An automatic transmission (AT) of a vehicle was compared with a ratio limited Continuously Variable Transmission (CVT). Dynamic model of a passenger car was simulated to compare the overall efficiency of the vehicle equipped with these different types of transmissions. The overall efficiencies were calculated in terms of fuel consumption of the vehicle. The results are based on the Environmental Protection Agency's (EPA) city and highway driving cycles. A Modular approach is taken to model an existing vehicle. The complete model is subdivided into an engine model, road load model, throttle and brake pedal models, and a transmission model. The model is simulated in MATLAB/Simulink software. The automatic transmission model was then replaced by a CVT model and simulated under similar conditions to compare the overall gain in the fuel economy. The simulation results for the automatic transmission closely match with the data obtained from the EPA. The results for the ratio limited CVT indicate improvement in the fuel economy of the vehicle under both the urban and highway driving cycles.
Library of Congress Subject Headings
Automobiles--Transmission devices, Automatic--Fuel consumption; Automobiles--Transmission devices--Fuel consumption; Automobiles--Transmission devices--Computer simulation; Automobiles--Transmission devices, Automatic--Computer simulation
Department, Program, or Center
Mechanical Engineering (KGCOE)
Suthar, Hemant, "Vehicle simulations of fuel economy for an automatic transmission and a ratio limited continuously variable transmission" (2002). Thesis. Rochester Institute of Technology. Accessed from
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