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High speed axial flow pumps are widely used in aircraft fuel systems. Conventional axial flow pumps often generate radial secondary flows at partial-load conditions which influence the flow structure and form a “saddle-shaped” region in the Q-H curve that can destabilize the operation. Thus, the “saddle-shaped” Q-H region must be eliminated. The paper aims to discuss these issues.

The swept stacking method is often used for radial flow control in turbo-machinery impeller blade design. Hence, this study uses the swept stacking method to design a high speed axial flow pump. The detached eddy simulation method and experiments are used to compare the performance of a swept blade impeller in a high speed axial fuel pump with the original straight blade impeller. Both the pump performance and internal flow characteristics are studied.

The results show separation vortices in the impeller with the straight blade design at partial-load conditions that are driven by the rotating centrifugal force to gather near the shroud. The swept geometry provides an extra force which is opposite to the rotating centrifugal force that creates a new radial equilibrium which turns the flow back towards the middle of the blade which eliminates the vortices and the “saddle-shaped” Q-H region. The swept blade impeller also improves the critical cavitation performance. Analysis of the pressure pulsations shows that the swept blade design does not affect the stability.

This study is the initial application of swept blades for axial flow liquid pumps. The results show how the swept stacking changes the radial equilibrium of the high density, high viscosity flow and the effects on the mass transfer and pressure pulsations. The swept blade effectively improves the operating stability of high speed fuel pumps.

The evaluation of eddy currents in cylindrical geometries is examined analytically by using a method, which utilises the second order magnetic vector potential. As an example the three‐dimensional problem of the calculation of eddy currents inside a long conducting cylinder excited by a saddle shaped coil is studied.

Residual thermal stresses and distortion are frequently present in the parts built using a layer‐by‐layer solid freeform fabrication techniques assisted with a moving laser source. This study uses finite element analysis to investigate the effect of laser scanning patterns on residual thermal stresses and distortion. It is shown that the out‐of‐plane distortion of a layer, processed by a moving laser beam can be minimized with a proper selection of the laser scanning pattern. A scanning pattern having changes in its scanning direction frequently by 90° at every turn can lead to the cancellation of concave upward and downward distortions. As a result of this cancellation, very small distortion is present in the laser processed plate. It is also found that distortion is mainly caused by transient thermal stresses rather than residual thermal stresses.

This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata process, closure time and thickness evolution mechanism of the frozen wall.

In this paper several laboratory model tests were conducted, considering different groundwater seepage rate.

The results show that there is a significant coupling effect between the cold diffusion of artificial freezing pipes and groundwater seepage; when there is no seepage, temperature fields upstream and downstream of the gravel strata are symmetrically distributed, and the thickness of the frozen soil column/frozen wall is consistent during artificial freezing; groundwater seepage causes significant asymmetry in the temperature fields upstream and downstream of the gravel strata, and the greater the seepage rate, the more obvious the asymmetry; the frozen wall closure time increases linearly with the increase in the groundwater seepage rate, and specifically, the time length under seepage rate of 5.00 m d⁻¹ is 3.2 times longer than that under no seepage; due to the erosion from groundwater seepage, the thickness of the upstream frozen wall decreases linearly with the seepage velocity, while that of the downstream frozen wall increases linearly, resulting in a saddle-shaped frozen wall.

The research results are beneficial to the optimum design and risk control of artificial freezing process in gravel strata.

The purpose of this paper is to achieve a very accurate localization of hidden metallic objects in human medicine applications.

The proposed methodology takes advantage of the eddy current effect within a metallic object. Its magnetic reaction field will be measured, e.g. with giant magnetic resistor (GMR) sensors.

A comparison of measurements and numerical results obtained by finite element computations demonstrate the reliability and positively gives a clue about the feasibility of the suggested method.

While measuring noisy signals, the use of a lock‐in amplifier is rather expensive; especially, in applications with a high number of GMR sensors the use of channel multiplexer must be considered, which again may generate noise.

The paper shows how appropriate shielding of external fields in the measurement setup ensures results of satisfying quality.

This paper aims to develop an efficient two‐variable minimisation algorithm and to apply it in engineering optimisation of buttonhole reinforcements.

An iterative extreme search is based on quadratic approximation of objective function, locating approximate solution at the minimum of corresponding elliptic paraboloid. Stress analysis is performed using plane stress finite element model. Optimal selection of geometrical parameters of buttonhole‐type reinforcement is done in terms of balance between maximum stress and material consumption.

Adopted minimisation algorithm is assessed in a selected test example and proven to perform well in comparison with methods available in literature. In the selected case two local minima have been found within the predefined optimisation domain, with slight difference in objective function values.

Research is limited to homogeneous isotropic elastic model and a single representative load case. Objective function is restricted to two influence factors and predefined optimisation domain.

The method can be useful for engineers/practitioners in the branch of clothing technology as a tool for computational estimate of optimal design of structural reinforcements.

The main quality of the paper is in software fusion of finite element analysis and advanced optimisation algorithm. The proposed theoretical‐numerical model is discussed in terms of applicability in parameter setting on buttonholer in garment production.

The purpose of this paper is to establish the mathematical foundations of magnetic measurement methods based on translating-coil and rotating-coil magnetometers for accelerator magnets and solenoids. These field transducers allow a longitudinal scanning of the field distribution, but require a sophisticated post-processing step to extract the coefficients of the Fourier–Bessel series (known as pseudo-multipoles or generalized gradients) as well as a novel design of the rotating coil magnetometers.

Calculating the transversal field harmonics as a function of the longitudinal position in the magnet, or measuring these harmonics with a very short, rotating induction-coil scanner, allows the extraction of the coefficients of a Fourier–Bessel series, which can then be used in the thin lens approximation of the end regions of accelerator magnets.

The extraction of the leading term in the Fourier–Bessel series requires the solution of a differential equation by means of a Fourier transform. This yields a natural way to de-convolute the measured distribution of the multipole content. The author has shown that the measurement technique requires iso-parametric coils to avoid interception of the longitudinal field component. The compensation of the main signal cannot be done with the classical arrangement of search coils at different radii, because no easy scaling law exists. A new design of an iso-perimetric induction coil has been found.

In the literature, it is stated that the pseudo-multipoles can be extracted from field computations or measurements. While this is true for computations, the author shows that the measurement of the field harmonics must be done with iso-parametric coils because otherwise the leading term in the Fourier–Bessel series cannot be extracted.

The author has now established the theory behind a number of field transducers, such as the moving fluxmeter, the rotational coil scanner and the solenoidal field transducer.

This paper brought together the known theory of the orthogonal expansion method with the methods and tools for magnetic field measurements to establish a field description in accelerator magnets.

This study seeks to introduce the concept of collectivism, and to assess its impact on interfirm commitment in both high and low collectivist countries.

In evaluating the effects of bilateral power structures on commitment, the paper utilizes polynomial regression and the response surface approach.

Collectivism influenced a manufacturer's commitment to the relationship with its supplier only in Korea, but collectivism did not influence a manufacturer's commitment to the relationship with its supplier in the USA. On the other hand, for the USA sample, significant main effects of manufacturer power and supplier power, as well as a significant interaction between manufacturer power and supplier power on interfirm commitment were detected.

The results demonstrate that the bilateral power magnitude between a manufacturer and its supplier was germane to the manufacturer's commitment. An increase in the supplier's power contributes to manufacturer's commitment, particularly under high bilateral power conditions. Under low bilateral power conditions, manufacturers were shown to become less committed to a relationship.

It is important for global companies to understand the prevailing national culture. US companies operating in Eastern countries, such as Korea, should consider these cultural differences and manage their interfirm relationships on the basis of their long‐term perspectives.

This study facilitates a greater understanding of the influence of national culture on inter‐organizational commitment. Specifically, it evaluates the relative influences of collectivism and interfirm power structures on interfirm commitment in both high and low collectivistic cultures.

The purpose of this paper is to analyze the available literature on the relationship between servitization strategy and firm performance, which identifies the main streams and theoretical foundations of research and provides guidelines for future research in this area.

The paper discusses the relationship between servitization strategy and manufacturing firm performance by gathering and analyzing existing research published between 1988 and 2019 through bibliometric analysis and content analysis, and then unpacking the processes and impacts servitization has on firm performance.

This paper analyzes the evolution of the concept and servitization strategy of manufacturing organizations, and the relationship between servitization strategy and manufacturing company performance. Then, the authors establish an integrated theoretical framework aimed at conveying the factors and providing a practical reference.

The paper establishes an integrated theoretical framework on servitization and firm performance. The results of the systematic analysis of the literature can be used to inform managers about implementing servitization. Managers need to measure the benefits of servitization from two aspects: financial performance and non-financial performance. And managers need to consider some internal and external influencing factors to achieve a strategic–environmental–organizational fit that will bring better benefits to the firm.

The paper contributes to the existing research in three different ways. First, the study perfects the gap of research on the range of all of the factors within the relationship between servitization strategy and manufacturing company performance. Second, the study demonstrates a clear indication of how existing studies’ differences influence the research outcomes. Third, this paper proposes research problems and future research directions.

Interface distinct two-phase computational fluid dynamics (CFD) simulations require accurate tracking in surface curvature, surface area and volume fraction data to precisely calculate effects such as surface tension, interphase momentum and interphase heat and mass transfer exchanges. To attain a higher level of accuracy in two-phase flow CFD simulations, the intersection marker (ISM) method was developed. The ISM method has cell-by-cell remeshing capability that is volume conservative, maintains surface continuity and is suited for the tracking of interface deformation in transient two-phase flow simulations. Studies of isothermal single bubbles rising in quiescent water were carried out to test the ISM method for two-phase flow simulations.

The ISM method is a hybrid Lagrangian–Eulerian front tracking algorithm which can model an arbitrary three-dimensional surface within an array of cubic control volumes. Fortran95 was used to implement the ISM method, which resulted in approximately 25,000+ lines of written code and comments. To demonstrate the feasibility of the ISM algorithm for two-phase flow simulations, the ISM algorithm was coupled with an in-house CFD code, which was modified to simulate two-phase flows using a single fluid formulation. The constitutional equations incorporated terms of variable density and viscosity. In addition, body force source terms were included in the momentum equation to account for surface tension and buoyancy effects.

The performance of two-phase flow simulations was benchmarked against experimental data for four air/water bubbles with 1, 2.5, 5 and 10 mm of diameter rising in quiescent fluid. A variety of bubble sizes were tested to demonstrate the accuracy of the ISM interface tracking method. The results attained were in close agreement with experimental observations.

The results obtained show that the ISM method is a viable means for interface tracking of two-phase flow CFD simulations. Other applications of the ISM method include simulations of solid–fluid interaction and other immersed boundary flow problems.

The ISM method is a novel approach to front tracking, and the results shown are original in content.