Modern car are packed with incredible technology this days. One that is constantly being developed is the ability to burn less fuel. This due to rasing cost of gas as well as meeting government expectation of lowering the CO2 emissions. But how cars that burn less fuel can release less carbon dioxide? Well to put it simple, If car burns less fuel it can travel for longer distance and we don’t have to visit gas station so often. The result lower emissions and usage of gas. Where can we apply changes that will decrease the amount of fuel used? There are couple things to improve such as transmission, fuel injectors, valves, dual-cluth system, tires and many more. Let us consider some of this inovations used in internal combustion engines cars and see how they work.
-Cylinder Deactivation system:
Cylinder deactivation is used to reduce the fuel consumption and emission of an internal combustion engine during light-load operation. In typical light-load driving the driver uses only around 30 percent of an engine’s maximum power. In these conditions, the throttel valve is nearly closed, and the engine needs to work to draw air. This causes an inefficiency known as pumping loss. Some large capacity engines need to be throttled so much at light load that the cylinder pressure at top dead center is approximately half that of a small 4-cylinder engine. Low cylinder pressure results in lower fuel efficency. The use of cylinder deactivation at light load means there are fewer cylinders drawing air from the intake manifold, which works to increase its fluid (air) pressure. Operation without variable displacement is wasteful because fuel is continuously pumped into each cylinder and combusted even though maximum performance is not required. By shutting down half of an engine’s cylinders, the amount of fuel being consumed is much less. Between reducing the pumping losses, which increases pressure in each operating cylinder, and decreasing the amount of fuel being pumped into the cylinders, fuel consumption can be reduced by 8 to 25 percent in highway conditions. To put it simple this technology “turns off” some of the engine’s cylinders when they are not needed. It essentially turns off the valves to some cylinders so that fuel and air aren’t pumped into them.
-Gasoline Direct Injection(GDI):
Also called direct fuel injection, spark ignition direct injection (SIDI)
In conventional gasoline engines, fuel is injected into the intake port and mixed with air while the air-fuel mixture is drawn into the cylinder. In direct injection systems, fuel is injected directly into the cylinder, which makes the fuel-air mixture somewhat cooler. Cooler air allows higher compression ratios and/or more efficient spark timing. This can increase performance and lower fuel use.
-Transmission, additionl gears:Adding gears allows your engine to operate at a more efficient speed more often. The more gearing options your vehicle has, the more efficient it can be.
-Dual Clutch Transmission(DCT):
Dual clutch transmissions (DCTs) combine the efficiency of manual transmissions with the convenience of automatics. Automatic transmissions are less efficient than manuals due to parasitic losses. DCTs operate much like manual transmissions, except that they use two clutches and automatic shifting. They are generally not quite as smooth as regular automatics, but manufacturers are making strides to improve this.
-Stop-Start System:
Also called idle-stop or smart-start. These systems automatically turn the engine off when the vehicle comes to a stop and restart it instantaneously when the the brake is released or the accelerator is pressed. This reduces fuel wasted during idling.
-Low Rolling Resistance Tires:
When rolling, a tire is continually deformed by the load of the vehicle on it. This causes energy loss. Manufacturer changes to tire shape, materials, and tread design can reduce rolling resistance and improve fuel economy.
This are the improvement that are already being used and are constantly being developed. There are also much better ways of increasing the fuel efficiency, for example full hybrids, or mild hybrids cars. In the world of rapid changes we only can imagine how would future look like. Are gas powerd cars going to be displaced by electric, hybrids or hydrogen powerd cars? We will see what future holds.
sources:
https://www.fueleconomy.gov/feg/tech_adv.shtml
Great article, those DCTs are getting more and more popular these days