||Oak Ridge National Lab., TN. ;Y-12 National Security Complex, Oak Ridge, TN. ;Aberdeen Test Center, Aberdeen Proving Ground, MD. ;Environmental Protection Agency, Research Triangle Park, NC. Office of Air Quality Planning and Standards.
As part of a multi-agency study concerning emissions and fuel consumption from heavy-duty diesel truck idling, Oak Ridge National Laboratory personnel measured CO, HC, NOx, CO2, O2, particulate matter (PM), aldehyde and ketone emissions from truck idle exhaust. Two methods of quantifying PM were employed: conventional filters and a Tapered Element Oscillating Microbalance (TEOM). A partial flow micro-dilution tunnel was used to dilute the sampled exhaust to make the PM and aldehyde measurements. The work was performed at the U.S. Army's Aberdeen Test Center's (ATC) climate controlled chamber. ATC performed 37 tests on five class-8 trucks (model years ranging from 1992 to 2001). One was equipped with an 11 hp diesel auxiliary power unit (APU), and another with a diesel direct-fired heater (DFH). The APU powers electrical accessories, heating, and air conditioning, whereas a DFH heats the cab in cold weather. Both devices offer an alternative to extended truck-engine idling. Exhaust emission measurements were also made for the APU and DFH. Trucks were idled at a high and low engine speed in the following environments: 32 deg C (90 deg F) with cabin air conditioning on, -18 deg C (0 deg F) with the cabin heater on, and 18 deg C (65 deg F) with no accessories on. ATC test technicians adjusted the air conditioning or heater to maintain a target cabin temperature of 21 deg C (70 deg F). Each test was run for approximately three hours.