The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform
Zhai Tianbo - One of the best experts on this subject based on the ideXlab platform.
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Prediction of Coupling Guard Temperature and Gearbox Windage Power Loss
2017Co-Authors: Zhai TianboAbstract:Gear Windage Power Loss (WPL) is due to fluid drag experienced by a gear when it is rotating in air or an air-oil mist. Gear WPL becomes significant and shall not be neglected in high speed applications. The temperature on Coupling Guard needs to comply with industry standards and is influenced by windage affect. There is practical significance in predicting Coupling Guard temperature and gearbox WPL. Simulation models were built and results were obtained from Computational Fluid Dynamics (CFD) solvers. The simulation results were validated by experimental data from the literature. A case study was also conducted to further validate the predictability of Coupling Guard temperature. Simulation experiments were designed and data generated to obtain Multivariable Regression Formulas (MRF) for gear WPL and Guard temperature prediction. A comparison between CFD prediction of gear WPL and experimental results showed a relative error less than 12%. In the case study, the percentage difference between predicted Guard temperature and test data was within 5%. For the given ranges of input parameters, MRF gave a better prediction than the empirical formula used in industry. The proposed MRF was accurate for Coupling Guards and gears that were not included in the CFD modeled systems, which were used to generate the data for obtaining the MRF. The prediction expressions also helped in the product design stage to mitigate gearbox WPL and Coupling Guard temperature
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Coupling Guard Temperature And Windage Power Loss: Cfd Analysis And Experiments
Turbomachinery Laboratories Texas A&M Engineering Experiment Station, 2016Co-Authors: Thompson Adam, Zhai Tianbo, Palazzolo Alan, Keshmiri AmirAbstract:LectureHigh temperatures inside Coupling Guards can cause machinery down time and loss of revenue. As a result, many industries invest significant time and effort trying to reduce heat generation. Windage flanges are a standard feature on high performance Couplings with the purpose of reducing heat generation within Guards. However, previous testing and Computational Fluid Dynamic (CFD) simulation carried out by Pennington and Meck (2012) have cast doubt on the effectiveness of this feature. The forthcoming fifth edition of API 671 is expected to reduce the maximum allowable Guard temperature from 160°F (70°C) to 140°F (60°C), to reduce the risk of irreversible surface contact burns. In order to comply with the API requirement, it is important to understand how features such as windage flanges and radial Guard clearance affect heat generation. CFD analysis and physical testing are presented in this paper. Improvements to the test configuration setup have been made to achieve increased Coupling surface speeds of 175m/s (compared to 123m/s in previous testing by Pennington and Meck (2012)), and simplified to isolate the effects of the windage flange. This paper investigates the effectiveness of windage flanges, as well as the effect of Guard radial clearance on heat generation inside Coupling Guards, and resultant Coupling Guard temperature, at much higher speeds than in previous studies. In total, six test configurations were simulated, consisting of two test Couplings (with and without windage features) tested with three different sized Coupling Guards, creating variable radial clearances. CFD analysis results conclude that the windage flange features are ineffective in reducing heat generation inside the Guard, and Coupling Guards with a larger radial clearance result in lower temperatures inside the Guard. However, this approach is less effective above a Guard radial clearance of 40mm, after which the windage flange has little effect on the temperature within the Coupling Guard. In addition, temperature results from the validated CFD model were found to be within 4 percent of the physical experimental data
Keshmiri Amir - One of the best experts on this subject based on the ideXlab platform.
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Coupling Guard Temperature And Windage Power Loss: Cfd Analysis And Experiments
Turbomachinery Laboratories Texas A&M Engineering Experiment Station, 2016Co-Authors: Thompson Adam, Zhai Tianbo, Palazzolo Alan, Keshmiri AmirAbstract:LectureHigh temperatures inside Coupling Guards can cause machinery down time and loss of revenue. As a result, many industries invest significant time and effort trying to reduce heat generation. Windage flanges are a standard feature on high performance Couplings with the purpose of reducing heat generation within Guards. However, previous testing and Computational Fluid Dynamic (CFD) simulation carried out by Pennington and Meck (2012) have cast doubt on the effectiveness of this feature. The forthcoming fifth edition of API 671 is expected to reduce the maximum allowable Guard temperature from 160°F (70°C) to 140°F (60°C), to reduce the risk of irreversible surface contact burns. In order to comply with the API requirement, it is important to understand how features such as windage flanges and radial Guard clearance affect heat generation. CFD analysis and physical testing are presented in this paper. Improvements to the test configuration setup have been made to achieve increased Coupling surface speeds of 175m/s (compared to 123m/s in previous testing by Pennington and Meck (2012)), and simplified to isolate the effects of the windage flange. This paper investigates the effectiveness of windage flanges, as well as the effect of Guard radial clearance on heat generation inside Coupling Guards, and resultant Coupling Guard temperature, at much higher speeds than in previous studies. In total, six test configurations were simulated, consisting of two test Couplings (with and without windage features) tested with three different sized Coupling Guards, creating variable radial clearances. CFD analysis results conclude that the windage flange features are ineffective in reducing heat generation inside the Guard, and Coupling Guards with a larger radial clearance result in lower temperatures inside the Guard. However, this approach is less effective above a Guard radial clearance of 40mm, after which the windage flange has little effect on the temperature within the Coupling Guard. In addition, temperature results from the validated CFD model were found to be within 4 percent of the physical experimental data
Hardin James - One of the best experts on this subject based on the ideXlab platform.
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Computational Investigation of Coupling Guard Heating and Mitigation
Texas A&M University. Turbomachinery Laboratories, 2014Co-Authors: Jariwala Vishal, Turner Daryll, Hardin JamesAbstract:LectureHigh Coupling Guard temperature and oil misting on a power recovery expander led to a computational fluid dynamics (CFD) investigation of air flow and heat transfer in the Coupling Guard. The analyses included full 360-degree geometry, varying inlet and outlet configurations, different exhaust pressures, and both including and neglecting the flange bolt heads. With bolt heads included, the predicted Coupling Guard surface temperatures approximately matched values measured in the field. In the particular field problem addressed here, the measured temperatures were 219 to 222°F (104- 106°C), while the CFD predicted temperature ranged from 209- 227°F (98-108°C). Among the important findings are: The moving bolt heads generate much of the heat in a Coupling Guard; Properly placed outlet ports can use the bolt heads as a blower, increasing air flow through the Coupling Guard and lowering the temperature; Small reductions in exhaust pressure can lower the Coupling Guard surface temperature significantly. Numerous plots, graphs, and tables give insight into the flow field inside the Coupling Guard. These analyses can guide the design of Coupling Guards with lower surface temperatures
Thompson Adam - One of the best experts on this subject based on the ideXlab platform.
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Coupling Guard Temperature And Windage Power Loss: Cfd Analysis And Experiments
Turbomachinery Laboratories Texas A&M Engineering Experiment Station, 2016Co-Authors: Thompson Adam, Zhai Tianbo, Palazzolo Alan, Keshmiri AmirAbstract:LectureHigh temperatures inside Coupling Guards can cause machinery down time and loss of revenue. As a result, many industries invest significant time and effort trying to reduce heat generation. Windage flanges are a standard feature on high performance Couplings with the purpose of reducing heat generation within Guards. However, previous testing and Computational Fluid Dynamic (CFD) simulation carried out by Pennington and Meck (2012) have cast doubt on the effectiveness of this feature. The forthcoming fifth edition of API 671 is expected to reduce the maximum allowable Guard temperature from 160°F (70°C) to 140°F (60°C), to reduce the risk of irreversible surface contact burns. In order to comply with the API requirement, it is important to understand how features such as windage flanges and radial Guard clearance affect heat generation. CFD analysis and physical testing are presented in this paper. Improvements to the test configuration setup have been made to achieve increased Coupling surface speeds of 175m/s (compared to 123m/s in previous testing by Pennington and Meck (2012)), and simplified to isolate the effects of the windage flange. This paper investigates the effectiveness of windage flanges, as well as the effect of Guard radial clearance on heat generation inside Coupling Guards, and resultant Coupling Guard temperature, at much higher speeds than in previous studies. In total, six test configurations were simulated, consisting of two test Couplings (with and without windage features) tested with three different sized Coupling Guards, creating variable radial clearances. CFD analysis results conclude that the windage flange features are ineffective in reducing heat generation inside the Guard, and Coupling Guards with a larger radial clearance result in lower temperatures inside the Guard. However, this approach is less effective above a Guard radial clearance of 40mm, after which the windage flange has little effect on the temperature within the Coupling Guard. In addition, temperature results from the validated CFD model were found to be within 4 percent of the physical experimental data
Jariwala Vishal - One of the best experts on this subject based on the ideXlab platform.
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Computational Investigation of Coupling Guard Heating and Mitigation
Texas A&M University. Turbomachinery Laboratories, 2014Co-Authors: Jariwala Vishal, Turner Daryll, Hardin JamesAbstract:LectureHigh Coupling Guard temperature and oil misting on a power recovery expander led to a computational fluid dynamics (CFD) investigation of air flow and heat transfer in the Coupling Guard. The analyses included full 360-degree geometry, varying inlet and outlet configurations, different exhaust pressures, and both including and neglecting the flange bolt heads. With bolt heads included, the predicted Coupling Guard surface temperatures approximately matched values measured in the field. In the particular field problem addressed here, the measured temperatures were 219 to 222°F (104- 106°C), while the CFD predicted temperature ranged from 209- 227°F (98-108°C). Among the important findings are: The moving bolt heads generate much of the heat in a Coupling Guard; Properly placed outlet ports can use the bolt heads as a blower, increasing air flow through the Coupling Guard and lowering the temperature; Small reductions in exhaust pressure can lower the Coupling Guard surface temperature significantly. Numerous plots, graphs, and tables give insight into the flow field inside the Coupling Guard. These analyses can guide the design of Coupling Guards with lower surface temperatures
