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Article
Publication date: 11 October 2020

Zhu Feng, Shaotao Zhi, Xuecheng Sun, Lili Yan, Cui Liu and Chong Lei

This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

Abstract

Purpose

This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

Design/methodology/approach

The GMI sensor contains a Co-based internal magnetic core fabricated by laser cutting and an external solenoid. The influences of magnetic permeability of magnetic core and structure parameters on GMI effect were calculated in theoretical model. The output impedance, resistance, reactance and GMI ratio were measured by non-contact method using impedance analyzer.

Findings

Enhancing external magnetic field intensity can decrease the magnetic permeability of core, which has vital influences on the magnetic property and the output response of GMI sensor. In addition, increasing the width of magnetic core and the number of solenoid turns can increase the maximum GMI ratio. The maximum GMI ratio is 3,230% with core width of 6 mm and solenoid turns of 200.

Originality/value

Comparing with traditional contact-measured GMI sensor, the maximum GMI ratio and the magnetic field sensitivity are improved and the power consumption is decreased in non-contact measured GMI sensor. GMI sensor measured by non-contact method has a wide range of potential applications in ultra-sensitive magnetic field detection.

Details

Sensor Review, vol. 40 no. 6
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 11 October 2011

Ntshengedzeni S. Mamphweli and Edson L. Meyer

The purpose of this paper is to develop a cyclone with an internal electric field to capture dust and fine carbon particles with less than 5 μm diameter.

Abstract

Purpose

The purpose of this paper is to develop a cyclone with an internal electric field to capture dust and fine carbon particles with less than 5 μm diameter.

Design/methodology/approach

The cyclone collection efficiency model described by Cooper and Alley was used to design a conventional cyclone, which was later modified by introduction of the solenoid around it to introduce an electric field. The cyclone design performance was later established using ferrosilicon powder with less than 5 μm diameter.

Findings

The cyclone was found to have a particle collection efficiency of around 25 per cent for ferrosilicon powder before the introduction of the solenoid; the introduction of the solenoid increased the particle collection efficiency to around 50 per cent and the charging of the solenoid further increased the collection efficiency to 85 per cent at 2 kV DC and 97 per cent at 3 kV DC. When the cyclone was placed back on the gasifier system and supplied with 2 kV DC, it collected up to 270 g of fine carbon particles within 150 min of operation.

Research limitations/implications

The major drawback was that the highest particle collection efficiency for the cyclone could only be achieved at very high voltage (3 kV) but this could not be supplied when the cyclone was back in the gasifier system due to air ionization that results in the corona effect.

Practical implications

The collection of very fine particles (less than 5 μm diameter) in hot gas streams is always a challenge, particularly in biomass gasifier systems. This resulted in a high cost of gas purification or initial investments in downstream processes. The developed cyclone could cut down this expenditure since most of the particles will not go beyond the cyclone.

Originality/value

Electrostatics has been applied in the development of gas cleaning devices, however most of these devices tend to be too cumbersome. The developed cyclone is based on the conventional design, which is less complicated and cheap to manufacture.

Details

Journal of Engineering, Design and Technology, vol. 9 no. 3
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 24 February 2012

Shigeru Inui, Tatsuro Yamada, Yosuke Horiba and Minoru Hashimoto

In the trend from mass production to mass customization, more flexible production systems are required. In the clothing field, many studies about automatization of sewing…

Abstract

Purpose

In the trend from mass production to mass customization, more flexible production systems are required. In the clothing field, many studies about automatization of sewing processes have been done into producing small amounts of various kinds of products. The purpose of this paper is to propose a versatile guiding mechanism of a cloth for an automatic sewing system.

Design/methodology/approach

Real sewing processes were referenced for the mechanism, and curved stitch is formed holding a point on a cloth. This mechanism consists of a solenoid for holding a cloth and a roller to prevent deformation of the cloth. When a cloth is sewn with the mechanism, the trajectory of the stitch is unstable because of anisotropy of a cloth. A precise trajectory was obtained by adding a device to control the pressure of the roller for holding a cloth and keeping a tension properly applied to a cloth.

Findings

It was found out that shearing property is the most related to the stability of sewing trajectory. If the tension for guidance applied to a cloth is constant, deformation of the cloth was observed and it was the cause of unstableness of sewing trajectory. By controlling the tension for guidance applied to a cloth properly according to the direction of the cloth, precise sewing trajectory was obtained.

Originality/value

There have been some studies in which sewing conditions were dynamically controlled according to the mechanical properties of a cloth. To these studies, here it was proposed that sewing conditions were kept constant by controlling the guidance of a cloth according to its mechanical properties.

Details

International Journal of Clothing Science and Technology, vol. 24 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

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Article
Publication date: 2 January 2009

Jens Benecke and Stefan Dickmann

The purpose of this paper is to compare several methods to calculate solenoid inductances regarding their applicability to model the inductance of DC motor armature…

Abstract

Purpose

The purpose of this paper is to compare several methods to calculate solenoid inductances regarding their applicability to model the inductance of DC motor armature windings. Special attention is given to the influence of wiring insulation and current distribution and the axial length of the solenoid.

Design/methodology/approach

Expressions for the self‐ and mutual‐inductance of current filament and wire combinations are derived from basic inductance formulas. Combining these expressions allows expressing the inductance of arbitrary shaped solenoids (e.g. polygons).

Findings

Accurately describing self‐ and mutual‐inductances is a very complex topic. However, in the case of motor armature windings, several simplifications can be applied to lower the calculation cost significantly. Plus, differences in inductances between regular polygonial solenoids and similar circular shapes were found to be rather small. Thus, many windings' inductances can well be approximated by using expressions for circular solenoids.

Originality/value

A new way to calculate the inductance of arbitrary polygonial shapes is presented, and an example is given for hexagonal shapes.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 28 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 1 February 1951

In a constant speed, variable pitch propeller an over‐ride device is automatically brought into operation to move the blades to the feathering position when the power unit…

Abstract

In a constant speed, variable pitch propeller an over‐ride device is automatically brought into operation to move the blades to the feathering position when the power unit stops, and means are provided by which the over‐ride is automatically put out of action when an attempt is made to start the power unit by ‘wind‐milling’, and by which the over‐ride is automatically restored when the speed rises to that at which the unit should be self‐operating. When the power unit stops a governor 23 allows a spring 22 to force a valve 19 to the left, thereby allowing motive fluid from a pipe 12 to flow into the left‐hand end of a cylinder 16 to operate a plunger 15 which moves the propeller blades 13 to the minimum pitch position. The resultant change of torque acting on a torque meter 39 closes a switch 37 to complete an electrical circuit for actuating a solenoid 35 controlling a valve 34 which allows motive fluid to be applied from pipe 31 to the spring‐loaded plunger 28 of the over‐ride device. The plunger moves the valve 19 to the right, allowing fluid into the right‐hand end of cylinder 16, thereby moving the blades to the feathering poistion. The circuit may also be completed by the pilot closing the fuel isolator valve 36. To start the power unti by wind‐milling, ignition switch 46 of the power unit is closed, the govenor controlled switch 47 being already closed. A solenoid 45 then opens a switch 44 and breaks the circuit to the solenoid 35 so that the valve 34 closes to cut‐off the supply of fluid to the over‐ride plunger. The spring 22 is thus able to move the valve 19 to the left with the result that the blades are moved from the feathered position to cause ‘wind‐milling’. If at a predetermined speed the unit does not then become self‐operating, its governor will open the switch 47 causing switch 44 to close to complete the circuit to the solenoid 35. The valve 34 will be raised to bring the over‐ride into operation, causing plunger 28 to move valve 19 so that the propeller blades are moved to the feathered position.

Details

Aircraft Engineering and Aerospace Technology, vol. 23 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 September 1946

An actuating unit for an aircraft remotely controlled element, comprising a motor including a drive shaft and a pair of field coils for rotating said shaft in opposite…

Abstract

An actuating unit for an aircraft remotely controlled element, comprising a motor including a drive shaft and a pair of field coils for rotating said shaft in opposite directions, an output shaft, complemental jaw clutch elements between said shafts, said clutch elements being adapted to be engaged to establish the driving relation between said shafts and disengaged to break the driving relation, a solenoid controlling said jaw elements, a solenoid switch for each of said field coils, a pair of spaced limit switches operatively connected to said solenoid and solenoid switches, a member movable between said limit switches to actuate one or the other, means drivably connected to said output shaft to cause movement of said member to engage one of said limit switches after a predetermined number of revolutions of said output shaft, contact means included in the circuit of said solenoid switches, and means to control said contact means from said jaw clutch elements whereby engagement of said clutch elements makes the contact and disengagement of the clutch elements breaks the contact.

Details

Aircraft Engineering and Aerospace Technology, vol. 18 no. 9
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 January 1992

N A Al‐Anani and Jewell D GW Howe

Due to their high magnetizing field requirement, the emergence of rare‐earth based permanent magnets is creating onerous demands on the capacitor‐discharge systems which…

Abstract

Due to their high magnetizing field requirement, the emergence of rare‐earth based permanent magnets is creating onerous demands on the capacitor‐discharge systems which are used for their initial magnetization, a process which is aggravated by the fact that the transient current pulse induces eddy currents, which inhibit the penetration of the magnetizing field, and causes heating and stressing of the magnetizing fixture. The problems are compounded in multi‐pole and post‐assembly magnetization systems, particularly for fine pole‐pitch fields. However this paper concentrates on the pre‐magnetization of magnets in air‐cored solenoids, which, despite the difficulty in subsequently handling magnetized magnets, remains the most common requirement. It presents a methodology for the design of impulse magnetizing solenoids to produce the amplitude and time to peak of magnetizing field required for a specific generic type and aspect ratio of magnet to be magnetized, and describes a procedure for the subsequent analysis of the complete impulse magnetization system.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 March 2002

P. Di Barba

The multiobjective optimization of an eight‐block actively‐shielded solenoid has been performed. After a study of each objective function for simplified configurations, up…

Abstract

The multiobjective optimization of an eight‐block actively‐shielded solenoid has been performed. After a study of each objective function for simplified configurations, up to three objectives in mutual contrast and 16 design variables have been considered for the full model. In order to obtain a set of equivalent optimal solutions, an evolution strategy of lowest order with a multistart grid has been linked to a Pareto sorting algorithm. Sparsity in both design and objective space and the improvement of all objectives is a feature of the solutions belonging to the Pareto optimal set.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 21 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Content available
Article
Publication date: 1 August 1998

Abstract

Details

Anti-Corrosion Methods and Materials, vol. 45 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Content available
Article
Publication date: 1 February 2002

Abstract

Details

Anti-Corrosion Methods and Materials, vol. 49 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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