I was trying to emulate a packed bed reactor, and apparently the pressure midway at the packed column became zero, until my numerical method failed altogether (as the pressure variable in the Ergun is at the denominator). I'd like to be enlightened about one thing - does this phenomena (zero pressure midway the packed column) has something to tell me at what will happen at the end? No gas flow or something, perhaps? Thanks. EDIT: Sorry for the title spelling error, it's 'resulting', not reulting.