Browsing by Subject "fuel economy"

Now showing 1 - 2 of 2
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    Predictive Optimal Control of Mild Hybrid Trucks
    (MDPI, 2022-10-11) Pramanik, Sourav; Anwar, Sohel; Mechanical and Energy Engineering, Purdue School of Engineering and Technology
    Fuel consumption, subsequent emissions and safe operation of class 8 vehicles are of prime importance in recent days. It is imperative that a vehicle operates in its true optimal operating region, given a variety of constraints such as road grade, load, gear shifts, battery state of charge (for hybrid vehicles), etc. In this paper, a research study is conducted to evaluate the fuel economy and subsequent emission benefits when applying predictive control to a mild hybrid line-haul truck. The problem is solved using a combination of dynamic programming with backtracking and model predictive control. The specific fuel-saving features that are studied in this work are dynamic cruise control, gear shifts, vehicle coasting and torque management. These features are evaluated predictively as compared to a reactive behavior. The predictive behavior of these features is a function of road grade. The result and analysis show significant improvement in fuel savings along with NOx benefits. Out of the control features, dynamic cruise (predictive) control and dynamic coasting showed the most benefits, while predictive gear shifts and torque management (by power splitting between battery and engine) for this architecture did not show fuel benefits but provided other benefits in terms of powertrain efficiency.
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    Vehicle electrification and fuel economy policies: Impacts on agricultural land-use in the United States
    (Elsevier, 2024-06) Dumortier, Jerome; School of Public and Environmental Affairs
    In the United States (U.S.), decarbonization of the transportation sector has important implications for agriculture because approximately one-third of maize production is used for ethanol. For six major U.S. crops, the effects on commodity prices, county-level land allocation, and farm net returns of an increased battery electric vehicles (BEV) market share (including a phaseout of gasoline vehicles by 2035 in a subset of states) and higher fuel efficiency standards for light-duty vehicles (LDV) are quantified. Scenarios are centered around different energy prices, economic growth trajectories, and ethanol blending limits. The results show a decline of maize prices by up to 17.3% if a BEV sales market share in the LDV sector of 100% is achieved in 2050. For the same electrification scenario, total cropland declines by 1.2%–2.2% (depending on the macroeconomic environment) compared to the baseline. There are important farm welfare implications due to spatial differences in land productivity and crops harvested. The potential long-term decline in maize ethanol use is mostly triggered by vehicle electrification and less by fuel efficiency standards. Although bioenergy plays an important role in achieving future energy and climate goals, the role of maize as a liquid fuel is potentially limited.