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Radial vibration of horizontal centrifugal pump has a close association with radial exciting forces. The purpose of this paper is to analyze the unsteady radial force in multistage centrifugal pump with double volute in detail and investigate the relevance of static pressure, radial force and radial vibration.

The unsteady numerical simulation with realizable k-ε turbulence model was carried out for a multistage centrifugal pump with double volute using computational fluid dynamics codes Fluent. The performance tests were conducted by use of a closed loop system and performance curves from numerical simulation agree with that of experiment. Vibration tests were carried out by vibration probes instrumented on the bearing cover of pump near no-driven end. Fast Fourier transform was used to obtain the frequency components of radial forces on the impellers from numerical simulation, which are compared with ones of radial vibration from experiment in Y and Z direction. And the static pressure distributions in the impeller were analyzed under different flow rates.

The symmetrical double volute can effectively balance radial forces. The maximum radial force and vibration velocity appear at 0.6 Q among the three flow rates 0.6 Q, Q and 1.2 Q. The frequencies corresponding to relatively large amplitude of vibration velocities and radial forces on the impellers in Y direction are blade passing frequency of the impellers. Blade passing frequency of first-stage impeller and shaft frequency are predominating in Z direction. It indicates that the radial vibration of centrifugal pump is closely related to the unsteady radial force.

The unsteady radial forces of the impeller in multistage centrifugal pump with double volute were comprehensively analyzed. The radial forces should be considered to balance during the design of multistage centrifugal pump.

Climate change is a vortical situation of increasing turbulent conditions called the “sixth extinction.” In this chapter I begin with the two-dimensional Archimedean spiral (the coiling rope), move on to the three-dimensional corkscrew spiral (or threaded screw), and on to the three-dimensional double spiral of upward and descending movement with many nested vortices. The latter is more necessary to understand climate change, and our possible future in it, than the flat spirals. Ironically, Plato wrote about the double-twisted spiral with its nested vortices long ago. We are in a double-spiralic helice, a vortical phenomenon with centripetal and centrifugal, upward-ascending and downward-descending waves, and left and right turning whorls. It is worse than this. We need to challenge spiral symmetry thinking. There is no reality axis around which the spiralic helice is spinning, and there is no symmetry. There is no uniformity to the spiralic vortices of turbulence of the sixth extinction.

This paper aims to study the fluid flow and heat transfer through a spiral double-pipe heat exchanger. Nowadays using spiral double-pipe heat exchangers has become popular in different industrial segments due to its complex and spiral structure, which causes an enhancement in heat transfer.

In these heat exchangers, by converting the fluid motion to the secondary motion, the heat transfer coefficient is greater than that of the straight double-pipe heat exchangers and cause increased heat transfer between fluids.

The present study, by using the Fluent software and nanofluid heat transfer simulation in a spiral double-tube heat exchanger, investigates the effects of operating parameters including fluid inlet velocity, volume fraction of nanoparticles, type of nanoparticles and fluid inlet temperature on heat transfer efficiency.

After presenting the results derived from the fluid numerical simulation and finding the optimal performance conditions using a genetic algorithm, it was found that water–Al₂O₃ and water–SiO₂ nanofluids are the best choices for the Reynolds numbers ranging from 10,551 to 17,220 and 17,220 to 31,910, respectively.

The purpose of this paper is to investigate the influence rule and mechanism of three degrees of freedom film thickness disturbance on the transient performance of spiral groove, upstream pumping spiral groove dry gas seal (UP-SDGS) and double-row spiral groove dry gas seal (DR-SDGS).

The transient performance of spiral groove, UP-SDGS and DR-SDGS are obtained by solving the transient Reynolds equation under different axial and angular disturbance coefficients. The transient and steady performance of the above-mentioned DGSs are compared and analyzed.

The film thickness disturbance has a remarkable impact on the sealing performance of DGS with different structures and the calculation deviations of the leakage rate of the UP-DGS will increase significantly if the film thickness disturbance is ignored. The axial and angular disturbance jointly affect the film thickness distribution of DGS, but there is no significant interaction between them on the transient sealing performance.

The influence mechanism of axial disturbance and angular disturbance on the transient performance of typical SDGSs behavior has been explained by theory. Considering small and large disturbance, the interaction between axial disturbance and angular disturbance on the transient performance have been studied.

The purpose of this study is to propose a fast method for predicting flow fields with periodic behavior with verification in the context of a radial turbine to meet the urgent requirement to effectively capture the unsteady flow characteristics in turbomachinery. Aiming at meeting the urgent requirement to effectively capture the unsteady flow characteristics in turbomachinery, a fast method for predicting flow fields with periodic behavior is proposed here, with verification in the context of a radial turbine (RT).

Sparsity-promoting dynamic mode decomposition is used to determine the dominant coherent structures of the unsteady flow for mode selection, and for flow-field prediction, the characteristic parameters including amplitude and frequency are predicted using one-dimensional Gaussian fitting with flow rate and two-dimensional triangulation-based cubic interpolation with both flow rate and rotation speed. The flow field can be rebuilt using the predicted characteristic parameters and the chosen model.

Under single flow-rate variation conditions, the turbine flow field can be recovered using the first seven modes and fitted amplitude modulus and frequency with less than 5% error in the pressure field and less than 9.7% error in the velocity field. For the operating conditions with concurrent flow-rate and rotation-speed fluctuations, the relative error in the anticipated pressure field is likewise within an acceptable range. Compared to traditional numerical simulations, the method requires a lot less time while maintaining the accuracy of the prediction.

It would be challenging and interesting work to extend the current method to nonlinear problems.

The method presented herein provides an effective solution for the fast prediction of unsteady flow fields in the design of turbomachinery.

A flow prediction method based on sparsity-promoting dynamic mode decomposition was proposed and applied into a RT to predict the flow field under various operating conditions (both rotation speed and flow rate change) with reasonable prediction accuracy. Compared with numerical calculations or experiments, the proposed method can greatly reduce time and resource consumption for flow field visualization at design stage. Most of the physics information of the unsteady flow was maintained by reconstructing the flow modes in the prediction method, which may contribute to a deeper understanding of physical mechanisms.

Chester Street, Aston, Birmingham, 6. The ‘Donald’ Patent Barrel Lifter Truck and Stand, the three‐in‐one appliance. Barrels up to 7 cwts. lifted and transported by one man. ‘Donald’ Patent Barrel Lifter Stands for Oil Stores.

The evolution of capitalism has gone through four major epochs, from the first tangible exchanges of goods and resources, to the generation of wealth by entrepreneurs held personally accountable for their actions, to cost-cutting measures for increasing efficiencies and maximizing wealth for the few, and finally to a socially irresponsible form. The fourth epoch dispatched the last remaining shards of capitalist responsibility to anyone but investors, as the basis of wealth appropriation shifted to manipulating the speculative future worth of intangible or fictitious capital. This evolution through four epochs has sadly been a process of diminishing value creation (Boje et al., 2017).

We are trapped in an era of socially irresponsible capitalism with little respect for humankind. But, it was not always this way. The earliest references to entrepreneurial behavior emerged in the east during the Han Dynasty and in the west in the eighteenth century. Somewhat like the fourth epoch of the twenty-first century, these global beginnings of early capitalism were also directed by opportunistic desires to pursue wealth generation by taking advantage of people’s needs and wants. Although capitalists have consistently been the prime directors of resources and the distributors of wealth, in the early epochs of capitalism they were different. The early epoch entrepreneurs bore personal risks of business failure, consequences that might impact them for a lifetime.

The antenarrative generative mechanisms, or spirals, help us understand the interconnectivities of “real” and “actual” domains of reality (Bhaskar, 1975; Boje, 2016). Socially irresponsible capitalism is pulling global societies into a downward spiral toward an addiction of speculative destruction and dehumanization, transforming “real” into “actual” realities. We need a force to pull us back up toward a revitalized form of socially responsible capitalism. This force is called the socio-economic approach to management (SEAM), and in the responsible entrepreneurial spirit of earlier epochs, the path to recovery can be accomplished by accountably working with one organization or entity at a time.

This chapter first investigates the historical double-spiral-helix footsteps of socially irresponsible capitalism in the making. Then through a SEAM project example, we discuss how the micro-societal perspective of an organization places it at a deeper level of reality, deeper within the double-spiral-helix meta-reality of macro-societal capitalism. Finally, we demonstrate how the socioeconomic approach can help diagnose the deeper realities with an organization, beyond the evident narratives, to reveal the third spiral of deficiencies. This third spiral disenables the organization’s ability to activate the micro forces of socially responsible capitalism.

This paper aims to investigate the experimental behavior and the reliability of concrete columns repaired using fiber-reinforced polymers (FRPs) under axial compression loading. The expression of the ultimate axial resistance was assessed from the experimental data of damaged concrete cylinders repaired by externally bonded double-FRP spiral strips.

The tested columns bearing capacity mainly depends of the elasticity modulus of both damaged and undamaged concrete have been considered in addition to the applied load and the cylinder diameter as random variables in the expression of the failure criterion. The reliability indicators were assessed using first order second moment method.

The emphasized test results, statistically fitted show that the strength has been retrofitted for all repaired specimens whatever the degree of initial damage. However, the gain in axial strength is inversely proportional to the degree of damage.

The efficiency of a new FRP repair procedure using double-spiral strips was studied. This research provides a technical and economical solution for retrofitting existing concrete columns. Finally, the random character of the variables that govern the studied system shows the accuracy and safety of the proposed original design.

The purpose of this paper is to introduce the development of a knowledge management system. It allows the creation of new knowledge, its consolidation, distribution and combination in the field of educational innovation, in such a way that the knowledge is transferred from individuals to the organisation and from the organisation to individuals. To achieve this, the knowledge spirals of Nonaka are integrated. The epistemological spiral is used to obtain the ontologies that feed the ontological spiral.

More than 600 university teachers participated in the research and the development of the management system, in which more than 400 educational innovation experiences and 1,100 authors have been included.

The epistemological spiral is used to obtain the ontologies that feed the ontological spiral. The result is a double spiral that allows the contribution of a conceptual model and the development of an innovative tool that enables and automates the effective management of knowledge in educational innovation.

A repository about educational innovation best practices and experiences is available.

The presented model for the sustainability and evolution for an educational innovation best practices repositories has a huge impact for education innovation recognition in the professional development of university teachers. On the other hand, it is way of sharing best practices of educational innovation all over the world.

The major contribution of this research work is based on the way that the knowledge is transferred from individuals to the organisation and from the organisation to individuals. The classification schema and the proposed indicators are based on the elicitation of more than 600 experts and the study of a corpus of more than 400 educational innovation experiences that involve 1,100 university teachers approximately.