måndag 25 juni 2018

Swansea Bay barrage dropped

This project sounds like one of those environmentally friendly schemes which is almost certainly just the opposite. Just a few of the doubts concern...
  • The embodied energy of the concrete structure.
  • The effect on wildlife, including fish and wading birds.
  • The long-term consequences of the scheme, eg silting and pollution.
  • Maintenance issues eg marine growth on the turbines, and silting again.
The uncompetitive cost of the electricity it would generate gives some indication of the embodied energy the scheme would absorb before any power was generated. I am inclined to think it is a good thing that the scheme has been abandoned.

onsdag 20 juni 2018

Västlänken - the chaos begins

Next week come the first major disruptions due to Västlänken. Major alterations to Gothenburg’s tram services are always a feature of the summer as the holiday season is set aside for renewal of track. That is a story in itself, because the fleet of Italian trams that came into service in 2010 are inflexible and cause additional wear on curves. However, on top of this, there are closures in preparation for Västlänken, and to crown it all, the road tunnel along the Göta Älv will be closed for six months in one direction for the same reason. That will cause horrendous and widespread delays and congestion.

It is already proving to be a project too far, and that is just a month into the construction period.

In addition, trenches are appearing all over the place, blocking the entrances to shops and restaurants, which cannot be doing their business any good at all. I wonder how many bankruptcies there will be before the wretched scheme is complete?

onsdag 6 juni 2018

Microsoft’s underwater data centre

Microsoft’s underwater data centre idea plumbs the depths in several ways. The idea is to use cold surrounding seawater to dissipate the heat generated. This is of course low-grade heat, but it is perfectly suitable for the heating of buildings, hot water systems, etc, which adds up to a huge amount of energy use worldwide, especially in the colder parts of the world.

A data centre in Helsinki uses the waste heat in this way, heating a group of adjacent buildings. I would be happy to have a data centre in our basement if it meant no more heating bills. There is a fibre optic cable in the street outside, so there is no need for an underwater cable.

What are Microsoft engineers thinking of?

fredag 18 maj 2018

Minding the gap

Gaps between platforms and trains are another problem caused when there is a mis-match between the infrastructure and the trains. When the system was built in the early days of Queen Victoria, passenger carriages were short four-wheeled vehicles, typically less than 10 metres long. Over the next century, the standard length of a British passenger vehicle had risen to 20 metres. With bogies close to the ends, and about 14 metres apart, there would be a large gap on sharply curved concave platforms. This was not usually a problem with slam-door trains as passengers would lower the window inside the door and use the top of the window frame for support when getting on and off. The trains were also fitted with external handrails. This was not an ideal arrangement but it worked.

The first large scale use of sliding door trains on the national system adopted the 1/3:2/3 configuration, as in these class 313 trains seen here at Brighton. The size of the gap is obvious. From the mid-1980s, this 1:3:2/3 configuration became standard for all trains in Britain apart from the inter-city fleet, where end doors became the standard. The final BR designs, however, adopted a 1/4:3/4 configuration, with two seating bays between the vehicle ends and the doorway vestibule.  This was a feature of the Networker and derivatives of the design including the 20 metre Electrostar classes. This reduced the size of the gap because the doorway was only just inside the bogie wheelbase. The 23 metre Turbostars were similar, but with five bays instead of four between the doorways.

The new CAF Civity trains for Northern seem to have reintroduced the problem, as these are 23 metre vehicles with the doorways three bays in from the ends, and four bays between the doorways. As the photograph shows, the doorways are well inside the bogie wheelbase, which could give rise to large gaps at concave platform faces. We shall see.

The problem could of course be solved entirely if the trains were fitted with retractable steps, but that is a step too far, it appears.

onsdag 16 maj 2018

The UK loading gauge question


One would have thought that a priority for rolling stock designers would have been to make the best use of the limited UK loading gauge. Seemingly not. The illustration of the interior of the new locomotive-hauled Nova 3 coaches for Transpennine Express is taken from an article in International Railway Journal; I hope this is acceptable under the fair use of copyright rules.

Take a look at the skirting area. This shows the problem caused by the very sharp lower bodyside curvature apparent in exterior views of the stock. This example is almost the rule. The same thing affects much of the rolling stock built since 1990, including the BR-designed Networkers and the BREL Electrostars and Turbostars. The bodyside profile makes no sense within the parameters of the UK loading gauge.

As is well known, the British loading gauge is little bigger than that permitted for narrow gauge railways such as those of Japan and South Africa. This is mostly due to the closeness of adjacent tracks and the low bridges and tunnels, but the problem is aggravated by the British practice of having high platforms, approximately 90 cm high. The issue was carefully examined when British Railways was formed in 1948, and the result was the C1 loading gauge (diagram above), which applied to passenger vehicles of a nominal width of 20 metres with bogie centres 14.17 metres apart - as close as practical to the vehicle ends. The mark 1 stock was built to comply with this standard, and more recent stock such as the Bombardier class 377 Electrostars are constructed to the same main dimensions.

Eventually, longer vehicles came into use. These were made narrower, in accordance with a geometrical formula to take account of overthrow on curves. Another important change was the use of air springing which is softer, which meant that carriages had to be narrower at the cantrail, where the sides meet the roof.

As far as the passenger space is concerned, the salient point is that the maximum width of the loading gauge is available from 1.225 metres above rail level and upwards for about 1.2 metres, when the vehicle body has to become narrower. The C1 loading gauge for 20 metre vehicles allows a full 2.82 metres, tapering to 2.62 metres at the cantrail. Logically, it generates a profile similar to that in these vehicles below.

The important factor here is the floor height. The standard height used to be 1.3 metres, which resulted in no loss in width, leaving space for skirting level ducts without cutting into legroom; this is a feature of, for instance, all the BR mark 1 stock. The Hitachi 800 series are also unaffected due to the high floor level enforced due to the size of the underfloor engines. Suburban stock, on the other hand, with a lower standard floor height, can suffer badly from reduced floor width, although it does not affect the Siemens Desiro class 450 and similar types. That said, one wonders why lower bodyside curvature is needed on suburban stock at all as the footsteps project beyond the bodysides.

The problem can be seen clearly in the top photograph; passengers sitting next to the windows will only be able to put one foot on the floor unless they twist themselves at an angle. Why, then, do these vehicles have such pronounced lower bodyside curvature, since there is no necessity for it through loading gauge constraints?

UK productivity questions

The latest UK productivity figures for the first three months of 2018 are not good, prompting the usual recriminatory comments. However, there are basic questions which rarely seem to get asked.
  • Transport costs.
  • High reject rates. 
  • Remedial work having to be done on finished products.
  • Inefficient layout of factory premises.
  • Inefficient delivery of components and sub-assemblies to workbenches.
  • Works kept waiting for components to arrive.
  • Products not designed for efficient production.
  • Excessive down-time of plant and machinery. 
  • Poor communications between management and shop-floor workers. 

It is a subject that needs to be put under the microscope if remedies are to be found. Hand-wringing achieves nothing.

torsdag 10 maj 2018

The Journey East #10

Three of us were received into the Orthodox Church today. One of us was baptised in the lake and then Chrismated - anointed with Holy Oil, on the forehead, eyelids, ears, nose, mouth, hands and feet. The others two, being Roman Catholics, were only Chrismated, having been baptised already.

Many thanks to all involved, including those who acted as Godparents and Fr Mikael Fälthammar, who has given us the course of instruction and received us into the Church.

It is one of the most important event that anyone could have in their life. The journey is of course not over. This is a staging post on the journey.

Swansea Bay barrage dropped

This project sounds like one of those environmentally friendly schemes which is almost certainly just the opposite. Just a few of the doubts...