Temperature Rise and Thermal Deformation of Magnetic Pole of MLDSB under Multiple Physical Field Coupling

Abstract The thermal deformation of magnetic poles caused by the heat loss of the coils of Magnetic Liquid Double Suspension Bearing (MLDSB) can reduced the gap between magnetic poles and magnetic sleeve, and the probability and degree of impact-rub can be increased in the working process of MLDSB. And the coatings of magnetic poles and magnetic sleeve can be worn overly, and the operation stability and service life of MLDSB will be reduced severely. The thermal deformation of magnetic poles can be affected by the material property of magnetic pole, the electric current of the coils, and the cooling effect of the lubricants and so on, so it belongs to the multiple physical field coupling. Therefore, the flow-solid-thermal coupled mathematics model of MLDSB is established and solved with ANSYS in this paper, and the distribution law of flow field of the magnetic pole is explored. The transfer path and distribution principles of heat loss are revealed and the distribution law of temperature rise and thermal deformation of magnetic pole in different operating conditions are explored. The results indicate that the temperature rise and thermal deformation of the stator is symmetrically distributed in the center, it gradually increase from the outside to the center, and the thermal deformation near the corner of magnetic pole is largest. The most heat loss can be taken away by the lubricants under the condition of heat balance. The thermal deformation of magnetic pole can increase linearly as the current gradually increase, and the stress is concentrated in the threaded hole and magnetic pole. The thermal deformation decreases linearly as the inlet pressure of the lubricants gradually increase. The PIV results of flow trace are basically consistent with the simulation results. The research in this paper can provide the theoretical reference for the structural design and the optimization of MLDSB.

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Defects detection of Vehicle Steering Knuckle Based on Magnetic-acoustic Multi-physical Field Coupling Technology

2019 IEEE 28th International Symposium on Industrial Electronics (ISIE) ◽

10.1109/isie.2019.8781474 ◽

2019 ◽

Author(s):

Xin Huang ◽

Xuyun Qiu ◽

Aijuan Li ◽

Yumin Song

Keyword(s):

Physical Field ◽

Field Coupling

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Numerical Evaluation and Experimental Test on a New Giant Magnetostrictive Transducer with Low Heat Loss Design

Micromachines ◽

10.3390/mi12111397 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1397

Author(s):

Zhuan Bai ◽

Zonghe Zhang ◽

Ju Wang ◽

Xiaoqing Sun ◽

Wei Hu

Keyword(s):

Heat Loss ◽

Temperature Rise ◽

Magnetic Energy ◽

Mechanical Energy ◽

Electric Energy ◽

Energy Utilization ◽

Element Analysis ◽

Excessive Heat ◽

Excitation Coil ◽

Magnetostrictive Transducer

Giant magnetostrictive transducer with micro and nano precision has a wide application prospect in the field of remote sensing. However, excessive heat loss of components could generate during the energy conversion and transfer from electric energy to magnetic energy, and magnetic energy to mechanical energy, thereby affecting its long-term service and also reducing energy utilization. In this paper, a new magnetostrictive transducer is proposed and its excitation coil, internal and external magnetic circuit are optimized from the perspective of reducing heat loss. With the help of theoretical and finite element analysis, the response law between key parameters and heat loss of key components are summarized, which provides a basis for reducing heat loss. Finally, according to the optimization scheme, the prototype is processed, and the temperature rise and dynamic output performance of the transducer are tested by constructing an experimental setup. The results show that the transducer has a low temperature rise and good frequency response characteristics, which can provide support for long-time precise actuation on-orbit.

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HIDDEN DIRAC MONOPOLES

International Journal of Modern Physics A ◽

10.1142/s0217751x08041669 ◽

2008 ◽

Vol 23 (24) ◽

pp. 4023-4037 ◽

Cited By ~ 7

Author(s):

VICENTE VENTO

Keyword(s):

Electric Charge ◽

Particle Physics ◽

Magnetic Pole ◽

Experimental Search ◽

Grand Unified Theories ◽

Unified Theories ◽

Discrete Nature ◽

Magnetic Poles ◽

The Universe

Dirac showed that the existence of one magnetic pole in the universe could offer an explanation of the discrete nature of the electric charge. Magnetic poles appear naturally in most grand unified theories. Their discovery would be of greatest importance for particle physics and cosmology. The intense experimental search carried thus far has not met with success. I propose a universe with magnetic poles which are not observed free because they hide in deeply bound monopole–antimonopole states named monopolium. I discuss the realization of this proposal and its consistency with known cosmological features. I furthermore analyze its implications and the experimental signatures that confirm the scenario.

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Semi-adiabatic Curing Test with Heat Loss Compensation for Evaluation of Adiabatic Temperature Rise of Concrete

HKIE Transactions ◽

10.1080/1023697x.2012.10669000 ◽

2012 ◽

Vol 19 (4) ◽

pp. 11-19

Author(s):

P L Ng ◽

A K H Kwan

Keyword(s):

Heat Loss ◽

Temperature Rise ◽

Adiabatic Temperature ◽

Adiabatic Temperature Rise ◽

Loss Compensation

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JOULE HEATING EFFECT REDUCTION OF AN ELECTROMAGNET SYSTEM UTILIZING ON-CHIP MAGNETIC CORE

Jurnal Teknologi ◽

10.11113/jt.v78.9591 ◽

2016 ◽

Vol 78 (8-4) ◽

Cited By ~ 1

Author(s):

Ummikalsom Abidin ◽

Jumril Yunas ◽

Burhanuddin Yeop Majlis

Keyword(s):

Joule Heating ◽

Temperature Rise ◽

Magnetic Core ◽

Operating Conditions ◽

Optimum Operating ◽

Pdms Layer ◽

Heating Effect ◽

Joule Heating Effect ◽

Magnet Wire ◽

On Chip

Joule heating effect is substantial in an electromagnet system due to high density current from current-carrying conductor for high magnetic field generation. In Lab-on-chip (LoC) Magnetically Activated Cell Sorting (MACS) device, Joule heating effect generating high temperature and affecting the biological cells viability is investigated. The temperature rise of the integrated system was measured using resistance temperature detector, RTD Pt100. Three temperature rise conditions which are from the bare spiral-shaped magnet wire, the combination of magnet wire and on-chip magnetic core and combination of magnet wire, on-chip magnetic core and 150 mm polydimethylsiloxane (PDMS) layer have been investigated. The combination of electromagnet of spiral-shaped magnet wire coil and on-chip magnetic core has reduced the temperature significantly which are, ~ 38 % and ~ 26 % with magnet wire winding, N = 10 (IDC = 3.0 A, t = 210 s) and N = 20 (IDC = 2.5 A, t = 210 s) respectively. The reduced Joule heating effect is expected due to silicon chip of high thermal conductivity material enable fast heat dissipation to the surrounding. Therefore, the integration of electromagnet system and on-chip magnetic core has the potential to be used as part of LoC MACS system provided the optimum operating conditions are determined

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Performances Analysis of a Novel Electromagnetic-Frictional Integrated Brake Based on Multi-Physical Fields Coupling

World Electric Vehicle Journal ◽

10.3390/wevj10010009 ◽

2019 ◽

Vol 10 (1) ◽

pp. 9

Author(s):

Kuiyang Wang ◽

Ren He ◽

Jinhua Tang ◽

Ruochen Liu

Keyword(s):

Temperature Rise ◽

Geometric Model ◽

Brake Disc ◽

Coupling Mechanism ◽

Radial Temperature ◽

Electromagnetic Brake ◽

Field Coupling ◽

Reference Vehicle ◽

And Performance ◽

Friction Brake

In this article, a novel electromagnetic-frictional integrated brake is proposed, and its structure and working principle are introduced. The geometric model and mathematical models of integrated brake were established, and the multi-field coupling mechanism of integrated brake were analyzed. With BYD Qin as a reference vehicle, the boundary conditions of thermal load and force load of integrated brake were determined according to its structure and performance parameters. Based on the COMSOL software, numerical coupling calculations of electric, magnetic, thermal, and solid fields of integrated brake were carried out respectively in the emergency and downhill braking at a constant speed. The axial, circumferential, and radial temperature distributions of integrated brake disc were analyzed respectively, and they were compared with those of the traditional friction brake disc. The analysis results show that the proposed integrated brake can effectively improve the heat fading resistance of automotive brake during emergency and continuous braking. Under the two braking conditions, the temperature rise of friction brake was faster than that of an electromagnetic brake, and the effect of the electromagnetic brake on temperature rise of integrated brake was small.

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Modeling of Cutting Temperature in Near Dry Machining

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2162907 ◽

2005 ◽

Vol 128 (2) ◽

pp. 416-424 ◽

Cited By ~ 25

Author(s):

Kuan-Ming Li ◽

Steven Y. Liang

Keyword(s):

Heat Source ◽

Heat Loss ◽

Temperature Rise ◽

Flank Wear ◽

Cutting Temperature ◽

Heat Sources ◽

Dry Machining ◽

Machining Processes ◽

Tool Flank Wear ◽

Dry Cooling

Near dry machining refers to the condition of applying cutting fluid at relatively low flow rates, on the order of 2-100ml∕h, as opposed to the conventional way of using either a large quantity, typically of about 10l∕min, as in wet machining; or no fluid at all, as in dry machining. One important expectation of applying fluids is to control the cutting temperature, which is an important parameter for tool life and part dimensional accuracy in machining processes. In this context, the understanding of cutting temperature variation corresponding to the near dry cooling and lubrication is of interest. This paper models the temperature distributions in the cutting zone under through-the-tool near dry cooling condition. The heat source method is implemented to estimate the cutting temperatures on the tool-chip interface and the tool-workpiece interface. For the temperature rise in the chip, the effects of the primary heat source and the secondary heat source were modeled as moving heat sources. For the temperature rise in the tool, the effects of the secondary heat source, the heat loss due to cooling, and the rubbing heat source due to the tool flank wear, were modeled as stationary heat sources. For the temperature rise in the workpiece, the primary heat source, the heat loss due to cooling, and the rubbing heat source due to the tool flank wear were modeled as moving heat sources. The model describes the dual effects of air-oil mixture in near dry machining in terms of the reduction of cutting temperature through the cooling effect, as well as the reduction of heat generation through the lubricating effect. To pursue model calibration and validation, embedded thermocouple temperature measurement in cutting medium carbon steels with uncoated carbide insets were carried out. The model predictions and experimental measurements show reasonable agreement and results suggest that the combination of the cooling and the lubricating effects in near dry machining reduces the cutting temperatures on the tool-chip interface by about 8% with respect to dry machining. Moreover, the cutting speed remains a dominant factor in cutting temperature compared with the feed and the depth of cut in near dry machining processes.

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