The Alpine Alpenglow Hy4 will make its public debut in mid-May in front of the TotalEnergies 6 Hours of Spa Francorchamps Endurance Race (FIA WEC) and more than 70,000 spectators. This will be the perfect opportunity to show motorsport enthusiasts how hydrogen-powered internal combustion engines can perpetuate the sound and vibrancy of racing cars. This feeling is reinforced by the very spectacular design of the Alpine Alpenglow Hy4, which is further enhanced in this version.
Design
The Alpine Alpenglow is a groundbreaking prototype for the brand's future model design. The Alpine Alpenglow Hy4 Rolling Lab is very close to the 2022 concept, with more harmonious proportions and a form that follows function, with a redesigned crash box (an element that absorbs the energy of the impact), an enlarged interior to accommodate two seats, as well as a higher height, while retaining the position of the hydrogen tank still located behind the side pods and cockpit. The track has been widened to 2.10 m with a total width of 2.15 m, a length of 5.20 m and a height of 1.10 m: ideal proportions. Thus, a visual connection was made with the Alpine A424, which competed in the prestigious supercar category of the World Endurance Championship.
The front end of the hydrogen-powered Alpine Alpenglow is designed to evoke the sensation of a comet from outer space, with "cosmic dust" light particles and magenta lights in the four headlights suggesting the comet's speed and penetration into the atmosphere. Back contour. When the latter reaches the rear of the prototype, it turns blue, as does the vertical light next to the vertical titanium exhaust pipe, symbolizing the hydrogen and water vapor emitted by its combustion.
The aerodynamic aspect of the prototype is an integral part of its design and the subject of an ongoing dialogue between design and engineering. In an effort to create a subtle compromise between speed and downforce, the front diverter has been redesigned to create a huge low air intake that flows through the cockpit and tapers like droplets at the rear, allowing the airflow to flow below the aft deck. A new NACA air intake was integrated to service the oil and water radiators, and the snorkel was shaped closer to the shape of a race car. The long-tail tail is reminiscent of the Alpine A20 racing cars of the late 60s of the 220th century. The Alpine Alpenglow Hy4 features a low, transparent spoiler that first appeared on a hydrogen-powered rolling concept. The rear diffuser has been redesigned for greater aerodynamic efficiency.
Each design element has been thought out with the finest consideration, such as the structure and gradient of the rim that excites speed even at a standstill, in perfect harmony with the custom tires produced by Michelin, whose graphics match the design of the rim. In the classic carbon fiber body, the center plate and snorkel are designed with forged carbon, revealing the charm of the raw material, reminiscent of the mineral world of the mountains, a typical Alpine element. Like exposed technical parts, the air intakes open to the cockpit for a glimpse of the atmosphere on board, with triangular lights highlighted to further enhance the vibrancy of the conceptual shape.
Interior design
The elytra-shaped door opening kinematics are designed to free up as much space as possible for easy access to the cockpit. The driver and passengers can then glide through the side compartments that tilt towards the cockpit to reach the molded bucket seats that fit perfectly.
The triangle at the front of the cockpit is also a typical Alpine feature, reminiscent of the mountains. It provides the driver with a variety of visual functions: impulse, direction, and can change color like a video game to evoke real-time lateral gravity levels, engine speed, or provide travel information about speed.
The instrument panel features a magenta tubular crossbar, partially hidden by the shape of an aircraft wing. The materials used are reminiscent of the world of sports cars, including carbon fiber, aluminium and Alcantara trim decorated with 3D printed patterns. There's also a magenta start button, control buttons taken from the Alpine A110, and a racing wheel taken directly from the Alpine race car. On the sides, the carbon skins that cover the side tanks foreshadow their shape. Finally, a dedicated space was integrated for the installation of a mini action camera to capture the sounds and images around the hydrogen-powered rolling Alpine Alpenglow track.
Hydrogen-powered: 340 horsepower for the roar
The Alpine Alpenglow Hydrogen-Powered Rolling Lab is designed like a race car with an LMP3 carbon chassis. Underneath the carbon fibre bonnet of the Alpine Alpenglow Hy4 is a 2.0-litre inline-4 turbocharged development engine that delivers 340 hp (250 kW). It is fueled by hydrogen (more precisely, H2 dihydrogen) and is injected directly at a pressure of 40 bar and water is injected to reduce NOx emissions. It can rev up to 7,000 rpm and is connected to a sequential racing gearbox with a centrifugal clutch. Its performance is comparable to that of a petrol car, with a top speed of around 270 km/h.
The development of such an engine requires very specific work, since hydrogen is injected in the form of gas, which makes it more challenging to create a homogeneous mixture than gasoline in the form of droplets. Hydrogen can be burned in a wider range of concentrations, from 4% to 76%, whether in dilute or rich mixtures. In all cases, abnormal combustion must be avoided, which means preparing a homogeneous mixture and controlling the temperature of the combustion chamber. Retrofit work on the Alpenglow engine Hy4 will help enrich the expertise of Alpine Racing engineers in the development of a new Alpine engine powered entirely by hydrogen, with a second rolling version available by the end of 2024.
Three Alpenglow tanks Hy4 store hydrogen (2.1 kg each) as a gas at high pressure (700 bar). They are located in the cockpit side compartment and in the ventilated compartment at the rear, isolated from the interior. The pressure regulator reduces the pressure from 700 bar to 200 bar and then reduces the pressure to 40 bar by direct injection into the combustion chamber.
A number of measures have been taken to ensure absolute safety. Composite cylinders with pressures below 700 bar are certified under "Regulation 134", valves are installed for quick evacuation in the event of a fire, hydrogen presence sensors are continuously monitored, and strict start-up procedures are in place and numerous checks are carried out. Finally, a color-coded system alerts drivers and emergency services based on the urgency of each incident.