Three-dimensional stationary magnetic field calculation of permanent magnet systems designed for thermomagnetic engine

Аuthors

Gabrielyan D. A.^*, Semenov V. V.^**

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: david@gbrl.ru
**e-mail: vasily_semenov@mail.ru

Abstract

Purpose

The article aims are development recommendations for choosing the optimal magnetic systems (MS) used in thermomagnetic engines (TME) and solving the problem of its designing by computer simulation.

Design/methodology/approach

All calculations were performed by the finite element method (FEM) using the certified ANSYS Multiphysics 13.0 software package. Calculations are made both in two-dimensional and three-dimensional geometries. Considering magnetostatic calculation results of simplest magnetic system and operation principles of TME, that are based on magnetic phase transitions occurring in some ferromagnetic materials under the influence of the thermal impulse, authors develop recommendations for designing of the optimal magnetic systems. The set of calculations were performed to define a magnetic system that would satisfy these recommendations. Such magnetic system is presented and analyzed in the work.

Findings

Firstly, the calculation data show that the magnetostatic problem can be solved at a qualitative level quite well in the ANSYS software package. Secondly,the choice of permanent magnet (PM) should be guided by, at least, three factors: efficiency (would be good to create the most powerful MS), cost (the cost of the magnet increases with its size and power) and compactness. Thirdly, for performing effective operation of rotary thermomagnetic engine magnetic system have to provide the high values of magnetic induction in the working volume of the magnetic system and distribution of magnetic field has to obtain prolonged and continuous growth of the magnetic induction at the MS entrance and reduce action of magnetic force on the ferromagnetic working substance at the MS output. Such magnetic system was defined (fig.1). 

Fig.1. Defined model of magnetic system

It satisfies all recommendations that were developed by authors of the work and has distribution of magnetic induction along the interpolar gap of MS as shown on a figure 2.Also, the optimizations of the opening angle and of the straight area length of this system were made. It was defined that optimal magnetic system for rotary TME is a system with opening angle α = 24 ÷ 34° and with straight area length l = 10 ÷ 15 mm.

Research limitations/implications

This research provides development of non-traditional methods of mechanical or electrical energy production based on thermomagnetic effects.

Originality/value

There is a lack of magnetic system designing data for thermomagnetic energy devices in literature. In descriptions of such devices simplest magnetic systems are used that have non-appropriate distributions of magnetic field in the working area. So, in recent work, using the computations with ANSYS software, the magnetic system models were optimized and recommendations for it designing were established.

Keywords:

thermomagnetic engine, magnetic system, permanent magnet, magnetostatics, ANSYS, ferromagnetic element

References

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2. Hazelwood J. Patent US 2010/0253181 A1, 07.10.2010.
3. Gabrielyan D.A. Patent RU 118369, 03.05.2012.
4. Andreeva E.G., Shamets S.P., Kolmogorov D.V. Neftegazovoe delo, 2004, available at: http://www.ogbus.ru/authors/Andreeva/Andreeva_1.pdf
5. Bul O.B. Metody rascheta magnitnykh sistem elektricheskikh apparatov. Programma ANSYS (Methods of calculation of magnetic systems of electric devices. ANSYS program), Moscow, Akademiya, 2006, 288 p.