Last week Ford gave us the first look at the fuel cell-powered Fusion that they will be taking out to Bonneville next month to try and establish a top speed benchmark for production bodied fuel cell vehicles. This past weekend a group of twenty engineers and technicians from Ford and Roush took the Hydrogen Fusion 999 to the Transportation Research Center in East Liberty, OH for its first track test as a complete vehicle and they invited AutoblogGreen to stop by.
The Fusion 999 project was born in early 2006 when Ford Fuel Cell Engineering Manager Mujeeb Ijaz approached Roush about doing a project to demonstrate the performance potential of a fuel cell-powered vehicle. Although they initially envisioned using a Focus body shell, once the analysis started it quickly became clear they would need something larger, so they switched to Fusion.
Continue reading the story of the Fusion 999's gestation and see video of the car after the jump.
The team from Roush, led by Rick Darling, worked with a team of Ford engineers and technicians led by Matt Zuehlk to come up with a vehicle design that could meet the goal of exceeding 200mph on the Bonneville salt flats fueled only by hydrogen. Using computer simulations the team determined how much power and fuel would be needed to push a car wearing production Fusion body panels past the double century. Since the car only needed enough range to get through the seven mile course laid out on the salt a number of features normally used on road going fuel cell cars were discarded such as regenerative braking and a battery for parallel hybrid functionality.
Being essentially a drag racer, transient performance is also not really an issue for the Fusion so the battery hybrid functionality wouldn't be of much benefit. Since aerodynamic drag force increased exponentially as the speed increases, a tremendous amount of power is needed to move a car at 200 mph. It was determined that the Fusion would need about 350kW to achieve its goal. The fuel cell engineers at Ford, led by Shazad Butt, used the same type of Ballard fuel cell that's in the Focus FCV and essentially plumbed four of them together to create the stack for Fusion. Prior to vehicle integration the stack was bench tested at up to 336kW, a limit imposed by the electrical load sinks that were available. At full power the system will be putting out about 600A at 600V.
The car itself was designed and fabricated by Darling's team at Roush with the tube frame being built at the race shop in Livonia and final assembly and systems integration being done at Roush's Allen Park, Michigan facility. In order to minimize the drag, Ford's wind tunnel gurus created a sealed off front clip that will use NASCAR style stickers to replicate the Fusion face. Since air can't flow through the front bodywork an alternative method of cooling would be required. The space between the front wheels that's normally occupied by the engine now contains a stainless steel tub capable of holding 400lbs of ice. Enough heat is generated during the course of a three minute all-out run to completely turn that ice to liquid water.
The 999 drives the rear wheels through a stock Ford GT transaxle. In order to accommodate the powertrain, the rear wheels were moved back six inches relative to the front axle. The fuel cell stack is mounted under the floor and the entire car from the B-pillar back is filled with the fuel storage and delivery system. In order to maximize power output from the stack it was decided replace the usual air compressor with an on-board supply of oxygen. After initially evaluating a nitrox mix, the team decided to use heliox (helium-oxygen mix) with forty percent oxygen which was more than capable of achieving the required power. The back of the Fusion has two large tanks of compressed heliox and a 5000psi hydrogen tank containing 4kg of H2.
During the week before the track testing the completed car was dyno tested at Ford's sustainable mobility test lab to make sure the electric motor and drivetrain system worked properly. That testing was done by connecting an off-board electrical supply to drive the motor. Until the car got to TRC the full system of fuel cell and motor had never been run together on the vehicle. When I arrived on Sunday morning the team was completing their final systems checks and putting on the front body work. The just-completed car was still coated in primer for this initial test and will be getting its paint in the coming weeks prior to heading out west.
After rolling the car out of the garage they hooked it up to the push truck for the initial un-powered tests. Before starting the fuel cell stack they used a truck to push the Fusion up to 60mph so that driver Rick Byrnes could test the brakes and steering. Since this car is designed to go in a straight line at very high speeds the steering ratio has been reduced from the usual 16:1 to 40:1 to keep up from veering off course. Since stability is more important than handling on the salt nothing was done to reduce weight and although the team declined to disclose the weight, they did say that no extra ballast was needed as usually happens with LSR vehicles.
Once the un-powered tests were completed they got ready to run the car under power for the first time. They had already run the stack in the vehicle for the first time just idling and now it was time to try it in motion. For safety the entire rear compartment of the vehicle is sealed from the drivers compartment. Because the stack is running at higher than normal pressures to maximize power output there is some hydrogen leakage into the compartment. A purging system consisting of a tank of nitrogen that flows its contents into the fuel compartment is used to force out the hydrogen. Numerous sensors are used to monitor hydrogen levels and shut the system down if a problem is detected.
During the first attempt the nitrogen flow rate was lowered to ensure that it didn't run out but it was set too low and the safety system prevented the stack from starting up. After analyzing the data the engineers determined the problem and changed the flow rate back to normal and got ready to try again with a fresh bottle of nitrogen. A second attempt turned out the same. Ultimately they got the car running under its own power, just not all of it. As it turns out they were actually over-cooling the fuel cell stack causing it to run in a low power mode. They're headed back to the lab this week to recondition the system and modify the cooling system before they hit the track again.
Since no one has ever attempted a land speed record with a fuel cell car before there is no official class. That means the team doesn't have to make a two run within a pre-defined time period for this attempt. If Ford is successful and other teams show interest in future years the Bonneville organizers may create a specific class for such vehicles and there are rumors of at least one and possibly more companies working on their own challengers for next year and beyond. In the meantime, if Ford succeeds this year they will always be the first.