Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions
The operational rotational speeds of hydroturbines change arbitrarily within a small range, and the friction power consumption caused by the asymmetric curl represents a technical difficulty in magnetofluid sealing. In this study, the pressure-withstanding value and equations for the asymmetric curl...
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IEEE
2020-01-01
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| Series: | IEEE Access |
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| Online Access: | https://ieeexplore.ieee.org/document/9020178/ |
| _version_ | 1818735591108378624 |
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| author | Zhenggui Li Jie Cheng Deyou Li Xiaohui Deng Bing Dong Xiaobing Liu Biao Ma Xinrui Li |
| author_facet | Zhenggui Li Jie Cheng Deyou Li Xiaohui Deng Bing Dong Xiaobing Liu Biao Ma Xinrui Li |
| author_sort | Zhenggui Li |
| collection | DOAJ |
| description | The operational rotational speeds of hydroturbines change arbitrarily within a small range, and the friction power consumption caused by the asymmetric curl represents a technical difficulty in magnetofluid sealing. In this study, the pressure-withstanding value and equations for the asymmetric curl of a magnetofluid sealing device under different rotational speeds were deduced. By considering the magnetofluid sealing device characteristics with Halbach magnetic arrays, temperature fields under a static field and low rotational speed were calculated for determining the Halbach magnetofluid sealing device with the best sealing performance. Comparisons and analyses were performed with the friction power consumption and sealing pressure-withstanding value of the selected structure under high (3000 r/min), medium (1500 r/min), and low (300 r/min) rotational speeds and alternating work conditions of ±3, ±6, and ±9. The results indicated that changes in magnetic moment caused by changes in the external magnetic field are the primary cause of friction power consumption. Heat generation occurs concurrently with the friction power consumption. Consequently, the pressure-withstanding value of the magnetofluid sealing is reduced; the friction power consumption of the magnetofluid is directly proportional to the magnetic field strength, rotational speed, and alternating amplitude. Unstable states and asymmetry of the external magnetic field lead to nonlinear increments in the friction power consumption of the magnetofluid. A stable and symmetrical magnetic effect, with a smaller rotational speed and alternating amplitude leads to lower friction power consumption, resulting in a more ideal sealing effect. |
| first_indexed | 2024-12-18T00:23:41Z |
| format | Article |
| id | doaj.art-d522989734814936816340f667881f6c |
| institution | Directory Open Access Journal |
| issn | 2169-3536 |
| language | English |
| last_indexed | 2024-12-18T00:23:41Z |
| publishDate | 2020-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj.art-d522989734814936816340f667881f6c2022-12-21T21:27:17ZengIEEEIEEE Access2169-35362020-01-018494514946610.1109/ACCESS.2020.29776969020178Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work ConditionsZhenggui Li0Jie Cheng1https://orcid.org/0000-0002-3846-8392Deyou Li2Xiaohui Deng3Bing Dong4Xiaobing Liu5Biao Ma6Xinrui Li7Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaSchool of Energy Science and Engineering, Harbin Institute of Technology, Harbin, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaKey Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, ChinaThe operational rotational speeds of hydroturbines change arbitrarily within a small range, and the friction power consumption caused by the asymmetric curl represents a technical difficulty in magnetofluid sealing. In this study, the pressure-withstanding value and equations for the asymmetric curl of a magnetofluid sealing device under different rotational speeds were deduced. By considering the magnetofluid sealing device characteristics with Halbach magnetic arrays, temperature fields under a static field and low rotational speed were calculated for determining the Halbach magnetofluid sealing device with the best sealing performance. Comparisons and analyses were performed with the friction power consumption and sealing pressure-withstanding value of the selected structure under high (3000 r/min), medium (1500 r/min), and low (300 r/min) rotational speeds and alternating work conditions of ±3, ±6, and ±9. The results indicated that changes in magnetic moment caused by changes in the external magnetic field are the primary cause of friction power consumption. Heat generation occurs concurrently with the friction power consumption. Consequently, the pressure-withstanding value of the magnetofluid sealing is reduced; the friction power consumption of the magnetofluid is directly proportional to the magnetic field strength, rotational speed, and alternating amplitude. Unstable states and asymmetry of the external magnetic field lead to nonlinear increments in the friction power consumption of the magnetofluid. A stable and symmetrical magnetic effect, with a smaller rotational speed and alternating amplitude leads to lower friction power consumption, resulting in a more ideal sealing effect.https://ieeexplore.ieee.org/document/9020178/Hydroturbinemagnetofluid sealingHalbach magnetic arrayfriction power consumptionasymmetric curl |
| spellingShingle | Zhenggui Li Jie Cheng Deyou Li Xiaohui Deng Bing Dong Xiaobing Liu Biao Ma Xinrui Li Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions IEEE Access Hydroturbine magnetofluid sealing Halbach magnetic array friction power consumption asymmetric curl |
| title | Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions |
| title_full | Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions |
| title_fullStr | Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions |
| title_full_unstemmed | Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions |
| title_short | Characteristics of Asymmetric Curls of a Halbach Hydroturbine Main Shaft Magnetofluid Sealing Device Under Random Rotational Speed Work Conditions |
| title_sort | characteristics of asymmetric curls of a halbach hydroturbine main shaft magnetofluid sealing device under random rotational speed work conditions |
| topic | Hydroturbine magnetofluid sealing Halbach magnetic array friction power consumption asymmetric curl |
| url | https://ieeexplore.ieee.org/document/9020178/ |
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