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In the electromagnetic field simulation of modern servo drives, the computation of higher time and space harmonics is essential to consider appearing torque pulsations, radial forces and ripple torques. The purpose of this paper is to propose a method to cover the effect of saturation on the armature flux density within conformal mapping (CM) by an finite element (FE) re‐parameterization.

Field computation by CM techniques is a time‐effective method to compute the radial and tangential field components, but it generally neglects the effect of saturation.

This paper presents a method to re‐parameterize the CM approach by single FE computations so as to consider saturation in the model over a wide operation range of the electrical drive.

The proposed method is applied to a surface permanent magnet synchronous machine, and compared to numerical results obtained by finite element analysis (FEA).

The paper shows that an accuracy similar to that of FE simulations can be obtained with still the low‐computation time that is the characteristic of analytical models.

The aim of this paper is to provide basic information on the types of particulate cyclones separators used in the chemical and process industries, their principles of operation and factors affecting their performance.

A general review of the types of particle cleaning cyclones used in the chemical and process industries was carried out and the principles guiding their operation and performance discussed. Information which could aid the choice of cyclone for new applications is also discussed.

It was concluded that the choice of cyclone for any application is associated with a trade‐off between two contrasting performance indicators (collection efficiency and pressure drop). Adequate and accurate data gathering is essential right from the design stage for smooth operation of cyclone.

The paper highlights the general principle of operation of cyclone separators and the factors that affect their performance.

This Symposium reports on the opportunities available to those who take the initiative to introduce materials management approaches. It examines both the anticipate rates of change and development of the underlying factors as well as the organisational implications they entail. A full bibliography of recent literature is provided. The predicted developments are derived from the findings of a Delphi Study in association with the Institute of Purchasing and Supply conducted by the author in 1976.

Water systems in civil aircraft, stimulated by passenger comfort needs, have grown to be a comprehensive and important part of aircraft engineering. In this article, following a review of the system types, the design features arc discussed in detail and emphasis has been placed on the functional and hygiene requirements, and on the need for simplicity and weight conservation. Attempts have been made to augment air‐borne water supplies by reclamation means, but these have not been too successful. Investigations should therefore continue into the ways and means of improving the utilization of existing ‘fixed’ capacity systems. Installation safety aspects are also discussed.

Today, “lean” may no longer be fashionable but its core principles (flow, value, pull, minimizing waste etc.) have become the paradigm for many manufacturing (and service) operations. Given this pre‐eminence, the paper seeks to establish what impact it has had on the overall competitive positions of adopter firms. Combining normative and critical theory (from lean production and resource‐based view of the firm literature) with empirical material drawn from three case studies, the paper argues that lean production can underpin competitive advantage if the firm is able to appropriate the productivity savings it creates. Similarly, the ambiguity of lean production in practice means that the implementation process can create strategic resources to underpin sustainable competitive advantage. Problematically, however, the paper also suggests that being “lean” can curtail the firm’s ability to achieve long‐term flexibility. It concludes with suggestions for further work.

Purpose – Measures aimed at reducing intersection crashes have high potential to be cost effective since intersections constitute only a small part of the overall highway system but intersection-related crashes constitute more than 50% of all crashes in urban areas and over 30% in rural areas. Roundabouts are a proven safety countermeasure, but several issues that significantly affect both crash frequency and severity have been observed at both existing and new roundabouts. This chapter aims to provide guidance on roundabout selection and design criteria.

Methodology – The chapter first describes the most relevant criteria to be considered for choosing a roundabout. Then, after the explanation of the roundabout design process and a clear description of the roundabout classification, the chapter provides recommendations for all the steps of the geometric design, highlighting the main design features that contribute to the best safety performances, including speed control and sight distance checks. Finally, the chapter explains traffic control devices and facilities for pedestrians and cyclists.

Findings – Roundabout design needs to balance opposing demands and it is important to adopt a performance-based design approach within an iterative process. The most important performance check is the analysis of vehicle speeds through the roundabout, since achieving appropriate vehicular speeds has a very positive safety effect.

We describe a novel mathematical approach to deriving and solving covolume models of the incompressible 2‐D Navier‐Stokes flow equations. The approach integrates three technical components into a single modelling algorithm: 1. Automatic Grid Generation. An algorithm is described and used to automatically discretize the flow domain into a Delaunay triangulation and a dual Voronoi polygonal tessellation. 2. Covolume Finite Difference Equation Generation. Three covolume discretizations of the Navier‐Stokes equations are presented. The first scheme conserves mass over triangular control volumes, the second scheme over polygonal control volumes and the third scheme conserves mass over both. Simple consistent finite difference equations are derived in terms of the primitive variables of velocity and pressure. 3. Dual Variable Reduction. A network theoretic technique is used to transform each of the finite difference systems into equivalent systems which are considerably smaller than the original primitive finite difference system.

In order to solve nonplanar LEO‐LEO aeroassisted space rendezvous, this paper aims to study an active phasing method based on orbital preliminary adjusting scheme out of atmosphere.

In order to add atmospheric entry velocity, orbital preliminary adjusting out of atmosphere is presented and the orbital altitude of high earth orbit (HEO) is selected eclectically. Nonplanar HEO‐LEO aeroassisted orbital transfer problem is studied in detail. According to the standard atmospheric flight trajectory, the locations of deorbit points in HEO are determined and the standard phase angle between orbital transfer vehicle (OTV) in HEO and target in low earth orbit (LEO) is obtained so that OTV and target meet space rendezvous demand. Finally, the active phasing method is studied so that the standard phase angle can be satisfied when OTV is transferred to HEO. So space rendezvous can be realized under the help of aeroassisted orbital transfer technique once the standard phase angle is satisfied.

Nonplanar LEO‐LEO orbital transfer depending on entirely propulsive will use enormous fuel and the phasing problem will be most difficult in nonplanar LEO‐LEO space rendezvous mission. However, the fuel consumption can be saved and rendezvous mission can be finished in an advisable time when nonplanar LEO‐LEO aeroassisted orbital transfer technology is applied properly.

Aeroassisted space rendezvous method is presented in this paper. Orbital preliminary adjusting out of atmosphere is studied in order to add atmospheric entry velocity and the active phasing method for realizing space rendezvous is integrated in preliminary adjusting scheme.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The paper seeks to focus on obtaining the transient torque required to rotate the inner cylinder in open ended vertical concentric annuli for a fluid of Pr = 0.7 in the laminar natural convection flow regime over a wide range of the controlling parameter Gr²/Ta. The inner wall is heated and subjected to an impulsive rotation while the outer one is stationary and maintained adiabatic.

The governing transient boundary‐layer equations are numerically solved using an iterative linearized finite‐difference scheme.

The transient induced flow rate and absorbed heat for different annulus heights are presented. High rotational speed (i.e. low values of Gr²/Ta) increases the flow rate and heat absorbed in short annuli. However, for considerably tall annuli, Gr²/Ta has slight effect on the flow and heat absorbed. The steady‐state time is tangibly influenced by Gr²/Ta in considerably short annuli and very slightly affected for considerably tall annuli.

The investigated problem can simulate the start‐up period of naturally cooled small vertical electric motors.

The paper presents results not available in the literature for the effect of Gr²/Ta on the developing velocities, pressure, flow‐rate induced, absorbed heat by fluid and required torque in vertical concentric annuli with impulsively rotated inner walls under the transient free‐convection heat transfer mode.