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1 – 10 of over 7000The steam engine was the first practical means of producing mechanical power from the heat of combustion of a fuel, and its introduction was a vital factor in the progress of the…
Abstract
The steam engine was the first practical means of producing mechanical power from the heat of combustion of a fuel, and its introduction was a vital factor in the progress of the Industrial Revolution. For many years the development of the steam reciprocating engine continued apace, but in the early years of the present century introduction of the steam turbine and internal combustion engine made available alternative methods of power production. From then on interest in the steam reciprocating engine tended to slacken and, although it has shown a number of notable improvements, far more spectacular advances have been made in other power units.
Siyuan Lyu, Shijing Niu, Jing Yuan and Zehui Zhan
Preservice teacher (PST) professional development programs are crucial for cultivating high-quality STEAM teachers of the future, significantly impacting the quality of regional…
Abstract
Purpose
Preservice teacher (PST) professional development programs are crucial for cultivating high-quality STEAM teachers of the future, significantly impacting the quality of regional STEAM education. The Guangdong-Hong Kong-Macao Greater Bay Area, as a region of cross-border cooperation, integrates the resources and advantages of Guangdong, Hong Kong, and Macao, possessing rich cultural heritage and innovative capabilities. Transdisciplinary Education for Cultural Inheritance (C-STEAM) is an effective approach to promoting educational collaboration within the Greater Bay Area, facilitating the integration of both technological and humanities education. This study aims to develop a Technology-Enabled University-School-Enterprise (T-USE) collaborative education model and implement it in the Greater Bay Area, to explore its role as a support mechanism in professional development and its impact on C-STEAM PSTs' professional capital.
Design/methodology/approach
Adopting a qualitative methodology, the study interviewed PSTs who participated in a C-STEAM teacher education course under the T-USE model. Thematic coding is used to analyze their knowledge acquisition, interaction benefits with community members, and autonomous thinking and decision-making in theoretical learning and teaching practice.
Findings
The findings show that the T-USE model significantly enhanced the PSTs' human capital, including teaching beliefs, knowledge, and skills. In terms of social capital, PSTs benefited from collaboration with PST groups, university teaching teams, in-service teachers, and enterprises, though challenges such as varying levels of expertise among in-service teachers and occasional technical instability emerged. For decisional capital, the T-USE model provided opportunities for autonomous thinking and promoted teaching judgment skills through real teaching challenges and scenarios. Reflective practice activities also supported PSTs' professional growth.
Originality/value
This study reveals the effectiveness and internal mechanism of the T-USE model in C-STEAM PST training, offering significant theoretical and practical references for future PST education.
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Esmail Lakzian, Mostafa Ramezani, Sima Shabani, Fahime Salmani, Miroslaw Majkut and Heuy Dong Kim
The purpose of this study is to model steam condensing flows through steam turbine blades and find the most suitable condensation model to predict the condensation phenomenon.
Abstract
Purpose
The purpose of this study is to model steam condensing flows through steam turbine blades and find the most suitable condensation model to predict the condensation phenomenon.
Design/methodology/approach
To find the most suitable condensation model, five nucleation equations and four droplet growth equations are combined, and 20 cases are considered for modelling the wet steam flow through steam turbine blades. Finally, by the comparison between the numerical results and experiments, the most suitable case is proposed. To find out whether the proposed case is also valid for other boundary conditions and geometries, it is used to simulate wet steam flows in de Laval nozzles.
Findings
The results indicate that among all the cases, combining the Hale nucleation equation with the Gyarmathy droplet growth equation results in the smallest error in the simulation of wet steam flows through steam turbine blades. Compared with experimental data, the proposed model’s relative error for the static pressure distribution on the blade suction and pressure sides is 2.7% and 2.3%, respectively, and for the liquid droplet radius distribution it totals to 1%. This case is also reliable for simulating condensing steam flows in de Laval nozzles.
Originality/value
The selection of an appropriate condensation model plays a vital role in the simulation of wet steam flows. Considering that the results of numerical studies on condensation models in recent years have not been completely consistent with the experiments and that there are still uncertainties in this field, further studies aiming to improve condensation models are of particular importance. As condensation models play an important role in simulating the condensation phenomenon, this research can help other researchers to better understand the purpose and importance of choosing a suitable condensation model in improving the results. This study is a significant step to improve the existing condensation models and it can help other researchers to gain a revealing insight into choosing an appropriate condensation model for their simulations.
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Danielle Herro and Cassie Quigley
This paper aims to broaden the conversation regarding STEAM by investigating the new form of education. The novelty of science, technology, engineering, art and mathematics…
Abstract
Purpose
This paper aims to broaden the conversation regarding STEAM by investigating the new form of education. The novelty of science, technology, engineering, art and mathematics (STEAM) instruction in K-12 classrooms means few cases of STEAM teaching are documented in depth.
Design/methodology/approach
As part of a larger multi-year study researching STEAM teaching practices in 14 middle school classrooms in the southeastern USA, the article first summarizes prior research findings and then presents ideas for higher education and K-12 researchers to consider when incorporating STEAM teaching in pre-service education, professional development and in classrooms. Then, the authors use a second-order narrative approach to describe three cases of teachers enacting STEAM practices in classrooms.
Findings
Drawing on the notion of “remixing” education in the context of STEAM, the authors show how each teacher alters existing practices, instead of offering entirely new instruction, as they implement STEAM teaching.
Originality/value
With few cases of STEAM teaching detailed in the depth, this paper advances the understanding of STEAM teaching practices in K-12 classrooms.
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M. Jariyaboon, P. Møller and R. Ambat
The purpose of this paper is to understand the effect of pressurized steam on surface changes, structures of intermetallic particles and corrosion behavior of AA1050 aluminium.
Abstract
Purpose
The purpose of this paper is to understand the effect of pressurized steam on surface changes, structures of intermetallic particles and corrosion behavior of AA1050 aluminium.
Design/methodology/approach
Industrially pure aluminium (AA1050, 99.5 per cent) surfaces were exposed to pressurized steam produced from a commercial pressure cooker at the maximum temperature of 116oC for 10 min. Surface morphology was observed using SEM‐EDX and FIB‐SEM. Phase identification and compositional depth profiling were investigated using XRD and GDOES, respectively. Potentiodynamic polarization measurements were used to study corrosion behavior.
Findings
A 590 nm boehmite oxide layer was generated on AA1050 associated with partially dissolved and/or fallen off Fe‐containing intermetallic particles after exposure to pressurized steam. A significant reduction (25 times) in anodic and cathodic reactivities was observed due to the formation of the compact oxide layer.
Originality/value
This paper reveals a detailed investigation of how pressurized steam can affect the corrosion behaviour of AA1050 aluminium and the structure of Fe‐containing intermetallic particles.
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Marja G. Bertrand and Immaculate K. Namukasa
Certain researchers have expressed concerns about inequitable discipline representations in an integrated STEM/STEAM (science, technology, engineering, arts and mathematics) unit…
Abstract
Purpose
Certain researchers have expressed concerns about inequitable discipline representations in an integrated STEM/STEAM (science, technology, engineering, arts and mathematics) unit that may limit what students gain in terms of depth of knowledge and understanding. To address this concern, the authors investigate the stages of integrated teaching units to explore the ways in which STEAM programs can provide students with a deeper learning experience in mathematics. This paper addresses the following question: what learning stages promote a deeper understanding and more meaningful learning experience of mathematics in the context of STEAM education?
Design/methodology/approach
The authors carried out a qualitative case study and collected the following data: interviews, lesson observations and analyses of curriculum documents. The authors took a sample of four different STEAM programs in Ontario, Canada: two at nonprofit organizations and two at in-school research sites.
Findings
The findings contribute to a curriculum and instructional model which ensures that mathematics curriculum expectations are more explicit and targeted, in both the learning expectations and assessment criteria, and essential to the STEAM learning tasks. The findings have implications for planning and teaching STEAM programs.
Originality/value
The authors derived four stages of the STEAM Maker unit or lesson from the analysis of data collected from the four sites, which the authors present in this paper. These four stages offer a model for a more robust integrated curriculum focusing on a deeper understanding of mathematics curriculum content.
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The most efficient method of lubricating the cylinders of steam engines is to employ an atomizer in the steam flow, situated a little distance before it enters the steam…
Abstract
The most efficient method of lubricating the cylinders of steam engines is to employ an atomizer in the steam flow, situated a little distance before it enters the steam cylinders, and thus inject the oil in the form of a spray so that the steam carries it to the cylinder walls and valves. In other words, the steam is made to act as a lubricant. In this way there should be no part that comes into contact with oil that is unlubricated and, furthermore, this is not only the most efficient method of lubricating a steam engine, it is also the most economical, since only small quantities are required of the finely atomized oil. It is possible to lubricate a number of pumps or several high and low pressure steam cylinders from a single feed lubricator in this way.
The objective of this paper is to analyse the evolution of international steam coal trade, the nature of coal trade contracts and the pricing mechanism in the two main coal…
Abstract
Purpose
The objective of this paper is to analyse the evolution of international steam coal trade, the nature of coal trade contracts and the pricing mechanism in the two main coal trading regions – the Atlantic and the Asia‐Pacific, from the early 1980s to recent years. The historical developments and future directions of the market are discussed.
Design/methodology/approach
The past developments of the international steam coal market is first reviewed and then compared to the four stages in the development of the international crude oil market in terms of trade and pricing, as identified in Roeber.
Findings
The four stages in the development of a mature spot market are: appearance of the need for short‐term physical balancing, availability of price reporting and transparency, price feedback from short‐term prices to long‐term prices and emergence of risk management instruments. It is found that the international steam coal market has already gone through the first three stages and is progressing in stage four. A mature spot market for steam coal is in prospect.
Originality/value
This paper provides a structured review of the development of the international steam coal market. It provides industry information to policymakers, academics and modellers who need a comprehensive understanding of the international steam coal market.
Xu Han, Zhonghe Han, Wei Zeng, Peng Li and Jiangbo Qian
The purpose of this paper is to study the condensation flow of wet steam in the last stage of a steam turbine and to obtain the distribution of condensation parameters such as…
Abstract
Purpose
The purpose of this paper is to study the condensation flow of wet steam in the last stage of a steam turbine and to obtain the distribution of condensation parameters such as nucleation rate, Mach number and wetness.
Design/methodology/approach
Because of the sensitivity of the condensation parameter distribution, a double fluid numerical model and a realizable k-ε-kd turbulence model were applied in this study, and the numerical solution for the non-equilibrium condensation flow is provided.
Findings
The simulation results are consistent with the experimental results of the Bakhtar test. The calculation results indicate that the degree of departure from saturation has a significant impact on the wet steam transonic condensation flow. When the inlet steam deviates from the saturation state, shock wave interference and vortex mixing also have a great influence on the distribution of water droplets.
Originality/value
The research results can provide reference for steam turbine wetness losses evaluation and flow passage structure optimization design.
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Shuaitong Liang, Xue Mei Ding, Xiong Ying Wu, Fan Wu and Tesfaye Mulu Asmamaw
Smooth appearance of fabrics after ironing with steam, soleplate, ironing speed and their interactions cannot be studied using household ironing machines such as hang steamer and…
Abstract
Purpose
Smooth appearance of fabrics after ironing with steam, soleplate, ironing speed and their interactions cannot be studied using household ironing machines such as hang steamer and flatiron. The purpose of this paper is to present the design and verification of a simple, low-cost test platform based on the fabric materials hang-ironing factors includes temperature, humidity, ironing speed (time).
Design/methodology/approach
This platform achieves adjustable and stable steam flow rate, enabling any ironing speed and any temperature of soleplate below 200°C. Moreover, the whole ironing process is automatically after experiment level set ahead for better observation to the ironing process.
Findings
Regression results of the apparatus are stable, statistical significant which is verified by the statistics under design of experiment.
Originality/value
It is useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research. It is also useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research.
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