considering that micro turbines are now rather reliable always wondered about the possibility of one of these being used as a power source in a hybrid vehicle, eg like toyota prius but using a turbine?
just think, it would probably qualify for exemption from congeston charging, and if you get a tailgater...... reheat on!
;-)
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'JET 1' was on display at the Transport Extravaganza held at Wroughton Science Park, nr. Swindon, last summer. Unfortunately it was only a static exhibit!
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One of the engines was in the Engine Lab at Coventry polytechnic (or university!) when I was there.
I think the lack of engine flexibility was a problem, but it was suitable for use in the Greyhound buses which drive across the US at a constant speed for hours at a time. I think they would take most fuels too.
My Powertrain lecturer (Mr Perry) would be proud to see I remembered that!
Gareth
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Guys,
You're mising the point about the exhaust.... The 'jet' engine (actually it's technially a gas turbine engine) is used to drive the wheels via a gearbox, same as on a turbo-prop plane. This means the exhaust is not any hotter / larger volume than a normal engine burning the same amount of fuel.
IIRC some of the Navy's ships (aircraft carriers?) are powered by Rolls Royce RB-211 G-T engines.
I seem to remember also that there was a G-T engined car in F1 some time ago, but the FIA pushed it out by stangulating the size of the air intake because it was so much faster than anything else. I'll see if I can find anything relevant later on.
Richard
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"You're mising the point is used to drive the wheels via a gearbox
Not if the GT is driving an electrical generator which is used, probably via some sort of storage device, to drive the wheels electrically. Therefore no throttle lag.
As for the exhaust temp can't alter laws of physics/thermodynamics true, I'll just say CCGT to you.
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Flat in Fifth
CCGT?
That would be on hell of a car - Gas Turbine, heat recovery, steam turbine, water resevoir, condensor, some form of battery to store and smooth power flow, and a gas/oil storage tank. plus electronics to stop the GT running away with itself.
I'm not sure how many people would want to drive this behmoth into London!
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Electro man, well it is Friday!! ;-)
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That would be on hell of a car - Gas Turbine, heat recovery, steam turbine, water resevoir, condensor, some form of battery to store and smooth power flow, and a gas/oil storage tank. plus electronics to stop the GT running away with itself. I'm not sure how many people would want to drive this behmoth into London!
Funny you should say that. When I was at uni in research in Mech Eng I remember one euro project was to create the powerplant for a gas turbine electric car. It seemed like a perfectly sensible way to go. Remember that a gas turbine is not the same as a steam turbine - so no water, condensor etc.
The idea is to have electric motors for drive.
As I recall it no gearbox was required.
The gas turbine was about 18inches long and used turbo charger technology. It was about 3inches in dia. and spun at up to 100,000 rpm.
That was the problem. Hooking an alternator onto this meant that the alternator did'nt last long. So that's where the problem lay. They didn't reallywant to gear down from that speed either due to losses, bearing heat etc. I think there was a magnetic coupling from turbine to vacuum sealed alternator.
The incredible thing was that this small unit was all that was needed for main power, and it could be modified to run off just about any oil.
The idea is that car would use batteries around town but that the gas turbine cuts in on motorways or for charging batteries.
The whole outfit would actually be smaller than a current engine because the gas turbine is so efficient and powerful.
Personally I think it is the motor manufacturers/oil companies that have a vested interest in carrying on with current technology - and that's why they have not had the will power to get over these problems.
I think volvo has actually produced a demo car set up like this
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Stephen Khoo
www.khoosys.net
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>> That would be on hell of a car - Gas Turbine, >> heat recovery, steam turbine, water resevoir, condensor, some form of battery >> to store and smooth power flow, and a gas/oil storage tank. >> plus electronics to stop the GT running away with itself. >> >> I'm not sure how many people would want to drive this >> behmoth into London!
Remember that a gas turbine is not the same as a steam turbine - so no water, condensor etc.
Thats true of course but Flat in Fifth was talking about a Combined Cycle Gas Turbine which does include a Steam Turbine - heat recovery from the Gas Turbines exhaust provides the steam for the steam turbine(s).
I think the main reason why these products didn't take of us that GTs do like to run at max and nothing below. I think also that with GTs for electrical generation it can be difficult to control the frequency which in the long term may upset the battery. CCGTs used in commercial power generation have complicated control systems and generally rely on the national grid for frequency control.
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The full story is that the Rover Car Company was the industrial backer for Power Jets Ltd. This was the company founded by the Godfather of the Jet Age, Sir Frank Whittle.
Whittle had patented the gas turbine engine in the 1930s and he was not taken seriously by the Air Ministry at the time.
The work was largely top secret and Rover provided their engineering skills in terms of getting the tolerances right for the turbine fan and also the complex nature of reheat and heat exchange.
Rover built the engines with Power Jets that powered the E28/29 fighter jet.
The result was after the war, the Government saw fit to pass this research to Rolls Royce, in exchange Rover got large engine technology for RR V10 and V12 engines that powered army trucks.
Rover continued with its jet research, it's first car known as Jet1 was a converted Rover P4, this achieved a speed record for a jet turbine car of 155mph on the Bakkebe motorway in Belgium in 1950.
Rover had cracked the complex issues of heat exchange which greatly improved the efficiency of the engine also how to geardown a turbine from 20,000 rpm to drive the rear wheels. They also cracked how to cool the exhaust gas right down to expel it safely from the car.
A number of other cars were prototyped including a four wheel drive coupe and a family saloon, the pinnacle being T4, unveiled at the 1958 Earls Court Motorshow. This was a prototype P6 car, the P6 was planned to carry a jet engine option, hence the traverse front suspension layout to make room. However, a jet engine cost four times to make and despite the obvious amount of power on tap, the fuel economy at best was 16mpg. T4 could top 150mph and it still able today to provide a very good demonstration of jet power.
They even raced two jet turbine cars at Le Mans in 1963 and 1965 with the assistence of the Owen Organisation who supplied BRM chassis with Graham Hill and Jacky Stewart both getting drives.
They finished a respectable 8th and 10th and they were the first and still, the only jet turbine cars to enter and finish Le Mans. In 1965 it was the highest placed British finisher.
Rover jet engines are still used today as reliable drivers for water pumps and also auxilary power units for 747s. Also 40,000 Bhp units were developed to power the ill-fated ATP train.
No other car company in the world ever succeeded to build a gas turbine driven car, many tried with bigger budgets and could not even emulate the success of Jet1.
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Rover jet engines are still used today as reliable drivers for water pumps and also auxilary power units for 747s.
Auxilary power comes fomr a 'mini' jet engine?
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These are my own opinions, and not necessarily those of all Toads.
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Look at the back of some passenger jets just under the tail, you'll see an exhaust, chances are it's a Rover Jet behind the rear bulkhead. Not sure if the more modern planes carry them though.
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On reading about the lag of the engine, it had no gearbox but it was able to reverse the gearing.
There is a book called 'The Rover Story' that chronicles the history of the company. If I remember there's a great section in it about Jackie Stewart feelings about driving the Rover-BRM. It achieved an average of 108mph over the 24 hours, it was more a case of planning each acceleration move carefully but it was very responsive at full acceleration. No **^%!
I bet the rev counter was a sight to behold 0 to 30,000 revs.
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Great precis 3500 - the least I would expect from such a committed Rover fan!
On a minor point of detail - in case anyone goes looking for it on the map, or decides to go for a burn! - the Belgian location for the historic run was Jabbeke - as also used to prove early XK Jaguars.
Jack
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Yeah, sorry bit of a typo there.
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So that was what Rover were capable of and, given the latest X-power proposals, still can do.
Let's hope that there's no further external interference and Rover return to their true potential.
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