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Rock Street, San Francisco

Throughout history cities have been hotspots for the generation of jobs and employment; as these cities grow any unused (or poorly used) space is converted to offices, shops, and other such workplaces. Consequently, it could be said that there is a greater number of jobs in a given area. Each job needs a worker, and each worker a home, but as this job density increases the workers must seek residence further and further away from the cities. How then must these people get to work each day whilst living so far away from their place of employment? Cars produce a great deal of congestion within the city centre, buses get caught in the midst of this congestion and cycling can only take one so far and buses. People, then, often look to trains to make their morning commute.Failing to make an important meeting, missing that all important morning coffee, having less time to complete a vital task. All are consequences of being late. It is important, then, that there is both reliability and efficiency when it comes to travelling to work, yet when one thinks of the National Rail service these descriptions tend not to come to mind. In this essay, I will explore not only the development of the modern locomotive but also how we can take inspiration from the train networks in other countries (such as Japan) to strive for that greater efficiency and reliability that we are presently lacking. It is important to consider the development of the train as in analysing its evolution we can try to understand why certain designs choices were made with consideration to past focus points for the designs such as performance, safety, comfort. In learning how the engineers of past took this focus and adapted their systems and also have regard to how present frameworks have been constructed we can aim to improve. This is especially relevant for trains now as in England both HS2 and CrossRail are beginning to be implemented. The latter of these is already starting to expand it’s network and will continue to do so over the coming few years. It is essential, therefore, that we learn from past and present issues before they manifest in our future innovations.The history and development of trains as we know them today spans over 200 years, but it is worth noting that the first implementation of train-like designs stretches back to ancient civilizations in Greece and Egypt wherein tracks were laid down that allowed for horses to pull small carriages of freight (iron, coal etc) in two directions. Of course, for there to be great innovational leaps there must be invented a driving force that came not from an animal, but from machinery. Therefore to discuss the evolution of the train, we must first consider the progression of its original source of power. The steam engine. Their basic principle is to take a fluid (namely water) and to use the gases generated from boiling it to expand through pistons in order to output useful mechanical work. The transition to the steam engine that was used in the early locomotives was heavily pioneered by James Watt who, in 1781, patented a steam-powered engine that incorporated rotary motion. A key aspect of this design was the use of steam at a pressure that was greater than atmospheric and so the drive of the piston was aided by a generated partial vacuum. This particular engine outputted approximately 5 horsepower. In contrast, modern trains can achieve a power output in excess of 20,000 horsepower. It is Richard Trevithick that we owe thanks to also, as it was he who invented a high-pressure steam engine small enough to be used to power vehicles, and several years after this it was also Trevithick that made the first steam locomotive at Samuel Homfray’s Penydaren Ironworks in South Wales. And “On February 21, 1804 it was this locomotive that won a wager for Homfray by hauling a load of 10 tons of iron and 70 men along 10 miles of tramway.” Over the several years that followed on from this there were several further iterations of this locomotive. Over the following ~40 years progress was somewhat slow, but one key design change was that of the orientation of the piston axis, in making this horizontal (as opposed to the previous vertical arrangement) the engines could begin to be more compact and so more powerful engines were able to be contained in smaller areas. A design that proved this was a valid design choice was the Corliss steam engine that (in 1849) was patented as a 4 valve engine that used 30% less steam. For this design, Corliss received the Rumford medal, the committee for which stated that “no one invention since Watt’s time has so enhanced the efficiency of the steam engine”. Following from the development of the locomotives, longer railway lines across Europe and America began to be constructed as early as the 1810’s. Over the subsequent ~70 years, the steam locomotives got more efficient (with respect to energy output), cities and countries became more connected and thus the second industrial revolution (the technological revolution) commenced. One key limitation for early trains was that the engines could not be too large as they became far too heavy for the relatively brittle cast iron railways. As such, not only was the performance of the locomotives limited, but the trains themselves could not be too long as once again this was far too much weight for the rails to manage. This all changed, however when steel production boomed in the 1860’s. The great increase in steel availability meant that the cost to use steel for the rail network was significantly reduced and so over time the pre-existing networks were upgraded and larger and longer networks began to be laid. With more fortified railroads in place, the trains could become longer and so would need to be more powerful. Concurrently, development of the internal combustion engine (ICE) was taking place an in 1876 Nikolaus Otto had created the first internal combustion engine as we know it in modern times. It took a further 18 years before the first ICE locomotive had been created, this particular engine used kerosene as its fuel source. After a series of these trains was produced until 1903 (Primarily for use by the British Military) it was found that other oil fractions would be more suitable. Petrol-mechanical locomotives were produced not long after this wherein a petrol-fuelled internal combustion engine directly powered the wheels via a transmission by a series of mechanical linkages. Similarly, diesel-mechanical locomotives came into production and use at around the same time (~1906-1912). This particular transmission configuration generally outputs a relatively low power and consequently has a low speed. Whilst the development of such locomotives was necessary with respect to the development of the modern train; its usage has declined significantly. Today, diesel-mechanical trains are for the most part confined to act as switching locomotives that are used to assemble and disassemble trains from the locomotives and the carriages to the entire train itself. Moreover, it is important to note that a key issue of diesel-mechanicals is the complexity of the transmission as it is not only very large relative to the size of the engine itself, but also has many stages that can make it very expensive to manufacture. The next progression from this system is to the diesel-electric engine-transmission system. The process by which this operates is that a diesel internal combustion engine outputs to either a DC generator or an AC rectifying alternator. These electrical systems in turn directly power electric motors which drive the wheels. Therefore there is no direct mechanical link between the engine and the wheels. Diesel-Electric trains are to this day still very much in use, but are slowly being phased out in favour of their more sustainable, fully electric counterparts. Thus, it is now time to analyse the present day systems in place and to then look to the future to forecast where this vital industry may head.It is evident that the history of the locomotive is extensive, but with the information age now upon us and electrification an inevitability, trains will soon no longer require a locomotive to power them. For the most part, modern trains are variants of EMU’s (Electric Multiple Unit) this means that the train no longer requires a singular locomotive car to effectively ‘drag’ the rest of the train carriages. Initially, it may seem as though there could be extra room for passengers now that there is no engine and therefore no fuel has to be carried. However for an EMU to operate there are several functions that must be performed by the composite cars (carriages are often able to perform more than one of the listed functions) to drive the train, these are power, motor, and driving. The power aspect refers to the ability for the train to be able to acquire the current from the external source. This electricity may be delivered by either an electrified third rail upon which the train travels or a set of overhead electrified power cables. The former of which requires ‘pickup shoes’ that glide over the third rail and collects the current whilst the latter requires pantographs that are composed of a metal framework and a low-friction contact strip between the frame and the power cables. Transformers are also necessary so that the input voltage can be converted to one more suitable for the traction motors which conveniently takes us onto the next aspect required for the EMU system. The motors. The primary traction motors are mounted on the same car as the power systems. This design choice has been made as it showed in testing that it provided better dynamics allowing for improved high-speed operation. Lastly, the aforementioned driving element is simply a driving cab wherein the driver of the train sits and controls the train. Trivially, there is a driving cab located at either end of the train such that it can operate in either direction on a railway so it does not have to turn around at its point of termination. Whilst subjective, it can most certainly be argued that Japan is at the forefront of efficiency (with regards to timing) and the developing and implementing new concepts for trains. It is essential then, that their success in modern history is analysed as it is likely that the technology that is presently in its infancy in Japan will move to the mass consumer market over the next 25 years. Before looking to the future we should first evaluate the present day accreditations that are associated with the Japanese rail service. First and foremost is the punctuality. For the Shinkansen train line (often called the Bullet Train) in the fiscal year of 2012/2013, the mean time by which the train was delayed over that entire year was merely 36 seconds. This statistic alone is a rather incredible feat, even more so when this time also takes into consideration delays caused by natural disasters and other unforeseen circumstances. How is this possible? The minimising of any delays falls heavily down to the sheer amount of training a driver of the bullet train must undergo. To be able to drive the train unassisted, a driver must have been in a station staff role for at least 2 years, a further 2 years as a conductor and then another several years as a driver on a slower train line (Zairaisen trains) before finally taking part in rigorous simulations. After this great length of time in the rail service, the drivers are able to calculate exactly how fast they must accelerate and decelerate in and out of stations as well as work out how fast they must go if they are to spend too long or not long enough at a station. This requirement may seem slightly extreme, but given the punctuality mentioned before and the fact that there have been no fatalities due to a Bullet Train crash since operations began, it is hard to argue with it. What, then, is the next step forward? Surely there cant be a significant improvement on these figures? In my opinion, it is not the improvement of the stats that is important. But the decrease in the training required by the drivers. By which I suggest the notion of having no drivers. Autonomy is still in its early stages. It is highly unlikely that we will see driverless cars in the next few years, and even more unlikely that we will see autonomous trains in the next 25 years. Despite this, there have been great leaps in autonomy in cars within the past few years. Most notably would be in the Tesla vehicles that have been released/announced. With three cars having already been brought out (Model X, Model S and Model 3) and two further cars in the works (Roadster and Semi-Truck) all having Tesla’s latest driverless software, this seemingly distant concept is slowly becoming reality. Other large companies (Google and Apple) have invested into this industry also, so it is not that great of a conceptual jump to make that this is where the car market may head in the near future. Provided, of course, that these ventures prove successful and safe, it is very probable that other modes of transport could well become automated, namely the train. Initially, it would be expected that drivers would still be present to ensure a certain level of contingency within the system. But over time it is very plausible that trains (not just on this Shinkansen line) could adopt a fully autonomous driving operation wherein the arrivals and departures of all trains could be controlled from a centralised location. A key question for this concept is simple…why? It is common knowledge that train prices are extortionate, while this is of course in part due to the rail networks ultimately being a business that must generate profit, the running cost per mile will take into consideration the wages of the driver. So to eliminate the need for a driver would likely bring the cost of rail travel down. Understandably, this intricate of a software would cost greatly in research and development, but once this initial price has been displaced the travel costs would surely come down. What next then for trains? Punctuality, safety, sustainability, comfort. These qualities are what one would associate with a train of the future. Yet there is one quality that is not listed here, one that humans as a species have always been fascinated with, be it for a primal reason or for convenience. Speed. Presently, China holds the record for the fastest trains that are operational as a public rail line “at 350 km/h, China’s new Fuxing trains have become the world’s fastest bullet trains”. This great speed has in fact already been beaten by Japan (unsurprisingly) who have achieved a top speed of over 600km/h! This particular train is still in its testing phase and will not be open to the public for several years. To achieve this remarkable feat Japan had to ditch conventional rail travel in favour of a more experimental and innovational approach. These particular trains make use of magnetic levitation (Mag-Lev) whereby once at a high speed the train’s wheels retract (not dissimilar from an aircraft) and then levitates ~0.1m above the tracks as it is then propelled by the repulsion between the rails (which would have to be a permanent magnet) and a superconducting magnet placed on the underside of the train. In doing this there is zero frictional forces between the train and the rails and can, therefore, attain much greater speeds. The key issue that is being faced with the development of mag-lev train lines is that of the superconductor. The technology in this field has not yet developed enough to allow for superconductors to operate at ambient temperatures. Instead, the ceramics used must be cooled with liquid nitrogen in order for them to reach this superconducting state. It is not doubted that mag-lev trains will be in operation in the near future, but until superconductors are developed enough such that they can operate closer to atmospheric temperatures it is likely that travel on these high-speed lines will initially be very expensive. To return to the points mentioned at the start, it is evident that our modern trains have developed significantly over the course of its 200+ year history and that from the early generations of the steam-powered locomotive to the all-electric trains of today, sustainability and efficiency have been revolutionised. The initial development of the steam engine also marked the early stages of the industrial revolution and it is clear to see why. Trains can connect people and industry in a way that no other forms of transport are really capable of. On large scale, Trans-continental rail lines allowed the passage from the east to the west of the United States to be a matter of hours rather than days or weeks and on a smaller scale, it has connected cities by means of the underground networks that formed as a subset of the train technology in place overground. Would cities as we know them today function in the same way without the link from one corner to another? This mode of transport is most certainly pivotal within the role of a city and as cities grow larger, they must remain connected.

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