Bloodhound to blast its way into record books with zero-emissions rocket
Image credit: Charlie Sperring
The Bloodhound LSR team has announced plans to challenge for the land speed record using a zero-emissions rocket as part of the next phase of its programme, following successful high-speed tests in South Africa last November.
The land speed record car has returned to the UK Land Speed Centre, Bloodhound’s HQ in Gloucestershire, after having successfully completed its crucial high-speed tests in South Africa.
These tests took place on the Hakskeenpan: a dry lake bed in the Kalahari Desert, during which the land speed record vehicle notched speeds of 628mph (1,010km/h), placing the Bloodhound LSR car, unofficially, as the sixth-fastest car of all time.
“It was an amazing experience,” Ian Warhurst, owner and CEO of Bloodhound, told E&T. “It was really great to work with a team who are a set of professionals, from all different walks of life and different backgrounds, who all came together with individual jobs and worked fantastically well together to get the car to where it was.”
The alkali playa (flats) was around 20km long. In order to conduct the speed tests, a 500m wide x 16km long strip was cleared of stones, with twenty straight lines painted along its length, creating the desert ‘racetrack’ on which the Bloodhound vehicle was put through its paces.
Driven by RAF fighter pilot Andy Green, the land speed record vehicle reached the maximum speed from a standing start in 50 seconds. He explained how once the car stopped, analysts plugged the car into a computer, taking the hard data off the car to determine its exact speed to the nearest mile.
Speaking to E&T, Green said: “I was the one looking at the speed [in the cockpit], all the data was in front of me. I was looking at a speedometer whilst I was driving, which has marks of 600-650[mph], so based off that, it got up to around 625, but actually it was 628.”
After system analysts had confirmed the actual speed, Green described how he was “absolutely delighted” with the result. “It was pretty much the perfect run in terms of how the car handled the speed we got to and the overall performance of the whole team out there,” he said.
“We were all surprised, even Andy was surprised,” Warhurst added. “Our initial target was 500mph and at that point we were considering success, because we had the data of the car to be able to tell us it’s OK to go at the next level. When we read 628[mph], we were like, smashed it!”
Although the high-speed tests in the South African desert were a resounding success, the team is now turning its attention to raising the vital budget necessary to move into the final phase of the programme: attempting a new world land speed record in 12 to 18 months’ time, back in South Africa. Indeed, in this next phase, data analysis of the high-speed runs will be used to confirm its revised configuration, alongside research into minimising the environmental impact of the project.
The biggest change to the car’s configuration for the land speed record runs will be that there will be a rocket to provide extra thrust. As part of a research programme for the European Space Agency, Norwegian rocket specialist Nammo has designed a compact, zero-emissions rocket to be used as a launch motor to put small satellites (known as CubeSats) into space. The team have expressed how this rocket would be “a perfect fit” for the Bloodhound LSR car and will slot easily into the vacant tunnel beneath the vehicle’s Rolls-Royce EJ200 jet engine.
“Nammo spent a couple of weeks with us in South Africa, they were an integral part of the team,” says chief financial officer, Rick Sturge. “They were seeing how the car was performing, looking at all the data coming off it and working with the engineering team, and Andy from a driving perspective, all just to build a better understanding of the operating characteristics of the car and how their system was going to integrate with other systems on the car to get the right level of performance.”
The Nammo rocket is a ‘monopropellant’ design that uses concentrated hydrogen peroxide (water with an extra oxygen atom – H2O2) as the oxidiser. This is pumped at high pressure through a silver gauze, which acts as a catalyst, causing it to decompose (split apart) into super-heated steam (600°C) and oxygen. The steam and oxygen are channelled through a nozzle to generate thrust. Through this process, there will be no fuel ‘combustion’ and therefore no flame nor any chemically harmful waste generated by the rocket from each run.
Warhurst said: “Nammo has improved their technology so much in the last six to seven years that just the monopropellant will give us enough power to be able to actually give us the boost we need, the thrust we need to get us that land speed record.”
Work is also under way to optimise the auxiliary power unit needed to pump the rocket’s oxidiser. Its originally specified 550bhp V8 internal combustion engine will be replaced by an electric motor and battery pack of comparable power. The team is also exploring the possibility of running the EJ200 jet engine on biofuel instead of Jet A fuel, further reducing the environmental impact of operating the car.
“Today’s technology means that we can use electric motors and battery packs which will give us the power we need. So out with the old V8, in with the electric motor.” Warhurst explained. “This now pushes us onto the edge of electric motor technology.”
He added that by having the battery pack and electric motor embedded, the car would be able to produce a lot of power, and in shorter bursts. It requires a very fast burst and full power of around 400kW for it to be a success.
Chapman also explained how they are already working with a couple of companies in the creation of these all-electric systems. “We’ll be using [kind of] a next-generation battery,” he says. “We need a battery that discharges very quickly, but also charges very quickly.”
The team revealed that recording the data from the vehicle last year was a high-tech process. The Bloodhound LSR car was covered with 192 air pressure tappings, plus a multitude of strain gauges, temperature sensors and accelerometers – these provided data on the pressures and loads that the car was under at high speed. The data from these sensors was reviewed following every run to check if they matched up with the predicted computer-generated CFD (computational fluid dynamics) models and suspension loadings.
At its headquarters - located at SGS Berkeley Green University Technical College in Gloucestershire - Mark Chapman, engineering director of the project, showed E&T the holes in the car that contain the pressure sensors, which were mapped against the aerodynamic models that they had.
“We were using the pressure sensors to look at comparing the analysis we did over the last few years [during trials at Newquay Airport, Cornwall, 2017] to what we were actually getting off the car [in South Africa],” he said.
The data was analysed by Swansea University’s Jack Townsend and assistant professor Ben Evans, who found there was a correlation of over 90 per cent between the predicted CFD model and the data generated. The CFD model also predicted the exact location at which paintwork on the track was stripped from the underside of the car by transonic airflow.
“They’re still number crunching a lot of the detail on the data now, but fundamentally the car performed very well against the aerodynamic CFD models that we had. We were very pleased with that,” Warhurst said. “What this tells us now, with the data that we have, is that this car will break a record".
The next challenge for the analysts is to review the remaining 10 per cent of the data to refine the predictions and to enhance the team’s knowledge of transonic airflow. However, the otherwise high level of correlation has given the team “great confidence” in the aerodynamic shape of the car, describing such correlations as “highly encouraging” as it also meant the prediction models were accurate.
In addition, they confirmed plans to fit winglets to the tail fin to manage the vertical downloads on the rear wheels, “because as the car goes over a certain speed and starts hitting supersonic speeds, the uplift at the bottom starts to increase. We need to put something at the top that will give the car a bit more downforce,” said Warhurst.
The data collected and analysed has also confirmed the drag the car experienced at transonic speeds, crucially indicating the power needed from the rocket to propel the car through the sound barrier (approximately 760mph, 340m/s) and into the record books. This, therefore, means that a 50-60kN monopropellant rocket is required, making Nammo’s development a perfect candidate to further improve on the vehicle.
As part of the next phase of the project, Chapman explains how, starting from this week, the team will strip and clean the car. They will also remove the engine and take it back to Rolls-Royce to get it protected and inhibited. Then they plan to start to look at the rest of the systems in the car: once it’s taken apart, they will be able to see all the stuff they haven’t been able to see in the last few weeks.
However, as Chapman acknowledged, from an engineering perspective the project is still gated by funding. “The next stage of the project needs us to have that finance in place to break that speed record from around June/July 2021,” he explains. “For now, it’ll be a small team working on the car, again, looking at data and all that stuff. When the funding is in place, the whole team will come back in again and then we’ll get prepped up.”
With regard to the project’s next phase, Warhurst agrees: “Now it comes down to sponsorship. We’ve proved that the car has an amazing following, the project itself has an incredibly good social media engagement. If we start sticking a rocket at the back of the car and going down the desert breaking the record there, then we would have a much bigger engagement.”
Warhurst adds that the next challenge is to get more sponsors on board, in hopes to raise around £8m for the project. “Once we’ve got that ‘ring-fenced’, we can then proceed on to the next phase,” he said.
The team remains optimistic about the next phase of the Bloodhound project, with Sturge saying: “I think we’re in a place now where we’ve really established great credibility that we can actually do this thing.”
Furthermore, Green reflects on the reasons as to why the team went to South Africa, to begin with. “From a sponsor point of view, the most important thing was to demonstrate the fact that there is a massive global interest in this,” he said. “Bearing in mind that this is just for high-speed testing, so the interest that we’re going to get when we start setting supersonic land speed records is going to be through the roof.”
He added: “From a business point of view, we’ve demonstrated to the sponsors that they’re going to get exactly what they want out of it.”
Although sponsorships are necessary to help raise funds to continue down the road towards the land speed record, Warhurst explained to E&T how the engineering component of Bloodhound is at the heart of the project: “Engineering is the most exciting part about all of this”.
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