Inspiration LSR: Full steam ahead
This June, a British car will attempt to break a World Land Speed Record that has stood for 103 years. The car in question has such an achievable-looking target that you wonder how the record has remained intact for so long: it will have to beat 145mph, in the usual two directions, over a measured mileon the runways of an air force base in California.
That wouldn’t be much of a challenge for a reasonably stock gasoline-engined hot hatch. However, this 146mph Land Speed Record car must be powered by steam to earn its place in the history books. And you don’t need a degree in engineering to know that most internal combustion engines don’t run too well on superheated water.
The British Steam Car Challenge started life in 1999, as an end-of-year project set for engineering students at the University of Southampton by Dr. Neil Richardson and Dr. Richard Bowen. Breaking Fred Marriott’s Land Speed Record of 127.6mph, set in 1906 by the Stanley Steamer, has always been its aim. So far the car has run seven times from 13 attempts, but only up to 80mph.
At one point those involved in the project thought they could create a car capable of 200mph; that figure has since been revised to 170mph. Beyond that, though, it’s hoped that this record bid will encourage a generation of engineers to think more freely about alternative fuels – which explains the car’s name.
“Inspiration” measures 24.5ft from the end of its rounded nose to the tips of its tailpipes. It weighs 3.4 tons, and is powered by a rear-mounted 13,000rpm two-stage turbine providing 360 horses to the rear wheels. It has no gearbox other than a 5.5:1 reduction final drive ratio – and no clutch. To get away from rest the car’s engine is started with the rear axle up on hydraulic jacks, which are lowered once the rear wheels are spinning fast enough.
The car’s starting procedure begins with two kettle heater elements, which is strangely apt for a car with the potential to make 9000 cups of tea in just three minutes. They heat the LPG fuel to 480 degrees, and it in turn is mixed with air and used to heat 10.5 gallons of water per minute to 750 degrees via 12 custom-made boilers.
“The boilers contain more than 9800 feet of 4mm tubing,” explains chief engineer Matt Candy. “They’re small, because they have to be portable, and they’re made in several stages, in several different places in the UK. And if we have any failures we’ve only got two spares.”
So will Inspiration be the next LSR record-breaker? “Depends if we can turn the car around, cool it, refill it with fuel and water, charge the batteries and start it again inside 55 minutes,” says Candy.
“Even if we don’t, though, the heat exchange technology we’ve developed has the potential to make all sorts of efficiency improvements to internal combustion engines. So maybe we’ve already made our biggest achievement.”
Former Ford chief technical officer Richard Parry-Jones, who advises the British government on environmental issues, wishes the project well, but doubts that steam power has a mainstream use in road cars.
“The engine that powered the Stanley Steamer in 1906 was a 3.1-liter two-cylinder reciprocating unit, but this type of steam engine has given way almost completely to the more efficient and modern steam turbine,” says Parry Jones. “The Inspiration has a very advanced version of this technology. It produces 360hp, which it will need to achieve the target of 170mph.
“I expect it will do well; the powerplant and vehicle design parameters seem to have been well chosen for the task in hand. But that doesn’t mean steam power will ever be applied in mainstream cars. The reciprocating steam engine is much less efficient than a petrol (gasoline) or diesel, and although it can employ a wider choice of fuels to power the boiler, any that produce ash are likely to be far too polluting and impractical.
“Steam turbines, as used in the Inspiration, are far more efficient than reciprocating ones, but they are much too heavy and expensive for normal road cars. In addition to the normal fuel tank, they require a water tank (the Inspiration uses 264 gallons, weighing more than a ton, every 25 minutes), a boiler which can withstand high pressures safely, and a precision reduction gear to translate the very high turbine shaft velocities to speeds that are usable on the road.”
Parry-Jones says there’s not really anything here for the climate-change crowd, either.
“The use of LPG for fuel is neither novel nor exclusive to the steam engine, so it doesn’t represent a significant CO2 saving,” he notes. “Cleaner combustion emissions are a credible claim, but even this isn’t a compelling advantage; after-treatment systems are deployed cost-effectively in modern diesel and petrol engines.
“So I wish the British Steam Car Challenge team the best of luck. But I don’t expect to see steam engines under the bonnet of any road cars in the near or distant future.”
Words by Matt Saunders/Autocar
Photos by Stan Papior/Autocar