A Two-Stage Pressure Boost Device for Relieving Turbocharger Delay Effect by Means of Utilizing Engine Waste Heat 2015-01-2790
Turbochargers can improve vehicle dynamic performance and fuel economy and are applied widely nowadays. Due to the existence of turbocharger delay effect, acceleration delay and insufficient combustion are its disadvantages.
By collecting high pressure gas which generates from the inertia of the turbine in the intake passage when the vehicle slows down, the gas can be supplied for the shortage while the vehicle is accelerating, which can reduce turbocharger delay effect directly. However, turbocharger delay effect changes a little at high speed and low speed which is subjected to the air inflation and short air-release time.
This paper adds a set of pressure booster device on the existing inflating-deflating device, whose thermal energy comes from the compressed air and lubricating oil, to facilitate pressure increasing in inflating-deflating device and help the chamber change sooner, which avails to relieve the delay effect.
The heat source is modeled for studying the turbocharger's thermal load property under different conditions. Relative parameters in the heat exchange system is calculated, combined with the analysis of heat transfer about the heat exchangers for the pressure booster. Then, with the assistance of booster system, the practical effect of relieving the delay in the turbocharger has been analyzed.
The research presents that the pressure booster device can increase the volumetric efficiency significantly under all speed load conditions. The structure of the device is compact and the system itself is self-energized, and would be an efficient compensation for existing devices which are designed to relieve the turbocharger delay.