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The purpose of this study is to improved the efficiency of condensing steam turbines by legitimately reforming the flow structure. It is of great significance to study the condensation flow characteristics of wet steam for optimizing the operation of condensing steam turbines.

A two-fluid model was used to study the wet steam flow in a stator cascade. The effects of the inlet temperature and pressure drop on the cascade performance were analyzed. On this basis, endwall protrusion models were set up at varied axial position on the pressure surface to evaluate the wetness control and loss under different design conditions for cascade optimization.

The analysis indicates that increasing the inlet temperature or decreasing the pressure drop can effectively control the steam wetness but increase the droplet radius. The increasing inlet temperature can delay the condensation and alleviate the deterioration of the aerodynamic performance of cascades. The non-axisymmetric endwall can significantly affect the distribution of steam parameters below its height and slightly reduce the droplet radius. Compared with the original stator cascade, the optimum design conditions reduce the steam wetness by 8.07 per cent and the total pressure loss by 6.91 per cent below a 20 per cent blade height.

These research results can serve as a reference for condensing steam turbine wetness losses evaluation and flow passage optimization design.

It is well known that alloys, based on iron, were exposed to steam oxidation environment producing thick and non-protective oxide scale. More expensive stainless steels contain more Cr and are able to form more protective scales. The purpose of this research was to show ability to employ nitride coating on different alloys (T23, T91, E1250, 347HFG and HR3C) in order to enhance steam oxidation resistance.

The alloys were exposed to steam oxidation rig. Before the test, furnace was purged by nitrogen in order to remove moisture and oxygen. Di-ionised water was pumped from the reservoir using a peristaltic pump into the furnace. System was kept in the closed circle. To reduce solubility of oxygen, di-ionised water was constantly purged by nitrogen. The total exposure time was 2,000 h at 650°C under 1 bar pressure.

Due to the research, it was found that plasma nitriding process is detrimental for the protection of high-temperature structured materials; the high concentration and high activity of Cr produced a CrN phase. This phase is not stable in steam environment and underwent oxidation to Cr₂O₃ and further into volatile phase (CrO₂(OH)₂). Therefore, austenitic steels (E1250, 347HFG and HR3C) coated with nitride coating deposited by plasma nitriding process suffered similar degradation as the uncoated low Cr ferritic steel.

The main limitation of the research conducted in this study was corrosion resistance of the exposed materials.

To the best of the authors' knowledge, this report is the first of its kind to present nitrided alloys (ferritic and austenitic) exposed in steam oxidation.

The work described in this paper is part of a current programme that has two objects: (1) to investigate further the reasons for the different scaling behaviour of steel in steam and carbon dioxide, although these gases have similar oxygen potentials; (2) to provide background information for an investigation into the effect of variations in re‐heating furnace atmospheres upon scaling and scale adhesion.

The purpose of this paper is to examine science, technology, engineering, art and mathematics (STEAM) efforts at Florida Atlantic University’s (FAU) John D. MacArthur Campus Library (JDM) to share methodologies and ideas with other academic libraries. Recently, there has been an emphasis on and push for science, technology, engineering and mathematics (STEM) education in colleges and universities across the USA as a means for training future work forces and for remaining competitive in global job markets (Land, 2013). FAU in South Florida is a big proponent of STEM and STEAM education (Florida Atlantic University, 2012; Dorothy F. Schmidt College of Arts and Letters, 2013).

As many librarians and outreach staff strive to remain relevant to their faculty and students with changing technologies (Drewes and Hoffman, 2010), the FAU JDM outreach staff have developed several novel programs that are geared toward the STEAM initiative.

The Library Outreach Committee at FAU was committed to investigating how they could advance student success through visual arts programming. How can the library help contribute to STEAM education for the students and learning community as a whole? How can the library engage art students? Can the library promote dialogue in arts to the faculty and staff, regardless of their disciplines? This article will describe and discuss the various art outreach programs that the JDM has tested and their outcomes addressing goals toward STEAM education and academic libraries.

The objective in sharing the experiences at the JDM is to spark new and successful program ideas at other academic libraries across the country and abroad and create knowledge in this relatively new area.

Industries, especially power plants, using steam as power fluid employ many equipment and systems using saturated steam. Mathematical modeling of this saturated steam water space (SSWS) equipment is important for simulators catering to these industries and power plants. Single-equation-based modeling approach and its optimized version, mass factor–volume factor approach, are very efficient in modeling SSWS with bounded volumes, where the volume of the space is fixed. In unbounded volumes, the volume may be changing or is unbounded because of expansion, contraction or pressure control. The purpose of this paper is to propose a single equation based modeling approach for unbounded SSWS. Such unbounded volumes are encountered in coolant channels of pressurized heavy water reactor (PHWR)-type nuclear power plants (NPPs).

This paper proposes an extension of a single-equation approach by considering a subsection of the volume as miniature Point SSWS. In the proposed Point SSWS, the total heat, mass and volume of the SSWS are delinked and overall density and heat density are introduced in place. With this extension, Point SSWS can be applied to unbounded volumes.

In this study, 392 coolant channels of proposed 680 MWe PHWR have been simulated to ascertain the overall coolant density when coolant boils partially on nuclear heating. The simulation results have been compared with simulation results available from previous researchers and it has been found that the values are in line with previous researchers with maximum deviation of 1.2 per cent.

From the simulation results and their low value of deviation, it is clear that point space approach can be effectively used in modeling Point SSWS. Moreover, theoretically, it has been proved that the density of homogenous steam–water mixture is dependent only on the bulk heat density and temperature of the mixture.

Steam contamination (solid particles in the superheated steam) comes from the boiler water largely in the carry‐over of water droplets. The need for extreme purity of steam for use in high pressure turbines has prompted the development of highly satisfactory devices for separating steam and water in a boiler drum. Consequently, steam contamination has been steadily reduced. Troublesome turbine blade deposits may occur with surprisingly low (0.6 ppm) total solids contamination in steam. In the 3.5–6 MPa range, however these deposits are usually water soluble and can be removed by periodic washing. In the 4 to 10 MPa range, however, silica deposits predominate and these deposits are not easily removed by water washing. With operating pressure of 13 MPa and above insoluble deposits do occur which may be controlled by residual water washing. Before the unit is returned to service, the deposits should be removed by air or water‐driven turbine cleaners or by chemical cleaning.

The aim of the study is to compare the effect of steaming method and time on the physico‐chemical properties of underutilized Dioscorea dumetorum with three more commonly consumed Dioscorea rotundata, Dioscorea cayenensis and Dioscorea alata.

Raw and pre‐gelatinized flour were produced from the yam species. Pre‐gelatinization was done by steaming diced cubes in autoclave at 68,950 Nm‐2 for 5 min and in Barlett steamer at 98±2°C for 10, 20 and 30 min. Flour samples were analyzed for amylose content, swelling index, consistency, solubility, water absorption capacity, and iodine affinity for starch.

The physico‐chemical properties of the flours were affected by both species and steaming time. Pre‐gelatinization of the tuber reduced amylose content in all the yam species, which reduced further with increase in steaming time. Except for amylose content and iodine affinity for starch, D. dumetorum compared with D. rotundata and D. cayenensis in the parameters that were measured. Samples autoclaved for 5 min had value similar to those steamed in Barlett steamer for 10 and 20 min for all the parameters that were measured, except consistency.

It is very important to encourage the cultivation and utilization of D. dumetorum because of the high yield and nutritional composition to enhance the nutritional and financial well‐being of the populace.

Pre‐gelatinization is important as pre‐treatment for yam tubers. Underutilized D. dumetorum could be useful in ingredient formulation for product development, especially as a thickening agent.

The purpose of this paper is to deal with the performance modeling and assessment of maintenance priorities for steam generation unit of a sugar plant.

The unit comprises of four subsystems, i.e., Bagasse elevator, Bagasse carrier, boiler and feed pump. The Chapman–Kolmogorov equations are generated on the basis of transition diagram and further solved recursively to obtain the performance modeling with the help of normalizing condition using the Markov approach.

Decision matrices are formed with the help of different combinations of failure and repair rates of all subsystems. The performance of steam generation unit is evaluated in terms of availability levels depicted in decision matrices and plots of failure rates and repair rates of various subsystems. The maintenance priorities of various subsystems of steam generation unit are decided on the basis of effect of failure and repair rates of subsystems on the availability of steam generation unit. The key finding is that the boiler subsystem is the most critical subsystem and hence should be kept on top maintenance priority for performance enhancement of the steam generation unit.

The acceptance of both performance modeling and maintenance priorities decision by the management of sugar plant will result in the enhancement of unit availability and reduction of maintenance cost.

OILS and greases are in many ways excellent lubricants. In fact, it is difficult to envisage modern industry without them. There are, however, a number of applications where the presence of oil or other petroleum lubricants, gives rise to serious operational problems. One of these applications is the lubrication of Steam Cylinders.

Steam turbine final assembly is a dynamic process, in which various interference events occur frequently. Currently, data transmission relies on oral presentation, while scheduling depends on the manual experience of managers. This mode has low information transmission efficiency and is difficult to timely respond to emergencies. Besides, it is difficult to consider various factors when manually adjusting the plan, which reduces assembly efficiency. The purpose of this paper is to propose a knowledge-based real-time scheduling system under cyber-physical system (CPS) environment which can improve the assembly efficiency of steam turbines.

First, an Internet of Things based CPS framework is proposed to achieve real-time monitoring of turbine assembly and improve the efficiency of information transmission. Second, a knowledge-based real-time scheduling system consisting of three modules is designed to replace manual experience for steam turbine assembly scheduling.

Experiments show that the scheduling results of the knowledge-based scheduling system outperform heuristic algorithms based on priority rules. Compared with manual scheduling, the delay time is reduced by 43.9%.

A knowledge-based real-time scheduling system under CPS environment is proposed to improve the assembly efficiency of steam turbines. This paper provides a reference paradigm for the application of the knowledge-based system and CPS in the assembly control of labor-intensive engineering-to-order products.