The Professional Motorsport World Expo (PMWE) was back in full swing this year at Cologne’s Koelnmesse. Focusing on high-end motorsport technologies, it attracts suppliers of the highest calibre, along with some of motorsport’s finest engineers, although like most things in 2022, there was an air of uncertainty among exhibitors.
PMWE 2022
One engine that caught our attention was Italtecnica’s 3.0 litre V6 twin turbo. About 15 road-spec units have been supplied to an Italian restored supercar, but on display was the first prototype of the competition version, with the aim of attracting Le Mans Hypercar teams.
The engine features a sequential twin-turbo layout along with a patented passive pre-chamber ignition system. “We have developed the sequential twin turbochargers so that at low rpm the ECU closes a bypass valve which switches off one turbo and allows the gases to bypass to the second turbo, reducing turbo lag,” explained Riccardo Breda. “At high revs, the ECU opens the valve, allowing both turbos to operate in parallel to achieve high power.
“Another unique thing about this engine is the pre-chamber ignition, and initial single-cylinder tests are currently achieving 40- 45% thermal efficiency at most of the engine’s operating points,” added Carlo Cavagnero.
“Our patented design of the pre-chamber allows us to avoid misfiring at low load and rpm by careful placement of the spark plug and optimising the turbulent flows. “This results in the possibility of burning very lean mixtures, in the range of lambda 1.7 to 1.8 at partial load without the need for a secondary spark plug. Overall, our target is to build a simple and affordable system that could be retrofitted on existing engines with minor modifications. We are also studying e-fuels, with promising results.”
Layout of Omni Powertrain’s ETCR electric powertrain
Omni Powertrain had an impressive stand that featured its ETCR powertrain alongside a Hyundai Veloster N touring car. Capable of providing 500 kW of peak power at 800 V through four axial flux motors at the rear axle, the powertrain’s inverters, motors and gearbox were developed by Magelec Propulsion, a division of Omni Powertrain Technologies.
“The motor can spin at 14,000 rpm, and our gearbox drops the speed down to almost one-fifth of the motor speed,” Vincenzo Vanni told us. “Electronic torque vectoring is used to vary the power and speed to each rear wheel via a half-shaft, helping the car to achieve top speeds of more than 270 kph (168 mph).”
Alongside the motors and gearbox, Omni has developed a brand new inverter for ETCR’s second season, in 2022. ”We use silicon carbide technology in our inverter, along with some of the best MOSFETs available on the market,” said Vanni. “I would say 49.9% of the inverter’s performance comes from the choice of materials, and 50.1% from the expertise of our engineers.”
To achieve the high efficiencies demanded in electric racing, managing the temperatures of the batteries, inverters and motors is essential. Omni currently use a water-glycol coolant that flows through machined channels in the motor and inverter casing.
“Soon we will introduce a new technology that will allow us to achieve higher performance while cooling both the inverter and motor a lot faster,” Vanni revealed. “That will use a similar principle to our current system, but we will use a different fluid with a higher thermal capacity that can reject more heat in less time.”
Monolith was a new exhibitor at this year’s PMWE, and showcased its no-code AI software platform for reducing the amount of testing during engineering product development. Its self-learning models have allowed teams such as Jota Sport to predict results from wind tunnel and track tests, which has cut testing times by up to 80%. This has helped to optimise the Jota car’s set-up in half the time, with both cars finishing on the LM P2 podium at Le Mans in 2022. The AI software can also be applied to powertrain testing to save time, resources and money.
“Our platform enables engineers to solve their most intractable physics problems through machine learning [ML],” explained Sam Emeny-Smith. “These are problems to which we don’t have a known solution. “Take track testing for example. Teams can run simulations but they can’t be 100% confident about the results, so they conduct iterative tests at a race until they run out of time or money. However, self-learning models can be used instead to interrogate existing test data and predict the results of tests that have never been completed, helping engineers make more informed decisions.”
The software essentially takes existing data and uses ML techniques such as regression models, neural networks and deep learning, to fit complex equations to that data. It may feel strange to build a model without defining engineering principles, but because the model is based on real test data, the laws of physics are inherent within the data and therefore captured by the model.
“We put a lot of effort into developing trustworthy models,” Emeny-Smith added. “We quantify the uncertainty of models in both a mathematical sense and as a dynamic response. “For example, if you produced a dynamic temperature response over time, we show the uncertainty at each individual point within that curve. It may be that for the first 10 seconds the data is only 80% accurate because the input data was unrepresentative. But from 10 to 40 seconds, it is 98% accurate. That gives engineers context to the data they are analysing, so they can trust the results with high accuracy or decide to collect more representative data for the less accurate areas of the model.”
Monolith’s platform was recently used by Kistler to optimise the fuel consumption of a new engine design. Normally, parameters such as the air-to-fuel ratio, charge time and intercooler would have created a huge matrix of design of experiments that required physical testing. However, Kistler conducted a range of tests across the design space and then used Monolith’s software to develop a model that could predict the results of the other test cases. This reduced the total testing time by 70%.
“The same approach can be applied to dyno testing, fatigue testing and battery testing,” said Emeny-Smith. “That’s why our software is so innovative, because it is agnostic regarding the type of test. It doesn’t matter what the parameters are, our algorithms use existing data to learn the domain. By then applying the expertise of engineers, the produced results can help solve some of the hardest engineering problems.”
For the first time at PMWE, flowmeter specialist Allengra exhibited its range of ultrasonic flowmeters.
They consist of two ultrasonic transducers located at either end of a tube. An ultrasonic signal is emitted from a transducer at one end, and the time it takes to travel through the fluid and reach the transducer at the other end is measured. This transducer then emits a signal back that travels in the opposite direction, and the difference between the two times determines the flow rate of the fluid.
The ultrasonic fuel flow sensor from Allengra has a dual-channel layout that helps achieve accuracies of ±0.5%
“The beauty of this technology is that it has no moving elements, so it works effectively even in the harsh environment of motorsport,” said Magnus Manderbach. “Typically these types of sensors have accuracies of 2-4% of the measured value, but our motorsport design achieves ±0.5%. That’s because we use two ultrasonic channels that measure independently of each other and then take an average for a more reliable result.
“We have also chosen a frequency of 4500 measurement points per second, compared with the more common 80-100. That makes it extremely robust against manipulation, and is one reason why our fuel flow sensor was recently approved by the FIA.”
A further benefit of ultrasonic technology is that the principle works regardless of the fluid it is measuring. Once calibrated correctly, the sensor can measure the flow rate of a range of fuels as well as liquids such as water and glycol mixtures for EV cooling applications, and even hydrogen gas.
“Measuring gases presents some challenges, particularly hydrogen as it has a very low density and can cause issues with materials,” Manderbach said. “However, we have designed a gas flow meter that can distinguish between different gases, which means it can be used for air intake and exhaust measuring as well as hydrogen fuel cells.”
One championship-winning engine on display at the expo was Swindon Powertrain’s 2.0 litre direct injection turbocharged BTCC I4 that powered Tom Ingram’s Hyundai i30 Fastback to the 2022 Drivers’ title. After supplying the official TOCA engine since the introduction of the NGTC regulations in 2011, Swindon Powertrain decided to develop a bespoke unit for the EXCELR8 Motorsport team as the series went hybrid for 2022.
“The base engine is quite a classic one really, a four-stroke with 86 mm bore and stroke, and direct injection with the injector positioned underneath the inlet port,” explained Raphael Caille.“The turbocharger insulation and exhaust manifold design are quite conventional, and all outside the cylinder head, which helps performance because it’s all about storing the energy from the turbine in the best way possible so that we can put it back into the engine efficiently.”
However, the most interesting aspect of this engine is the intake system, which was 3D-printed. “We’ve used 3D printing for more than 10 years when developing parts, but this is the first time we have manufactured and homologated a major engine component using the technology,” Caille said.
“It has allowed us to design features that can’t be manufactured using traditional methods. The challenge though is selecting the most appropriate material, which for a part such as the intake system can be quite complicated. “The material needs to withstand temperatures of more than 130 ºC, along with severe vibrations and shocks, and the sealing property of the material needs to be spot-on. With nearly 2 bar of boost pressure inside the plenum it cannot be allowed to leak, which can be a risk with 3D-printed parts.”
Transmission technology was well-represented, with Hewland, Sadev and Xtrac all having large stands showcasing their latest transmissions for hybrid and electric vehicles. On the Hewland stand was the PEVT dual motor torque vectoring transmission for motorsport. Weighing only 18 kg, it can transmit up to 300 Nm of torque and a maximum of 2000 rpm per side, resulting in a combined potential output of 500 kW.
Another EV transmission on show was the new Sadev S-EV90 gearbox. “The Rx2 and Formula E categories, among others, have allowed us to gain some experience in developing our own reducer and thus complete our product range,” Regis Lefeuvre said.
“It is a compact and lightweight unit that can work with a range of electric motors in different applications, and it can be integrated on the front or rear axle,” he added. “The greatest challenge with this product was to achieve a high level of efficiency and reliability that would meet the needs of electric motors with high engine speeds and peak torques.”
Arguably the most innovative gearbox on display was Xtrac’s P1359 LMDh transmission that will begin its racing career in 2023. Like the category itself, this box has had to satisfy many different parties. Xtrac has not only had to package two different powertrains onto one transmission, it has also had to make it suitable for bothsprint and endurance racing while meeting the needs of four chassis constructors as well as the IMSA and ACO regulations. The gearbox has therefore been in development since 2019, and almost every component has been redesigned.
Xtrac’s LMDh hybrid gearbox features a lot of suspension pick-up points to suit all four LMDh chassis constructors
“It’s a transverse seven-speed sequential gearbox with a limitedslip differential,” said Nick Upjohn. “It brings in drive from the Bosch MGU through an additional geartrain that then powers the rear wheels. We’ve also designed it to allow for a variety of engines, ranging from 6500 to 10,000 input rpm.
“Packaging two powertrains with inherently different characteristics and making them work together is a real challenge. As well as the drive and coast loads of the motor, you also have to consider the severe torque spikes when you connect the motor to a combustion powertrain which has gearshifts. For example, on a downshift you can get a large increase in revs over a very short period of time, so you have to accelerate that motor, which generates a large torque spike.”
The variety of tracks also presented headaches for the Xtrac designers. “Exiting the banking on the last corner at Daytona in seventh gear and then coming straight into the pits can cause serious heat soak issues,” said Upjohn. “We worked closely with Bosch to help cool the MGU by integrating cooling channels for the coolant lines around the front of the hybrid drive casing.
“That’s another example of how challenging it was to meet the needs of four different constructors. Some of them wanted cooling channels on the left-hand side, others wanted them on the right, while others wanted one on the right and one on the left. Trying to juggle all those requirements and fit everything onto the casing, which also houses the hybrid gears and lubrication system, made this bit the most challenging to design.”
Once the base design was finalised, Xtrac developed a second version of the casing that shaved almost a kilo off the original version. This was achieved through more aggressive light-weighting features wherever possible. The total package, including the MGU drive geartrain, weighs 78 kg.
“You don’t want a heavy gearbox, because the heavier the car gets, the higher your crash and suspension loads are,” Upjohn explained. “The higher your crash loads, the stronger and therefore heavier your materials need to be. Originally we were considering making this box out of aluminium, but we have managed to use magnesium instead, which is much lighter, although we have had to focus on the design details to ensure the strength and integrity of the casing.”
Historic racing is not often represented at trade shows, but as this category continues to grow, so does the demand for materials, parts and services. Unfortunately for historic racers, the parts needed are usually out of production or are extremely rare, and are therefore expensive.
With that problem in mind, Con-SEPT attended the expo to explain how it has invested in reverse engineering to recreate new versions of old parts that use modern materials, coatings and surface treatments.
“When these parts were originally produced they did not have the benefit of modern technology,” explained Ralph Geraets.“For example, the surfaces of some engine and transmission parts would originally have been ground, but now we can machine the surface with such high precision that we don’t need to grind the part at all.”
Con-SEPT has reverse engineereda sliding bush for the rear axle of a1960s W108 Mercedes-Benz
Con-SEPT specialises in developing and manufacturing valvetrain components, mechanical car parts as well as test rigs and gauges. On its stand was a sliding bush for the rear axle of a 1960s W108 Mercedes-Benz it had reverse engineered.
“The issue with the original part was cracking, so once we had 3D-scanned a sample from a customer, we did some FEA calculations to see if we could adapt the materials or the design to achieve a higher performance,” Geraets said. “We then made a 3D model to check the tolerances and then produced a small run of 10 pieces that were tested on the real car before going into full production.
“The original part used to be three pieces, but we can now manufacture it from solid,” he added. “We have also managed to increase the wall thickness slightly without changing the outer dimensions, and we have used different materials with different heat treatments such as a special case hardening. That has enabled us to make the outside of the part extremely strong, while the inside remains softer but still has a high tensile strength, making this version more robust and reliable.”
The final design of the sliding bush has been rigorously tested on a number of customer cars and has showed no signs of wear after more than 10,000 km.
Van der Lee launched a new 1050 ºC-capable, ball bearing 250- 400 bhp turbocharger aimed at medium to high-powered single and twin-turbo applications such as 2.0 litre rally or rallycross.
“Ten years ago, this size of turbocharger would have been capable of only around 250 bhp, but by optimising the aerodynamics of the compressor and turbine wheel designs, we can now achieve higher efficiencies and 400 bhp,’ Chris Davies told us.
“We have spent a lot of time developing the design of the compressor housing so it could be machined in one piece. That has made it easy to adapt a wide range of compressor options,reduced the need for tooling parts and reduced the overall weight to 3.5 kg – half the weight of a typical automotive turbocharger of a similar size.”
Van der Lee has managed to achieve this low weight in a costefficient way. A motorsport turbocharger of this type would normally cost around €5000, but Van der Lee’s costs half that.
“We’ve developed our supply chain to be able to produce high quality, lightweight, machined parts at reasonable prices,” said Davies. “The backplate for example is normally quite thick, because it has to withstand a lot of stress. Although it is relatively cheap to manufacture, there is quite a lot of weight there. “We refined the design to integrate ribs for added strength, which then meant we could remove additional material. We also used aluminium instead of steel to begin with, and because we are using an existing centre housing, water-cooled with a ball bearing, we can achieve this low weight at reduced costs.”
Druck displayed its PMP4400T combined pressure and temperature sensor for the first time. It integrates the technology used in its PMP4400 series of pressure sensors with its in-media PT1000 temperature probe.
Druck’s PMP4400T combined pressure and temperature sensor
“High-end race teams are increasingly using combined sensors, as they enable simplified and reduced wiring harnesses,” Michael Thomas said. “The combined pressure and temperature sensor also provides a weight advantage, while multi-parameter measurement at a single point delivers better quality data for performance optimisation. Long-term reliability is the key to winning races, so we focused the design of the PMP4400T on achieving that.”
Another innovative technology that RET spotted at the show were HXLIFE foils. Developed by Reaction Engines, which specialises in thermal management systems and heat exchangers, the foils are designed to sit between the cells of HV batteries or around power electronics to extract heat from surfaces and remove hotspots.
Like all electronic components, batteries have an internal resistance and so heat up whenever a current passes through them,” Alex Creak explained. “Also, the heat generated by a battery cell is proportional to the square of the current passing through it. “That means the faster you try to charge or discharge a battery cell, the amount of heat rejection required to keep the cell from overheating spirals. Put hundreds or even thousands of cells together in a battery pack, and precise thermal management across the packbecomes a real challenge, especially as the industry pushes for higher and higher charge rates.”
Left: with conventional solutions, the characteristic gradient of conductive heat transmission causes thermal stress; middle: HXLIFE foils remove hotspots through direct energy exchange between unconnected areas; right: isothermal conditions are achieved across the surface of each cell, allowing uniform thermal management
Conventional cooling strategies predominantly use cold plates – metallic heat sinks that contain channels of circulating coolant that are attached to one or both sides of a battery pack. However, they only cool the sides of packs, which can result in significant thermal gradients, which limit the maximum charge/discharge rates and accelerate battery degradation.
Other techniques involve complex networks of cooling channels between each row of cells or immersing the entire pack in a nonconductive oil. However, they are complex to design, expensive and come with a weight penalty. “Our foils simply slot between the battery cells, interfacing with the existing cold plate,” Creak said. “That allows the heat to be extracted from each row of cells without any of the added complexity of individual water channels or immersive cooling systems.”
The foils contain a vapour chamber in the centre layer, effectively working like a two-phase heat pipe, spreading heat across the surface of the foil. That can achieve up to 50% more heat rejection than conventional cooling systems, as proven by recent independent testing at engineering consultancy Horiba MIRA, in the UK.
In the test, a battery module with a water-glycol cooled cold plate mounted on the side, and aluminium plates between the cells, was charged and discharged through standard drive and charging profiles. The aluminium plates were then replaced with foils, which showed up to a 50% higher heat extraction and reduced the cell temperature gradient to ±0.5 ºC across the module.
“Thermal transfer across the foil face is very good under normal operational cases, and the foils are resistant to extremely high heat fluxes during thermal runaway scenarios,” Creak said. “That means they can reduce the propagation of a thermal runaway event throughout the battery pack. In fact, initial trials show that the foils double the time it takes for a fire to propagate from one cell to another.”
The foils are not only more effective at extracting heat than conventional cooling systems, they also improve battery pack safety through their response to thermal runaway events. They also increase system lifetimes owing to the reduction of cell as well as pack temperature gradients.