Abstract
Research and/or Engineering Questions/Objective
LPLi fuel system is a system that can meet exhaust gas regulation which is getting stronger recently. Recent release of LPG vehicles adapt this fuel system and customer for this LPG vehicle are limited to handicap, men of national merits, taxi, rent cars, etc industry. But for all of these LPG vehicle that was sold in Korea had cylinder type LPG tank which has a weak point that minimize the usage of trunk space and also when person opens the trunk, the person can see the cylinder type LPG tank to have negativity feeling for ones safety. This research can resolve trunk space to satisfy customer needs by developing donut type LPG tank to replace cylinder type LPG tank.
Methodology
Donut type LPG tank is in spare tire location and tank mounting had been fixed on vehicle frame to have good crash safety. Also donut type LPG tank had considered on crash safety, hardness, vibration, startability, driving performance and more which can be equivalent or better than current system. In concept stage the design had optimized by CAE analysis and system. Validation has been done by part validation, hot & cold field test also heat damage test, system vibration test, crash test to have safety performance.
Results
As a result, to endure burst pressure donut type LPG tank wall thickness increased 15%, material strengthened 20% with tensile strength that had been confirmed meet with regulation and performance. Also minimize opening holes on the tank to avoid deformation and leak. All valve components that needed for the tank had been installed in fuel pump to endure bust pressure. LPG tank mounting method had been analyzed by static and vibration condition. Mounting method had been considered with crash, NVH, vibration durability and more. Also customer negative image of LPG tank reduced as well.
Limitations of this study
This research is considered on Korea LPG vehicle market, so product development based on Korea regulation. Research was targeted on cylinder type LPG tank which is located in trunk of the vehicle to have trunk space efficiency and safety. This research not considers replacing cylinder type LPG tank located in underbody. Also donut type LPG tank optimize to have good fuel volume shape in limitation of height.
What does the paper offer that is new in the field in comparison to other works of the author?
Europe and others already use donut type LPG tank but all are adapted as after-sales modification (tuning). However recent LPG vehicle that have been produced by Renault Samsung Motors adapts donut type LPG tank first ever to assemble in vehicle assembly line. By adapting the donut type LPG tank, vehicle sales and environment-friendly LPG fuel usage can increase and it is helpful in reducing pollution.
Conclusions
This Donut LPG tank development made a contribution on increasing usable trunk space and more for LPG customers needs and increasing Korea LPG vehicle sales which have been decreased from year 2009.
Key Words: LPG; LPLi (Liquid Phase LPG injection); Cylinder type; Donut type; LPG tank;