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Glass is a “solid that cooled down after melting to maintain liquid structure”, commonly known as “supercooled liquid”. It belongs to amorphous amorphous material, which is different from gem, ceramics and other crystalline materials. Based on the analysis of the chemical composition data of PIXE, this paper studies the archaeological unearthed objects of different periods in the Central Plains area of pre Qin Dynasty, and compares them with the sample data of Western Asia and Egypt to analyze the development and origin of ancient glass technology in the Central Plains. The results show that the ancient glass in the Central Plains area of pre Qin China sprouted in the Shang Dynasty, based on the faience and frit in the spring and Autumn period of the Western Zhou Dynasty, really appeared at the end of the spring and Autumn period. According to the different auxiliary solvents, it can be divided into three categories: early alkali calcium silicate glass, lead barium glass and potassium silicate Asia, ancient Egypt and their influence on the development of ancient glass technology in the Central Plains during the pre Qin period. According to the different cosolvents, it can be divided into early alkali-calcium silicate glass and lead barium glass. The three categories of potassium silicate and potassium silicate demonstrate the original system and characteristics of ancient glass in the pre-Qin period, and analyze the influence of ancient West Asia, ancient Egypt and the development of ancient glass technology in the Central Plains in the pre-Qin period from the perspective of cultural exchanges between China and the West.

The multi-ethnic indigenous culture, the inclusive Indian religious form and the political concept of the unity of god and king provide the unique aesthetic connotation and humanistic spirit for the development of religious architectural art in Thailand. From the perspective of design aesthetics, this paper intends to analyze the aesthetic dimensions and style characteristics of the Temple of the Dawn Complex, from the three aspects of “Essence”, “Form” and “Content” through field research, combining with literature materials. It explores the cultural symbiosis presented by the diversified features and influencing factors of the decorations in the Temple of the Dawn Complex in Thailand.

Results are described from a series of laboratory experiments in which the effects of a localized two-dimensional region of turbulence on the spatial development of a round, turbulent jet have been investigated. The evolution of the jet has been studied for respective cases with and without background turbulence in the receiving environment. For the former flow configuration, the breakdown of the jet by the presence of background turbulence (generated by an oscillating grid) has been investigated parametrically for a range of values of the source specific momentum flux J0 of the jet and the grid action K. Measurements of the location of the breakdown point of the jet, as detected by (i) a significant local increase in the jet spreading angle and (ii) the simultaneous decrease and increase in the magnitude of the axial and horizontal velocity components, respectively, of the flow field, confirm scaling predictions showing that the jet is destroyed significantly by the background turbulence when the background turbulence intensity is of the same order as the local turbulence intensity of the jet.

The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

An experimental investigation is presented on the large-scale motion field and associated mixing of an initially two-layer, equal depth stratified fluid driven by an impulsively-started, rotating disk at the base of the (cylindrical) fluid container. For sufficiently large Reynolds numbers and fixed geometry, the flow is shown to depend on a single parameter, the Richardson number Ri = g'H/(ωRT)2, where g' is the reduced gravity, H is the depth of each of the fluid layers, and ω and RT are the disk rotation rate and radius, respectively. For Ri < 1.5 the primary mixing mechanism is found to be shear-induced billowing along the primary density interface, with the mixed fluid along this interface being advected into the lower fluid interior by secondary motions. An analysis is advanced to show that the elevation of the interface separating the upper (almost quiescent) layer of constant density from the lower mixed region grows as [Ri−1(H/RT)−1]ωt, where t is the time. The experimental observations are in good agreement with this scaling. The studies reveal that the large-scale secondary motion fields characteristic of this physical system force secondary interfaces, or fronts, to be formed periodically in the lower mixed layer region. These secondary fronts are shown to be relatively weak, with the velocity and density jumps across them being small compared with those across the primary interface.

Results are presented from a series of laboratory experiments in which a flow has been generated in a linearly-stratified fluid (initially at rest in a cylindrical container of radius RT) by the impulsive steady azimuthal rotation of a flat, smooth, horizontal circular disk of radius Rd. Experiments have been conducted for a range of disk sizes Rd, disk rotation rates ω and buoyancy frequencies N0, and the spatial and temporal development of the motion and density fields (and mixing associated therewith) have been shown to be critically dependent on the ratio Rd/RT. For cases in which this ratio is close to unity, the principal mixing mechanisms affecting the flow development are shown to be (i) the localised overturning of fluid forced by the disk Ekman layers and confining sidewalls and (ii) shear-induced billow entrainment along the outer edge of the so-called primary interface between the upper, unmixed fluid and the lower, partially-mixed fluid regions adjacent to the disk. For the large disk case, for sufficiently high values of ω/N0, density gradients develop sequentially with time within the partially-mixed region and the forms of the associated density interfaces also change with time as the primary interface migrates vertically. At the other extreme, for small values of the ratio Rd/RT but otherwise identical external conditions, the container walls play a negligible role in the flow development and the initial mixing is achieved primarily by shear-induced billow overturning at the primary interface. A scaling analysis is advanced to predict the growth rate of the primary interface and the experimental data are shown to be in good agreement with the analysis.

In the present study, the subgrid-scale (SGS) eddy-viscosity model developed by Vreman [Phys. Fluids 16 (2004) 3670] and its dynamic version [Phys. Fluids 19 (2007) 065110] are tested in large-eddy simulations (LES) of the inhomogeneous turbulent flow in a full passage of Francis turbine. Distributions of pressure, velocity and vortices as well as some flow structure are gained, which is helpful to examine the performance of SGS model for complex turbulent flow and understand the flow characters in full passage of Francis turbine.