The Relation Between Freeway Average Speed And Speed Noise

Abstract

A significant amount of energy could be saved by applying traffic management policies. Many factors affect the fuel consumption rate, and the most important traffic-related ones include variables such as speed, number of stops, the speed noise, and the acceleration noise. Fuel consumption models for both urban and highway traffic are used to evaluate the effect of these factors. Previous literature shows the speed and the acceleration of the individual vehicles as well as the aero-dynamic effects are the most considered parameters in highway fuel consumption models. However, the existing models are based on the average or cruising speed and the effect of speed variation is not included.Incorporating the speed variation as a variable in the prediction models seems to be impractical because measuring the speed variations is cumbersome. However, since the speed variance and the speed may be correlated, knowing the relation between those two, the speed noise can indirectly be included in the model. Therefore, this study considers the new parameter of speed noise in the Vincent fuel consumption model. Also, in order to practically import the speed noise effects to the model, the relation between speed and the speed noise is evaluated. The equivalency equation of the speed noise in terms of the speed is the new term added to the existing model. This thesis uses freeway speed data collected by TxDOT to find the relation between speed and the speed noise.This study's findings show a strong relation between speed and speed noise. The outcomes also reveal the higher the speed, the lower the speed noise will be. Reflecting on these findings, this study recommends the modified form of the Vincent fuel consumption model for highway traffic.