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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.

This study consists of an examination of productivity growth following three major technological breakthroughs: the steam power revolution, electrification and the ICT revolution. The distinction between sectors producing and sectors using the new technology is emphasized. A major finding for all breakthroughs is that there is a long lag from the time of the original invention until a substantial increase in the rate of productivity growth can be observed. There is also strong evidence of rapid price decreases for steam engines, electricity, electric motors and ICT products. However, there is no persuasive direct evidence that the steam engine producing industry and electric machinery had particularly high productivity growth rates. For the ICT revolution the highest productivity growth rates are found in the ICT-producing industries. We suggest that one explanation could be that hedonic price indexes are not used for the steam engine and the electric motor. Still, it is likely that the rate of technological development has been much more rapid during the ICT revolution compared to any of the previous breakthroughs.

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.

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.

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.

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.

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.

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.

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.

With few cases of STEAM teaching detailed in the depth, this paper advances the understanding of STEAM teaching practices in K-12 classrooms.

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.

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.

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.

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.

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?

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.

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.

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.

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 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.

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.

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.

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.

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.

Because of the sensitivity of the condensation parameter distribution, a double fluid numerical model and a realizable k-ε-k_d turbulence model were applied in this study, and the numerical solution for the non-equilibrium condensation flow is provided.

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.

The research results can provide reference for steam turbine wetness losses evaluation and flow passage structure optimization design.

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).

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.

Regression results of the apparatus are stable, statistical significant which is verified by the statistics under design of experiment.

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.