Design Consideration of Liquid Fuel Tank System with Low Fuel Filling Circuit Position in Automotive Vehicle

Abstract

<div class="section abstract"><div class="htmlview paragraph">Fuel system in a vehicle plays vital role in vehicle as it stores the fuel safely to facilitate vehicle running for desired range. Fuel system being a safety critical component is designed to endure varied environmental conditions and defined robustness for all usage conditions. Liquid fuel system consists of three major systems viz. filling system, storage system and vapor management system. Of the three, the filling system’s major function is to assist proper re-fueling of the storage system. Pre-mature shut-off, spillage and fuel spit back are the three major risks associated to system performance.</div><div class="htmlview paragraph">In general, fuel filling system is connected to fuel tank via inlet pipe which houses a flapper to avoid fuel spillage from filler neck during re-filling operation. Fuel filling creates positive pressure inside the tank which causes the tank to bulge. In the process of regaining the original shape fuel is pushed out of the inlet pipe to neck which might cause spillage. To avoid spillage a one-way valve mechanism (flapper) is added to the system.</div><div class="htmlview paragraph">The filling performance of the system also depends on the height of liquid column i.e., height of fuel neck with respect to breather port in vehicle layout. If neck height is very low with respect to fuel tank breathing port position, addition of flapper causes hinderance in fuel filling. This hindrance further increases if breathing port height with respect to inlet pipe is large. This paper addresses the root cause analysis of the problem and counter measure action plan.</div></div>