Reference no: EM133303604

One of the potential issues of using compressed natural gas (CNG) in a vehicle is the potential for breaching the onboard tank in the case of an accident. One way to limit the consequences of a potential loss of containment is to have multiple, smaller tanks. Consider a 10 gal tank that holds roughly 6.0 kg CNG (as methane) when full. If an accident occurs and the tank fails suddenly and completely, could there be a fire as far away as 200 m from the accident (if the extent of a potential fire is at the LFL/2 concentration level)? Because of the sudden failure, assume that the methane cools to 180 K when it depressurizes to atmospheric pressure, but there is no significant mixing with air at the release point. The LFL for methane is 5%. State and justify all of your assumptions for full credit. (Methane molecular weight is 16 kg/kmol, and air molecular weight can be taken as 28.9 kg/kmol.)