Date of Award
Mechanical, Automotive, and Materials Engineering
AC, active grille shutter, AGS, compressor power
Active grille shutter (AGS) in a vehicle provides aerodynamic benefit at high vehicle speed by closing the front-end grille opening. At the same time, this causes lesser air to flow through the cooling module which includes the condenser. This results in a higher head pressure (AC compressor discharge pressure of the refrigerant). Higher head pressure causes the compressor to work more thereby possibly negating the aerodynamic benefits. This thesis shows a model-based method to quantify the fuel consumption in different scenarios to justify the AGS position (fully open or fully closed) to have better fuel economy. The impact of AGS is more felt at highway speed, so the AGS will be open at low speed or idle. This thesis focuses on the tradeoff between the aerodynamic performance and the compressor power consumption at high vehicle speeds and mid-ambient conditions (26.7°C and 32.2°C). The results from the steady-state simulations show a tiny reduction in the fuel consumption rate for AGS closed condition by comparing to AGS open condition; while the results for the transient cycle show a remarkable reduction in the fuel consumption rate when the vehicle reaches the highest speed of 128.7 km/h. However, at the low-speed range, there is no benefit in fuel economy with AGS closed, as expected.
Yang, Keyuan, "Impact of Front-end Air Flow Conditions on AC Performance and Real-World Fuel Economy" (2018). Electronic Theses and Dissertations. 7588.
Available for download on Tuesday, September 17, 2019