor operating. The transient flow characteristics were numerically simulated in the semi-Open Impeller stage of one large compressor. By using the phase lagged method and the domain scaling method, two different interface approaches, and solving the three dimensional density-based Reynoldsaveraged N-S equation, the static pressure fluctuation on the Impeller blades surface was obtained. The flow in the Impeller was analyzed according to the dynamic load characteristics of the Impeller blades surface, and then the difference between the domain scaling method and the phase lagged method was discussed and summarized. Theoretical studies show that the dynamic load is the incentive of fatigue failure of compressor Impellers. The numerical results indicate that the dynamic load on the studied Impeller blades surface is much lower than that inducing fatigue failure. The conclusions of this study provide the numerical basis for the choice of suitable method for numerical simulation of transient flow in the centrifugal compressor stage, and as well as the guidance for the reason investigation of Impeller blades fracture under off-operating conditions. © Sila Science.
