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With the popularization of permanent magnet linear synchronous machines (PMLSMs) in recent years, the temperature rise has attracted increasingly attention since excessive heat generated in the windings could deteriorate the electromagnetic performance. In order to solve this problem, adopting water-cooled system is an effective method. The purpose of this paper is to investigate a 12-slot/11-pole (12S/11P) water-cooled double-sided PMLSM, which adopts the all teeth wound concentrated winding and shifted armature ends.

Based on 2D finite element analysis (FEA), the thermal performances, such as temperature distribution, the optimization of water flow rate and the influence of demagnetization, are investigated under the condition of continuous duty. Then the maximum current density and average thrust force are calculated for PMLSMs with or without water-cooled system. Finally, the detailed comparison is made between single-sided PMLSM and double-sided PMLSM.

With water-cooled system, the thermal performance of PMLSM can be improved, such as an efficient decrease of temperature rise, restriction of permanent magnet demagnetization and a dramatic increase of the maximum thrust force. It is found that the water flow rate has a significant impact on temperature rise, which can be optimized according to demands.

Electromagnetic and thermal coupled analysis is proposed in this paper. It can approximately predict thermal performance and save the manual iteration time at the same time. This method also can provide as a reference of thermal analysis for other PMLSMs.

The coolant systems of pressurised, water‐cooled, nuclear reactors become radioactively contaminated. Since reactors, like other process equipment, require personnel for operation and maintenance, this coolant system contamination and associated radiation may pose difficult operating problems. Inefficiencies in personnel utilisation result as the radiation levels increase. Generally the radiation levels tend to increase with time. Decontamination is then required to lower radiation levels and to improve personnel utilisation. During a reactor's lifetime, the coolant systems may be decontaminated a number of times to keep radiation levels within acceptable limits. Since this decontamination operation involves chemical cleaning of the reactors' coolant system it has a certain corrosive effect upon the components of the system. To determine these corrosive characteristics, a procedure simulating the cyclic filming and defilming in the pressurised water system is employed in the USA. Special equipment is needed to simulate reactor conditions and to allow evaluation of decontamination methods. Although this article is focused on nuclear reactor systems, the technique of cyclic filming and defilming could be used readily to determine long‐term corrosion effects in other industrial systems where chemical cleaning is frequently employed, such as in boilers, heat exchangers, evaporators, reactors, condensers, and process vessels. Equipment designs and operating procedures would be formulated so as to simulate process and chemical cleaning conditions for the particular system of interest.

ALL historical records of aviation, from the earliest attempts at flight to our present‐day Schneider Trophy and other record flights, show that in common with those nineteenth‐century experimenters our modern engine and aircraft designers are in one continuous struggle with the physical laws of weight. It is true that the early pioneers were faced with the problem of flying as such to the extent of carrying one man by a heavier‐than‐air machine a few hundred yards, but once this was achieved development quickly enlarged the problem, and weight, with its relationship to power, lifting surface, safety factors, performance, range, and later—with the coming of civil transport—financial weight in the form of pay load, have become the all‐important item with the aeronautical engineer and constructor.

This was selected as an excellent example of one of the papers published in the first ever issue of Aircraft Engineering in March 1929. It was presented at the Royal Aeronautical Society on 22 November 1928 and then published in the journal. It discusses the characteristics and influences affecting aircraft weight, and possible developments with increasing size and therefore provides a fascinating reminder of technology and thinking in the late 1920s.

Design teams have difficulties in assessing building carbon emissions at an early stage, as most building energy simulation tools require a detailed input of building design for estimation. The purpose of this paper is to develop a user-friendly regression model to estimate carbon emissions of the preliminary design of office buildings in the subtropics by way of example. Five sets of building design parameters, including building configuration, building envelope, design space conditions, building system configuration and occupant behaviour, are considered in this study.

Both EnergyPlus and Monte Carlo simulation were used to predict carbon emissions for different combinations of the design parameters. A total of 100,000 simulations were conducted to ensure a full range of simulation results. Based on the simulation results, a regression model was developed to estimate carbon emissions of office buildings based on preliminary design information.

The results show that occupant density, annual mean occupancy rate, equipment load, lighting load and chiller coefficient of performance are the top five influential parameters affecting building carbon emissions under the subtropics. Besides, the design parameters of ten office buildings were input into this user-friendly regression model for validation. The results show that the ranking of its simulated carbon emissions for these ten buildings is consistent with the original carbon emissions ranking.

With the use of this developed regression model, design teams can not only have a simple and quick estimation of carbon emissions based on the building design information at the conceptual stage but also explore design options by understanding the level of reduction in carbon emissions if a certain building design parameter is changed. The study also provides recommendations on building design to reduce carbon emissions of office buildings.

Limited research has been conducted to date to investigate how the change of building design affects carbon emissions in the subtropics where four distinct seasons lead to significant variations of outdoor temperature and relative humidity. Previous research also did not emphasise on the impact of high-rise office building designs (e.g. small building footprint, high window-to-wall ratio) on carbon emissions. This paper adds value by identifying the influential parameters affecting carbon emissions for a high-rise office building design and allows a handy estimate of building carbon emissions under the subtropical conditions. The same approach may be used for other meteorological conditions.

The purpose of this paper is to design and implement a directly cooled photovoltaic thermal (PV/T) hybrid system.

The research design subjects, instruments and methods that were used to collect data are as detailed in the paper. Two polycrystalline photovoltaic (PV) modules were used in this study.

The directly water-cooled PV module (PV/T) was found to operate better as compared to a naturally cooled module for the first three months. The PV/T initially operated at a higher electrical efficiency for 87 per cent of the day. The monthly energy-saving efficiency of the PV/T was found to be approximately 61 per cent, while the solar utilisation of the naturally cooled PV module M1 was found to be 8.79 per cent and that of M2 was 47.93 per cent.

The major limitation was the continued drop in efficiency after the first three months of the PV/T placed outdoors. The fall in the efficiency was attributed to water ingress.

Direct water cooling of PV modules is possible, only that a better sealing is needed to prevent water ingress.

PV air cooling has been researched on. Use of water as a cooling medium has been carried out using serpentine pipes or riser tube, and no direct water cooling on the back of the module has been researched on.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

This paper aims to develop a multi-criteria decision framework (MCDF) for the selection of appropriate low carbon building (LCB) measures for office buildings in Hong Kong.

The research was carried out through a critical literature review and a case study with a low carbon office building project.

In total, 26 LCB measures were identified, under the five groups of building envelope, heating, ventilating and air conditioning system, lighting and elevators, renewable energy and appliances. Also identified were 16 decision criteria, centred on the implementation-related, economic, environmental and production-related aspects. The identified measures and criteria, coupled with the information and business processes of office building project delivery, formed the conceptual MCDF. The MCDF was also verified using an office building project.

The limitation of this research was the absence of the energy bill which could help to further verify the model in the case study.

The developed framework should add value to knowledge of the use of multi-criteria decision-making methods and support the design decision-making of selecting LCB measures for office building projects in Hong Kong. The findings should also inform LCB design in other hot and humid subtropical urban environments.

THE interest in anticipation offered by an International Aeronautical Exhibition is akin to that inspired by friendly participation in the reunion of a large and normally‐scattered family for some special celebration. One will look to see whether the elder stalwarts continue in full vigour; has that adolescent promise developed into maturity, or was it merely an evanescent brilliance; is new blood coming in, to bo assimilated in the traditions of the breed; or is the general stock slipping back, pot‐bound and sterile of fresh enterprise and foresight? In one's judgment one must be careful, however, to remember that it is a festal occasion, not the routine of life.

The purpose of this paper is to consider thermal analysis as part of an automated sizing and design process. The temperature estimation at characteristic points of the machine, and in particular in permanent magnets, is essential to accurately simulate the electromagnetic behavior and avoid irreversible demagnetization.

In this paper, an electromagnetic dimensioning model, parameterized by finite element analysis, is coupled to a thermal lumped‐parameter model to constitute a fast and efficient design tool for electrical machines.

A parameterized and hybrid FE‐analytical electromagnetic model, which combines analytical and numerical advantages, to archive a fast and accurate electromagnetic simulation results is combined with a thermal lumped‐parameter model for water‐cooled and passive air‐cooled surface mounted permanent magnet synchronous machines (PMSM).

Sizing, electromagnetic and thermal modeling aspects are integrated into an automated design process. The whole design process is demonstrated on two standard industrial servo motors for passive and active water cooling and afterwards compared with available measurements.

The proposed method allows considering thermal aspects during the iterative automated electromagnetic design process of PMSM.