The Anonymous Widower

A Selection Of Train Noses

I have put together a selection of pictures of train noses.

They are in order of introduction into service.

Class 43 Locomotive

The nose of a Class 43 locomotive was designed by Sir Kenneth Grange.

Various articles on the Internet, say that he thought British Rail’s original design was ugly and that he used the wind tunnel at Imperial College to produce one of the world’s most recognised train noses.

  • He tipped the lab technician a fiver for help in using the tunnel
  • Pilkington came had developed large armoured glass windows, which allowed the locomotives window for two crew.
  • He suggested that British Rail removed the buffers. Did that improve the aerodynamics, with the chisel nose shown in the pictures?

The fiver must be one of the best spent, in the history of train design.

In How Much Power Is Needed To Run A Train At 125 mph?, I did a simple calculation using these assumptions.

  • To cruise at 125 mph needs both engines running flat out producing 3,400 kW.
  • Two locomotives and eight Mark 3 carriages are a ten-car InterCity 125 train.

This means that the train needs 2.83 kWh per vehicle mile.

Class 91 Locomotive

These pictures show the nose of a Class 91 locomotive.

Note, the Class 43 locomotive for comparison and that the Driving Van Trailers have an identical body shell.

It does seem to me, that looking closely at both locomotives and the driving van trailers, that the Class 43s  look to have a smoother and more aerodynamic shape.

Class 800/801/802 Train

These pictures show the nose of a Class 800 train.

In How Much Power Is Needed To Run A Train At 125 mph?, I did a simple calculation to find out the energy consumption of a Class 801 train.

I have found this on this page on the RailUKForums web site.

A 130m Electric IEP Unit on a journey from Kings Cross to Newcastle under the conditions defined in Annex B shall consume no more than 4600kWh.

This is a Class 801 train.

  • It has five cars.
  • Kings Cross to Newcastle is 268.6 miles.
  • Most of this journey will be at 125 mph.
  • The trains have regenerative braking.
  • I don’t know how many stops are included

This gives a usage figure of 3.42 kWh per vehicle mile.

It is a surprising answer, as it could be a higher energy consumption, than that of the InterCity 125.

I should say that I don’t fully trust my calculations, but I’m fairly sure that the energy use of both an Intercity 125 and a Class 801 train are in the region of 3 kWh per vehicle mile.

Class 717 Train

Aerodynamically, the Class 700, 707 and 717 trains have the same front.

But they do seem to be rather upright!

Class 710 Train

This group of pictures show a Class 710 train.

Could these Aventra trains have been designed around improved aerodynamics?

  • They certainly have a more-raked windscreen than the Class 717 train.
  • The cab may be narrower than the major part of the train.
  • The headlights and windscreen seem to be fared into the cab, just as Colin Chapman and other car designers would have done.
  • There seems to be sculpting of the side of the nose, to promote better laminar flow around the cab. Does this cut turbulence and the energy needed to power the train?
  • Bombardier make aircraft and must have some good aerodynamicists and access to wind tunnels big enough for a large scale model of an Aventra cab.

If you get up close to the cab, as I did at Gospel Oak station, it seems to me that Bombardier have taken great care to create a cab, that is a compromise between efficient aerodynamics and good visibility for the driver.

Class 345 Train

These pictures shows the cab of a Class 345 train.

The two Aventras seem to be very similar.

Class 195 And Class 331 Trains

CAF’s Class 195 and Class 331 trains appear to have identical noses.

They seem to be more upright than the Aventras.

Class 755 Train

Class 755 trains are Stadler’s 100 mph bi-mode trains.

It is surprising how they seem to follow similar designs to Bombardier’s Aventras.

  • The recessed windscreen.
  • The large air intake at the front.

I can’t wait to get a picture of a Class 755 train alongside one of Greater Anglia’s new Class 720 trains, which are Aventras.

 

 

 

 

 

October 14, 2019 Posted by | Transport, Uncategorized | , , , , , , , , | 2 Comments

Thoughts On The Aerodynamics Of A Class 91 Locomotive

The Class 91 locomotive is unique in that it the only UK locomotive that has a pointed and a blunt end.

The Wikipedia entry has external and internal pictures of both cabs, which are both fully functional.

The speeds of the locomotive are given as follows.

  • Design – 140 mph
  • Service – 125 mph
  • Record – 161.7 mph
  • Running blunt end first – 110 mph

The aerodynamic drag of the train is determined by several factors.

  • The quality of the aerodynamic design.
  • The cross-sectional area of the train.
  • The square of the speed.
  • The power available.

The maximum speed on a level track, will probably be determined when the power available balances the aerodynamic force on the front of the train.

But with a train or an aircraft, you wouldn’t run it on the limit, but at a safe lower service speed, where all the forces were calm and smooth.

If you compare normal and blunt end first running, the following can be said.

  • The cross sectional area is the same.
  • The available power is the same.
  • Power = DragCoefficient * Speed*Speed, where the DragCoefficient is a rough scientifically-incorrect coefficient.

So I can formulate this equation.

DragCoefficientNormal * 125*125 = DragCoefficientBlunt * 110*110

Solving this equation shows that the drag coefficient running blunt end first is twenty-nine percent higher, than when running normally.

Looking at the front of a Class 91 locomotive and comparing it with its predecessor the Class 43 locomotive, it has all the subtlety of a brick.

The design is a disgrace.

Conclusion

This crude analysis shows the importance of good aerodynamic design, in all vehicles from bicycles to fifty tonne trucks.

 

If

 

 

October 11, 2019 Posted by | Transport | , | 1 Comment

Europhoenix Earmarks ‘91s’ For European Freight Use

The title of this post is the same as that of this article on Rail Magazine.

Class 91 locomotives are the locomotives at one end of an InterCity 225 train.

The picture shows three Class 91 locomotives lined up at Kings Cross station. Locomotives are normally at the Northern end of the train, with driving van trailers, which are dummy locomotives with a cab, at the other end of the train. The locomotives have a pantograph.

They are electric locomotives, with an unusual transmission, described like this in Wikipedia.

The locomotive body shells are of all-steel construction. Unusually, the motors are body mounted and drive bogie-mounted gearboxes via cardan shafts. This reduces the unsprung mass and hence track wear at high speeds. The locomotive also features an underslung transformer so that the body is relatively empty compared to contemporary electric locomotives. Much of the engineering specification for the locomotive was derived from the research and operational experience of the APT-P.

Wikipedia also says this about the locomotives.

  •  Have a power of 4.83 MW.
  • Have a weight of 81.5 tonnes.
  • Can work on 25 KVAC overhead electrification.
  • Have a service speed of 125 mph
  • Have a service speed of 110 mph going blunt end first.
  • Can operate as a  normal locomotive.

According to Wikipedia, there are a total of 31 locomotives.

They are powerful locomotives, that were designed to haul nine heavily-loaded coasches at 140 mph.

Europheonix’s Plan

Europhoenix, which is described as a railway locomotive hire company by Wikipedia, intend to do the following, according to the Rail Magazine article.

Up to twenty Class 91 locomotives will be acquired and they will be used for freight in Eastern Europe.

Two have already been purchased and these are being readied for tests.

This paragraph gives more details on the modifications and how they will be used.

EP owner Glenn Edwards told RAIL on October 4 that the locomotives would work in permanent pairs, with the blunt ends coupled together. Currently, ‘91s’ are not suitable for heavy freight haulage duty, so in partnership with Voith they will be re-geared to a lower rating to enable them to operate in this manner.

A few of my thoughts!

The Double Locomotive

British Rail gets a lot of criticism.

Some of this is justified, but on the other hand, some of their track,locomotive and carriage design has admirably stood the test of time.

In his quote, Glenn Edwards seems very confident that the engines can work in permanent pairs.

As the Class 91 locomotives were designed to work as normal locomotives, perhaps the ability to work as a pair, was part of the original specification.

But as no-one ever used them to haul heavy freight trains, the feature was never needed.

British Rail has form in using pairs of electric engines to haul freight.

 

The picture shows a pair of Class 86 locomotives, which were built in 1965-66, pulling a heavy freight train through Canonbury in 2019.

I also must show this picture of a British Rail-era Class 90 locomotive double-heading a heavy freight train with a Class 66 diesel locomotive.

Is this the ultimate bi-mode locomotive for the UK?

I’ve never seen the formation again or found any reference on the Internet.

I wouldn’t be surprised to be told, that running two Class 91 locomotives, blunt end together, was part of the original design.

The pair would be a powerful beast.

  • Almost ten MW of power.
  • Eight driven axles.

But the pair would have a lowish axle loading of around twenty tonnes.

Modifications Planned

The only modification noted in the Rail Magazine article is to change the gearing from that needed for a 140 mph passenger train to that needed for a slower freight train.

Hopefully the manufacturer of the original gear-boxes are still in existence.

Other Information

There is a discussion about these locomotives on this topic on RailUK Forums.

One post says this.

I spoke to a colleague the other day who said ROG were getting 2X91’s for testing the new wires on the MML.

ROG is Rail Operations Group and they are should be well-qualified to do the testing.

According to Wikipedia, there is a lot of space inside the locomotive, so could this space be used to house instrumentation used to test the overhead wires?

Could Pairs Of Class 91 Locomotives Be Used For Freight In The UK?

I think it all depends on the routes, the amount of electrification and the economics.

On the other hand new Stadler Class 93 locomotives might be a better alternative.

Conclusion

It does look like Eirophoenix have organised an export deal, that is to the benefit of several parties.

October 10, 2019 Posted by | Transport | , , , , | Leave a comment