Gas Mileage

Factors that determine the Gas Mileage

Ordered to run by 20 mpg to 60 mpg, hybrid cars are configured for maximal fuel economy. But aside from its 2nd source of power, what other constituents can determine gas mileage? Here are those factors,

Size of the engine. It is quite ironical that the more muscular your engine is, the larger and heavier it becomes. So much of the extra power will be applied just to carry the extra weight of the engine. Hybrid solves it by placing a small engine with an electric motor. Moreover, little engine has small cylinders that consume less fuel both at stop and although cruising. This makes hybrid cars a lot of fuel effective. Hybrid car engines are smaller and are significantly lighter, thus reducing the total weight of the car.

Driving condition (with respect to the hybrid car’s internal structure). A hybrid car can either be analog or series. With a parallel drive train, the car runs more fuel efficient on the main road. Series hybrids on the other hand work well in stop-and-go traffic.

Car Design/Aerodynamics. While driving at high accelerates, the car’s engine acts more because it has to push the car through the air. This is called aerodynamic drag. And the faster the car is, the bigger the aerodynamic drag it has to overcome. Hybrid cars forge well both at decelerate and high speed because it’s design to cut through air that abbreviates the drag, thus increasing fuel economy. Low-rolling resistance tires, which are stiffer and inflated to higher pressure level can additional cut the drag and increment the fuel mileage of the car.

Vehicle Weight. When the car is heavy, the engine has to inject more fuel to the cylinder in order to push it forward. So in order to increase fuel economy, hybrid cars are made with lighter materials such as magnesium and aluminum or composite materials like carbon fiber.

Driving habits. Whether you are driving a hybrid or not, driving habits can definitely influence the gas mileage of your car. Hard braking and abrupt acceleration wastes a lot of energy. Even if your hybrid has the regenerative braking system, the maximum amount of energy cannot be recaptured back to your battery. Abrupt acceleration on the other hand requires more power from both the electric motor and the combustion engine which equates to more fuel consumption. To increase gas mileage, anticipate braking distance, step on the brake softly, and accelerate gently.

Electric Propulsion Systems

Electric Propulsion Systems

Hybrids are planning to use electric propulsion systems which prove to be very efficient and also environmentally friendly. There may be various approaches and methods in order to accomplish movement using electric power but the main idea is still the same. These systems are already working and will further help develop alternate fuel.

What is Electric Propulsion?

Electric propulsion is the acceleration of gases in order to produce propulsive thrust through electric and magnetic body forces, electric body forces or electric heating. The electric propulsion system is usually incorporated in rocket science wherein it manages energy enough to produce a powerful thrust. An electric propulsion system is an alternative to nuclear propulsion system. The total thrust is less powerful compared to a nuclear rocket but still enough to produce effects.

According to a number of studies, any engine used as a primary source of such powerful propulsion must produce exhaust velocities of around 10 to 20 km/s. There are also storable chemical systems used in rockets with an exhaust velocity of around 5 km/s but overall is less efficient.

Propulsion systems that do not require energy through chemical reactions are still needed. There are electric propulsion thrusters able to produce exhaust velocities of around 10 to 20 km/s which increases payload and reduces propellant mass. The consequences however, are less powerful thrusters consuming larger quantities of power.

The 3 Categories of Electric Propulsion

Electro thermal propulsion is when the propellant is electrically heated then isentropically expanded through a C/D or convergent/divergent nozzle. The system works as electrical energy heats propellants that produce gases as a result. The gases are sent through the C/D nozzle creating thrust. Catalyzed hydrazine or another neutral gas is used in thrusters like arc jets and resistojets.

Arc jets can also be used to heat the propellants via an electrical arc discharge. The arc in the arc jet is a beam of electrons produced from the cathode tip then gathers at the anode. Since an arc jet has a cathode and an anode, a constrictor is also present which is a narrow pathway between the two charges.

Electrostatic thrusters are also called ion thrusters. These use an ionized propellant accelerated through electric fields applied directly like gridded ion thrusters and Hall thrusters. The technique of propulsion is also known as ion propulsion technique since ions are mainly used in the process. Electrostatic energy is used to produce propulsion.

A Brief Guide to Hybrid Vehicles

A Brief Guide to Hybrid Vehicles

Hybrid vehicles were the stuff of dreams centuries ago. Nobody ever thought that creating a vehicle independent from fuel was possible. Fortunately with the continuing development of hybrid technology, more efficient and practical vehicles have been created. In the recent years the campaign for global warming has brought the attention of the public. Hybrid cars are now becoming steadily popular available in different types from compact sedans to SUVs.

Environmental issues are not the only reason that has made the public favor hybrid cars. Rising gas prices is also one of the major reasons why people prefer hybrid cars than conventional ones. Its also practical in suburban environments where you don’t really need horsepower but gas mileage.

Hybrid vehicles

There are  different types of hybrid vehicles. They can vary from the simplest wheelbarrows to ships. No matter what form they are, these vehicles help in reducing greenhouse and noise emissions. Although these vehicles are expensive due to their unique structures, developments will continue to provide more alternatives to the public. These cars may not compare to conventional ones with a 200 horsepower but why would you need that if you only need 20 in the streets?

The simplest hybrid would be the single wheeled vehicles. These are wheelbarrows famously depicted with sails. This can be seen in Chinese sailing carriages.

The next is two wheeled vehicles. These are usually cycle type vehicles. The best example would be the Moped and electric bicycles. They are powered by an electric motor or an internal combustion engine in combination with the rider’s muscles. This concept was also used in the 1800’s by motorcycles. The electric bicycle can either be a parallel or a series hybrid.

Hybrid vehicles are not just limited to private cars. There are also hybrid power trains used by heavy vehicles. There are diesel or turbo electric buses, railway locomotives, heavy duty vehicles, hydraulic machinery and ships.

In ships a diesel engine drives the electric generator or hydraulic pump which in turn powers one or more hydraulic or electric motors. Sails and engines were early forms of hybrids which may be used again due to rising fuel costs.

More developments are continually being made in hybrid structures and systems for efficiency. Today buying a hybrid car is expensive but it will be beneficial in the long run. It does not just save fuel costs but also removes pollution that can harm the health of the people and take whatever it is left of the environment.