The premiere of the blockbuster Hollywood franchise, full of engines, speed and rollovers, has us wondering once again if it’s possible for a car to crash and then explode.
THE Exploding cars can be fun to watch in action movies. But the cars that turn into balls of fire when they crash or fall down the side of a mountain is one of the most common yet scientifically absurd movie scenes.
With the release of fast and furious 10 , the latest addition to the Fast & Furious franchise on May 19, 2023, It’s time to debunk the myth of the exploding car.
Cars never explode under these circumstances and rarely catch fire. . Unless you were unlucky enough to drive a Ford Pinto either a chevrolet malibu in the 1970s. Both manufacturers took shortcuts in the production process and the result was poorly designed fuel tanks that were prone to catching fire, often trapping occupants inside.
Even when the racing driver Romain Grosjean crashed at over 300 km/h during the 2020 Bahrain Grand Prix, his vehicle caught fire but did not explode.
Gasoline vapors are only explosive in air (What is it 20% oxygen ) and under pressure. Liquid gasoline is not explosive but vapor can ignite. . Steam may escape from the fuel tank when you unscrew the cap. But the tanks have a system in which the pressure is relieved without venting the steam. A full tank of fuel is safer than you think, because there is no air inside and therefore no oxygen.
In fact, liquid gasoline can be difficult to light even in contact with a flame.
What it takes to blow up a car like in the movies
Explosions are normally caused by a reaction in which one or more solids or liquids react and produce a corresponding amount of gas .
A gas takes up much more space (800 times the volume of liquid or solid ) than the equivalent amount of solid or liquid. The force generated by the rapidly expanding gas creates the explosion.
Shrapnel is added to explosive weapons of war, which are propelled by expanding gas.
Gasoline does not explode on its own, but it does explode with oxygen. when in gaseous form it is quite hot (about 257℃) and in the presence of a flame or a spark.
Imagine seeing someone on a hot day filling up their car . Often you will see a glowing effect near the tank filling. It’s gasoline vapor. The “no smoking” instruction on gas station signs and tanker graffiti attempts to eliminate one of three requirements for gasoline to ignite.
Gasoline is a high energy compound. These compounds release a lot of energy when they react with other substances. When gasoline comes into contact with oxygen and burns, it produces low-energy compounds (water and CO₂). The difference in energy between these compounds is seen and heard as sound, heat, light, and force of expansion.
For gasoline to explode (instead of burn), it must be under pressure, in gas form, and have enough oxygen and an external energy source, such as a spark or flame, to start the reaction.
Exploding cars like in Fast & Furious 10
In a car engine, the explosion takes place in a cylinder . The piston compresses the gasoline-air mixture to create the high pressure conditions necessary for an explosion. . When a gas is compressed, it heats up. This is why the tip of a bicycle pump gets hot when you inflate the tires. As the piston compresses the air-fuel mixture, the pressure and temperature increase.
The spark plug provides the small amount of energy needed for the reaction to occur. . This process occurs several thousand times per minute in automotive engines.
Gasoline and diesel can only explode when pressurized and mixed with air and, in the case of gasoline, a small amount of energy is added to them in the form of a spark or flame. The engines pressurize the air-fuel mixture in the cylinder, producing small, contained explosions that spin a crankshaft and spin the wheels.
Diesel is less flammable. Diesel engines use a higher boiling point fuel that burns spontaneously under pressure. , which is why diesel engines do not need spark plugs. Diesel engines too have a slower cycle Compared to gasoline engines, they last longer and offer better fuel economy.
When cars are involved in collisions, fuel lines often break and gasoline spills on a hot engine. Liquid gasoline can ignite in the presence of air. But it cannot explode because it is not under pressure and is in the liquid phase instead of vapor.
In a car crash, diesel or gasoline can sometimes catch fire, but there is no mechanism to create the high pressures necessary for them to explode so it is not.
*Published by The Conversation
Hal Sosabowski Professor of Public Understanding of Science, University of Brighton
Source: Latercera
I’m Rose Brown , a journalist and writer with over 10 years of experience in the news industry. I specialize in covering tennis-related news for Athletistic, a leading sports media website. My writing is highly regarded for its quick turnaround and accuracy, as well as my ability to tell compelling stories about the sport.
