i thought this was an interesting perspective to look at . Racing in 2025. Some of the designs are fantastic
WTF will racing be like in 2025? – AutoblogGreen
RACING in 2025
October 30, 2008
AUTO BLOG GREEN
October 30, 2008excellent site of green concepts for the future. Wish i had of came across it earlier.
Royal College of Art creates sustainable auto concepts – AutoblogGreen
Greeen car congress
October 30, 2008Quite interesting site documenting healthier more environmental alternative in the car world. Has a blog too which is full of interesting perceptions
http://www.greencarcongress.com
Hydrogen/ethanol powered rotary
October 30, 2008This is the type of drive train we decided upon for our design. Here is a better image and a little run down of how it works if you havnt already taken a look at the posters
here is some information about the motor.
The Wankel cycle. The “A” marks one of the three apexes of the rotor. The “B” marks the eccentric shaft and the white portion is the lobe of the eccentric shaft. The shaft turns three times for each rotation of the rotor around the lobe and once for each orbital revolution around the eccentric shaft.
In the Wankel engine, the four strokes of a typical Otto cycle occur in the space between a three-sided symmetric rotor and the inside of a housing. In the basic single-rotor Wankel engine, the oval-like epitrochoid-shaped housing surrounds a rotor which is similar to a Reuleaux triangle, a three-pointed curve of constant width, but with the bulge in the middle of each side a bit more flattened. From a theoretical perspective, the chosen shape of the rotor between the fixed apexes is basically the result of a minimization of the volume of the geometric combustion chamber and a maximization of the compression ratio, respectively. Thus, the symmetric curve connecting two arbitrary apexes of the rotor is maximized in the direction of the inner housing shape with the constraint not to touch the housing at any angle of rotation (an arc is not a solution of this optimization problem).
The central drive shaft, also called an eccentric shaft or E-shaft, passes through the center of the rotor and is supported by bearings. The rotor both rotates around an offset lobe (crank) on the E-shaft and makes orbital revolutions around the central shaft. Seals at the corners of the rotor seal against the periphery of the housing, dividing it into three moving combustion chambers. Fixed gears mounted on each side of the housing engage with ring gears attached to the rotor to ensure the proper orientation as the rotor moves.
The best way to visualize the action of the engine in the animation at left is to look not at the rotor itself, but the cavity created between it and the housing. The Wankel engine is actually a variable-volume progressing-cavity system. Thus there are 3 cavities per housing, all repeating the same cycle. Note as well that points A and B on the rotor and e-shaft turn at different speed, point B moves 3 times faster than point A, so that one full orbit of the rotor equates to 3 turns of the e-shaft.
As the rotor rotates and orbitally revolves, each side of the rotor gets closer and farther from the wall of the housing, compressing and expanding the combustion chamber similarly to the strokes of a piston in a reciprocating engine. The power vector of the combustion stage goes through the center of the offset lobe.
While a four-stroke piston engine makes one combustion stroke per cylinder for every two rotations of the crankshaft (that is, one half power stroke per crankshaft rotation per cylinder), each combustion chamber in the Wankel generates one combustion stroke per each driveshaft rotation, i.e. one power stroke per rotor orbital revolution and three power strokes per rotor rotation. Thus, power output of a Wankel engine is generally higher than that of a four-stroke piston engine of similar engine displacement in a similar state of tune; and higher than that of a four-stroke piston engine of similar physical dimensions and weight.
Wankel engines also generally have a much higher redline than a reciprocating engine of similar power output, mostly because of the gearing from the rotor to the e-shaft; and also because the smoothness inherent in the circular motion, which eliminates dangerous vibration that can occur in reciprocating engines due to the nature of their operation.
National agencies that tax automobiles according to displacement and regulatory bodies in automobile racing variously consider the Wankel engine to be equivalent to a four-stroke engine of 1.5 to 2 times the displacement; some racing sanctioning bodies ban it altogether.[12]
Hydrogen is extremely flammable, requiring far less energy to ignite than gasoline. Due to this property, hydrogen in an ordinary reciprocating engine is very susceptible to abnormal combustion during the intake stroke due to the high temperature of the spark plugs. Because of this, achieving ideal combustion becomes extremely difficult.
In the rotary engine, the intake chamber is separated from the combustion chamber. This minimizes the risk of abnormal combustion, and makes the rotary engine very suitable for burning hydrogen fuel. In addition, by implementing Mazda’s direct injection technology, the hydrogen rotary engine achieves even better combustion.
By using Mazda’s unique rotary engine technology for the hydrogen rotary engine, we have achieved a harmony between cleanliness and an exhilarating driving experience. Leveraging our long experience in developing combustion engines, we have created a hydrogen engine just as easy to use and reliable as a gasoline engine. Our gasoline rotary engine does not require much modification to equip it for hydrogen fuel, so it can be produced at relatively small cost.
Mazda’s hydrogen rotary engine employs a dual-fuel system that allows it to run on either hydrogen or gasoline. This system not only relieves the driver from the worry of running out of hydrogen, it also makes the car far more convenient because it can travel long distances to areas without a hydrogen station
Massachusetts Institute of Technology Smart Car
October 29, 2008fold away cars! great idea
Autodesk – Sustainable Design – Massachusetts Institute of Technology Smart Car
zero car
October 29, 2008An interesting design from the other design studio zero car, quite unusual
Compressed Air Car « Tim’s Zero Car Concept
