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More stringent heavy vehicle emissions legislation demands considerably higher performance for engine cooling systems. This paper presents a study of cooling airflow for a Freightliner Class 8 truck. The predicted radiator coolant inlet and charge-air-cooler outlet temperatures are in very good agreement with the measured data. The under hood flow behavior is described and potential areas of improvement leading to better cooling airflow performance are highlighted. The airflow simulation approach is based on the Lattice-Boltzmann Method (LBM) and is described in detail. It is shown that the presented simulation approach can provide accurate predictions of cooling airflow and coolant temperature across different fan speeds.

A commercial vehicle's unexpected deviation from its current lane, often referred to simply as lane departure, can be a manifestation of any number of problems focused on either the vehicle (mechanical or electrical malfunction) or the driver (distraction or drowsiness). To address the topic of commercial vehicle lane departure, DaimlerChrysler Research, Freightliner and Odetics developed Lane Guidance™, a commercially available lane departure warning system. The Roll Advisor and Control (RA&C) Field Operational Test (FOT) as part of the United States Department of Transportation's Intelligent Vehicle Initiative (IVI) offered an excellent opportunity to evaluate the newly deployed Lane Guidance™ System with real world data. The goal of this evaluation was to understand the performance of the system under different environmental conditions such as rain, snow and night/daytime.

Understanding external vehicle aerodynamics is an integral step in reducing overall vehicle fuel consumption. This is particularly true for long-haul commercial vehicles where an incremental decrease in drag can translate into significant fuel savings based on the number of miles traveled over the course of a truck's working life. The ability to critically analyze the air motion adjacent to commercial vehicles is a step toward understanding the overall affects of external aerodynamics on the entire vehicle. To achieve this understanding, the aerodynamics problem must be divided into manageable tasks that can each yield qualitative and quantitative results. A two-dimensional (2D) External Aerodynamics Tool (EAT) has been developed that enables computational fluid dynamics (CFD) simulations of commercial vehicles to be performed quickly and easily.

This paper discusses one method for reducing heavy-duty truck rollover accidents, the Freightliner/MeritorWABCO Roll Advisor and Control (RA&C) System. It describes the operation of this system and the unique way in which RA&C trains drivers to avoid high-risk rollover and braking conditions. In addition, the rationale for this approach is discussed in terms of Behavioral Based Safety (BBS), and the means employed to communicate with drivers is described. A technical description of the RA&C system is presented including a discussion of the challenges of designing and developing this product to be a cost-effective system readily implemented in today's commercial vehicles. Resolution of these challenges leads to the choice of the ABS platform to house and operate the necessary electronics and software along with the Freightliner Driver Message Center for displaying driver information.