Does Gasoline Evaporate in the Fuel Tank?
1 Answers
Gasoline does evaporate in the fuel tank. Since the fuel tank is not a completely sealed device, a ventilation pipe is connected to the charcoal canister to prevent fuel splashing during refueling. The charcoal canister also has a pipe leading directly to the atmosphere. When the fuel tank is well-sealed, there will be minimal gasoline evaporation loss, primarily through the charcoal canister. Below are the relevant details: 1. Between the engine's intake manifold and the fuel tank, in addition to the main fuel supply line, there is a branch line equipped with a charcoal canister. When the engine is not running, the gasoline's evaporation characteristics create high pressure inside the fuel tank. Without the charcoal canister, these evaporated gasoline vapors would be released into the atmosphere through the tank's vent. With the charcoal canister installed, the activated charcoal inside promptly adsorbs these gasoline vapors, maintaining a balance between internal pressure and atmospheric pressure, preventing most vapors from remaining in the system. When the engine is running, these adsorbed fuel vapors are sent back into the engine for combustion via the solenoid valve at the charcoal canister's outlet, making full use of these vapors and improving fuel efficiency. 2. Due to gasoline's volatile nature, a significant amount of gasoline vapor is generated inside the fuel tank. To prevent resource waste and reduce atmospheric pollution, vehicles are equipped with a charcoal canister. Through connected piping, the gasoline vapors in the fuel tank enter the charcoal canister and are stored there. When the engine is running, the stored gasoline in the charcoal canister enters the engine for combustion. In other words, when the fuel tank is well-sealed, the loss of gasoline through evaporation is minimal and is reused.
