Description / Abstract:
The methods presented in this SAE Recommended Practice apply to
the controlled testing of low-temperature charge, air-cooled,
heavy-duty diesel engines. This document encompasses the following
main sections:
a. Definitions of pertinent parameters
b. Vehicle testing to determine typical values for these
parameters
c. Description of the setup and operation of the test cell
system
d. Validation testing of the test cell system
While not covered in this document, computer modeling of the
vehicle engine cooler system is recognized as a valid tool to
determine cooler system performance and could be utilized to
supplement the testing described. However, adequate in-vehicle
testing should be performed to validate the model before it is used
for the purposes outlined.
The procedure makes references to test cycles that are
prescribed by the United States Environmental Protection Agency (US
EPA) and are contained in the Code of Federal Regulations. The
existence of other international test cycles, which can be used for
validation testing, is acknowledged.
Purpose-The primary purpose of this document is
to aid in the setup and evaluation of a low-temperature charge
air-cooler system for use with heavy-duty diesel engines (HDDE) in
dynamometer test cells. These charge air-cooler systems typically
provide cooled, charge air temperatures lower than jacket water
after cooled systems but above ambient temperature. Examples of
low-temperature charge air cooler systems include air-to-air
after-cooled and low-flow coolant after-cooled systems. While this
document addresses emissions evaluation of such engines, it is not
limited to that use.