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The purpose of this paper is to evaluate the possibilities of the particle finite element method for simulation of free surface flows.

A numerical simulation of a number of examples for which experimental data are available is performed. The simulations are run using the same scale as the experiment in order to minimize errors due to scale effects. Some examples are chosen from the civil engineering field: a study of the flow over a flip bucket is analyzed for both 2D and 3D models, and the flow under a planar sluice gate is studied in 2D. Other examples, such as a 2D and 3D “dam break” with an obstacle are taken from the smooth particle hydrodynamics literature.

Different scenarios are simulated by changing the boundary conditions for reproducing flows with the desired characteristics. Different mesh sizes are considered for evaluating their influence on the final solution.

Details of the input data for all the examples studied are given. The aim is to identify benchmark problems for future comparisons between different numerical approaches for free surface flows.

The purpose of this paper is to experimentally and numerically investigate the interference characteristics between two ski-jump jets on the flip bucket in a large dam spillway when two floodgates are running.

The volume of fluid (VOF) method together with the Realizable k-ε turbulence model were used to predict the flow in two ski-jump jets and the free surface motion in a large dam spillway. The movements of the two gates were simulated using a dynamic mesh controlled by a User Defined Function (UDF). The simulations were run using the prototype dam as the field test to minimize errors due to scale effects. The simulation results are compared with field test observations.

The transient flow calculations, accurately predict the two gate discharges compared to field data with the predicted ski-jump jet interference flow pattern similar to the observed shapes. The transient simulations indicate that the main reason for the deflected nappe is the larger opening difference between the two gates as the buttress side gate closes. When both gates are running, the two ski-jump jets interfere in the flip bucket and raise the jet nappe to near the buttress to form a secondary flow on this jet nappe surface. As the gate continues to close, the nappe surface continues to rise and the surface secondary flow become stronger, which deflects the nappe over the side buttress.

A dynamic mesh is used to simulate the transient flow behavior of two prototype running gates. The transient flow simulation clarifies the hydraulics mechanism for how the two ski-jump jets interfere and deflect the nappe.

The paper aims to apply a modified version of the MPS method to a double-dam-breaking test in which high dispersion zones and high natural clusterization zones are present, such as when the water column collapses into two sides and the two solitary waves collide, respectively.

The work takes advantage of the mixed source term from the cheaper computational version of the moving particle semi-implicit (MPS) method to reduce one step from the MPS classical algorithm. The proposed test can be successfully simulated by applying modifications to the variance parameter in the Laplacian operator and gradient model.

The results show stable behavior in dispersion and clusterization zones. Also, the collision and merging produced by solitary waves was successfully simulated.

The main limitation in this work was the development of a comparison between the obtained results and the simulations with the original cheaper computational version of the MPS, this limitation is due to the overestimation of inter particle repulsive forces from its gradient model.

The application of solitary waves is of paramount importance in a number of applications, and this stems from the fact that the interaction of solitary waves with ships and other floating structures could generate highly deformed and complex free surface flows.

For future work, the modified version of the MPS method can be applied in flow over sill base simulations, in close and open channels, and in simulating breaking waves to determine impact pressures by using solitary wave propagation.

The simulation of interaction of large groups of particles as in the case when two solitary waves collide could cause severe instability problems in pressure, causing the computer analysis to stop. MPS classical algorithm takes into account an explicit step that, in this case, may provoke the problem. For this reason, the cheaper version of MPS method is used to correctly simulate solitary wave interactions.

A new roller compacted concrete dam of Fengman hydropower station was determined to be built in the toe of the old dam which had been identified as a dangerous dam. The new dam during construction would be impacted by the high‐speed flow discharged from the old dam. This is an important problem met for the first time in China, which would affect the whole project construction. The purpose of this paper is to describe a series of erosion experiments of the new dam material.

A kind of high‐speed flow erosion test apparatus was developed for erosion experiment of the new dam material. The maximum jet velocity was up to 40 m/s and the section area of the nozzle was 25 cm². In the process of experiments, the equipment showed its good performance. Erosive wear tests of two types of materials used in the new dam, a roller compacted concrete and a distorted concrete with four kinds of ages were carried out with the flow velocity in the range of 30‐35 m/s.

Erosion parameters and erosion laws of the two types of concretes with different ages were obtained, and a general relationship had been found between erosion rate and flow velocity: with velocity exponent between 3.33 and 3.93. It was also concluded that the erosion resistance of the distorted concrete was better than that of the roller compacted concrete and the mechanics properties of the concretes of over 14 days age was influenced slightly by water impacted.

The test results would play a practical technique guide role for the safety of this project during construction in the flood season.

The purpose of this study is to focus on how narratives are used to acquire social venture resources. Social entrepreneurship is a phenomenon of increasing significance. A key challenge for social ventures is resource acquisition. However, how social entrepreneurs gather the resources necessary to grow their organizations is not clear.

This topic is examined using a multi-study, inductive, theory-building design based on 121 interviews, observation and archival data. In Study 1, 75 entrepreneurs, investors and ancillary participants were interviewed in the social enterprise sector. In Study 2, case studies of eight technology-focused social ventures were constructed.

The result of this study is a framework explaining how differences in entrepreneurs’ narrative tactics and characteristics are associated with differences in their resource acquisition success. Specifically, from Study 1, this paper develops a typology of social enterprise narratives, identifies three narrative-types (personal, social-good and business) and shows that they possess unique elements. Evidence from Study 2 suggests that the three narrative-types serve as the building blocks for communication with external stakeholders.

These findings contribute to three studies that formed the basis of the study – social entrepreneurship, entrepreneurial resource acquisition and organizational narrative theory – and have implications for work on competing organizational logics. They also produce several practical implications for social entrepreneurs.

The Japanese culture has many meanings and proverbs associated with the word “water.” “Water” could mean “clear,” “clean,” “beautiful,” and “life.” Water is valuable to people in that it is used for drinking, cooking, washing, and fishing. On the flip side, water is a cause of disaster. Thus, people use water for survival, as well as fight with water during disasters. Because of the many uses of water, people developed a rule for water utilization. This rule cultivated trust in the community. However, infrastructure development (e.g., water supply system, dikes, and road networks), the promotion of washing machines, and social advancement changed the role of the water area from just a flowing stream, which can be simply likened to a sewer, to an important component of infrastructure.

So this is OCLC, where the fixed fields are at the top of the record and you type the first three characters of the title, comma, next two letters, comma, … and here's something that looks familiar, but it's called an M300 Workstation. But here's Microsoft and Lotus 1–2–3! Maybe things aren't so different after all.