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“WHAT is its top speed?” This is the question which is perhaps most frequently asked about any new aeroplane, and it is certainly a question which is usually incorrectly answered. By this is not meant the natural tendency of manufacturers to be optimistic as to the paces of their latest progeny, but merely that the top speed of an aeroplane cannot be stated with accuracy until a number of careful and methodical measurements have been made. In this article a short account will be given of the errors inherent in the ordinary methods for indicating speeds, and descriptions of some of the methods evolved to measure speed—not only top speed but speed generally—to a high degree of accuracy.

The purpose of this paper is to investigate the use of steam in order to replace air in the production of spun-like textured yarns. Further, this paper analyse the effect of production speed on process and textured yarn properties.

An existing air-jet texturing machine was modified to supply either air or steam to the texturing nozzle. Using standard commercial nozzles, both air-jet and steam-jet textured yarns were manufactured by varying production speed.

It can be concluded that steam can be used as an alternative fluid for air in making spun-like textured yarns. Results show that yarn parameters for steam-jet texturing show a similar trend to those of air-jet texturing relative to the production speed. Further, sewing threads made from steam-jet textured yarns showed good sewability up to the speeds of 350 m/min.

Only the effect of production speed on process and yarn parameters is discussed in this paper. Production speed was limited to 350 m/min due to machine constraints.

Steam is more economical than air to manufacture spun-like textured yarn at commercial pressures such as 8 bar. Steam-jet textured yarns could be used for commercial applications such as sewing threads at competitive speeds. Further, steam could be generated using sustainable and renewable fuel sources such as biomass.

This research introduced steam as an alternative fluid for air in manufacturing spun-like textured yarns.

The electromagnetic field and cooling system of a high power switched reluctance motor (SRM) are studied numerically. The geometry of the motor and its main components are established using a computer-aided design software in the actual size. This study aims to evaluate the resulting thermal losses using the electromagnetic analysis of the motor.

In the electromagnetic analysis, the Joule’s loss in the copper wires of the coil windings and the iron losses (the eddy currents loss and the hysteresis loss) are considered. The flow and heat transfer model for the thermal analysis of the motor including the conduction in solid parts and convection in the fluid part is introduced. The magnetic losses are imported into the thermal analysis model in the form of internal heat generation in motor components. Several cooling system approaches were introduced, such as natural convection cooling, natural convection cooling with various types of fins over the motor casing, forced conviction air-cooled cooling system using a mounted fan, casing surface with and without heat sinks, liquid-cooled cooling system using the water in a channel shell and a hybrid air-cooled and liquid-cooled cooling system.

The results of the electromagnetics analysis show that the low rotational speed of the motor induces higher currents in coil windings, which in turn, it causes higher copper losses in SRM coil windings. For higher rotational speed of SRM, the core loss is higher than the copper loss is in SRM due to the higher frequency. An air-cooled cooling system is used for cooling of SRM. The results reveal when the rotational speed is at 4,000 rpm, the coil loss would be at the maximum value. Therefore, the coil temperature is about 197.9°C, which is higher than the tolerated standard temperature insulation material. Hence, the air-cooled system cannot reduce the temperature to the safe temperature limitation of the motor and guarantee the safe operation of SRM. Thus, a hybrid system of both air-cooled and liquid-cooled cooling system with mounting fins at the outer surface of the casing is proposed. The hybrid system with the liquid flow of Re = 1,500 provides a cooling power capable of safe operation of the motor at 117.2°C, which is adequate for standard insulation material grade E.

The electromagnetic field and cooling system of a high power SRM in the presence of a mounted fan at the rear of the motor are analyzed. The thermal analysis is performed for both of the air-cooled and liquid-cooled cooling systems to meet the cooling demands of the motor for the first time.

The aim of the present study is to investigate the effect of fabric weave structure on air permeability and its relation with the garment ventilation.

For this purpose, five groups of cotton/polyester shirting fabrics with plain, T2/1, T2/2, T3/1 and T3/3 weave structures were studied. In order to evaluate ventilation, the garment samples were prepared in different sizes, so that the thickness of the air gap formed between the garment and the body simulator varies by zero, 1.5, 1.2 and 2.9 cm. The effect of wind and its speed (1, 2 and 3 m/s) on clothing ventilation has also been evaluated.

The results indicated that the rise of wind speed and air gap thickness, due to the increased convective heat transfer, would diminish the air gap temperature of clothing and improves its ventilation. In addition, the fabric weave pattern influences the air ability to pass through the fabric, thus affecting the ventilation capability of the garment.

Garments made of fabrics with higher structural firmness, such as the plain, not only have lower air permeability, but also has weaker ventilation capability.

THE trend of design in the modern aeroplane has been toward improved performance realised through external cleanness. It is apparent that the number of essential units comprising a modern aeroplane is nearly a minimum at the present stage of the art, and it appears also that the possibilities of further striking reductions in the drag of these units, due to change in form or shape either individually or in combination, are not great.

This chapter reviews three main issues in the interactions between air transport and high-speed rail (HSR) in China, namely the interaction between low-cost carriers (LCCs) and HSR, HSR speed effect on airlines, and airline–HSR integration. Studies on these three aspects of airline–HSR interactions have yet been well reviewed, and our chapter aims to fill in this gap. In this chapter, we comprehensively survey literature on the topics, especially studies on Chinese markets that have recently witnessed major HSR developments (and have planned further large-scale HSR expansion in the coming years). Our review shows that, first, compared to full-service carriers, LCCs face fiercer competition from HSR. However, the expansion of HSR network in China can be better coordinated with LCC development. Second, HSR speed exerts two countervailing effects on airline demand and price (the “travel-time” effect and “safety” effect, respectively). Specifically, an HSR speed reduction can have a positive effect on airlines due to longer HSR travel time, but a negative effect on airlines due to improved perception on HSR safety. Third, airline–HSR integration can be implemented through cooperation between airlines and HSR operators and through co-location of airports and HSR stations and can have important implications for intermodal transport and social welfare.

IN the earliest stages of the development of the aeroplane the speed range obtainable was small, flight occurred only at fairly high lift coefficients, and induced drag was the predominant component of total resistance, hence successful flight depended on the achievement rather of minimum weight, minimum wing loading and maximum engine power than on the achievement of minimum possible parasite resistance.

In this chapter, we will review the history, deregulation, policy reforms, and airline consolidations and mergers of the Chinese airline industry. The measurement of airline competition in China’s domestic market will also be discussed. Although air deregulation is still ongoing, the Chinese airline industry has become a market-driven business subject to some mild regulations. Then, we will review the impressive development of the high-speed rail (HSR) network in China and its effects on the domestic civil aviation market. In general, previous studies have found that the introduction of HSR services has a significant negative impact on airfare and air travel demand in China. The rapidly expanding network of HSR has important policy implications for Chinese airlines.

As a new type of spinning machine, the jet spinning machine absorbs the carding system of the rotating cup spinning series and the nozzle part of the jet spinning. This paper aims to intends to introduce the double carding structure currently studied by the rotating cup spinning into the jet spinning machine, and analyze the influence of the nozzle characteristic number on the flow field in the double carding structure to verify the advantages of the double carding structure.

The simulation is used to evaluate the performance of single/double split jet spinning and nozzle feature number, verify the technical advantages of double split jet spinning and evaluate the influence of nozzle feature number on flow field. The influence of the nozzle characteristic number on the flow pattern in the four models is compared. The advantages and disadvantages of a conventional single comb and a double comb with a bypass channel on the longer side of the transport channel as an additional air supply channel are also evaluated.

At present, the double comb technology of rotary cup spinning is being studied at home and abroad to improve the spinning quality and improve the difficult problem of mixed yarn with large difference in processing fiber properties. At present, the jet spinning machine combines the advantages of rotary cup spinning and jet spinning, absorbing the comb system of rotary cup spinning series and the nozzle part of jet spinning. Therefore, it is found that the introduction of the double-split structure into the wool jet spinning has research value to improve the spinning quality.

The purpose of this paper is to refer to the previous research on the double comb structure in rotary spinning, and to apply the double comb structure in the new jet spinning machine to improve the spinning quality. The simulation is used to evaluate the performance of single/double split jet spinning and nozzle feature number, verify the technical advantages of double split jet spinning and evaluate the influence of nozzle feature number on flow field.

The main objectives of this research work were to investigate the effect of production speed on intermingled yarn properties and melange fabric properties with special reference to melange appearance.

Polyester/nylon intermingled yarns were produced using an SSM DP3-C air-intermingling machine using commercial process parameters and Heberlein P212 nozzle. Melange fabric samples were knitted from polyester/nylon intermingled yarns while maintaining the same parameters to avoid knitting variations. The fabric samples were dyed using a sample dyeing machine while maintaining dye recipe and dyeing parameters constant to avoid dyeing variations.

The production speed has significant effect on intermingled yarn and melange fabric properties. When the production speed is increased, mingle points, mingle stability, linear density, strength and the elongation of the intermingled yarns decreases. When the production speed is increased, fabric weight decreases and the melange effect varies from dot-like appearance to line-like appearance.

Only the effect of production speed on intermingled yarn and melange fabric properties is discussed in this paper. Appearance evaluating systems developed in this research are limited to melange fabrics produced using air-intermingled yarns with two colour components.

Results indicate that the intermingled yarns for the application of melange fabrics should be developed with optimum intermingling speeds, and it should not be changed during the production since production speed has significant effect on yarn and fabric parameters. Therefore, melange appearance and fabric weight may vary between fabric lots with different production speeds even though all the other parameters are kept constant. Further, melange appearance evaluation method developed in this research could be used as a guide in developing melange fabrics.

This research introduced a qualitative and a quantitative method to analyse melange fabric appearance. This melange appearance evaluation method can be used as a guide to achieve specific melange effect in the sample development stage. Further, when a melange sample appearance catalogue is developed for all the variables for a particular fabric type using this evaluation method, customer requested appearance can be achieved in minimum sample trials which save time, capacity, money and customer credibility.