Calibration Considerations for Six Sigma™ Accuracy and Precision in Combustion Pressure Measurement 2017-01-0391
Precise and accurate internal-combustion engine pressure measurements are typically built upon extremely low level piezoelectric sensor signals acquired in the laboratory. In turn, these minute signals must be accurately conditioned using electronic charge amplifiers and then processed for meaningful analysis.
Laboratory standard operating procedures often overlook the importance of timely and rigorous calibration of the equipment, or perform them without using sufficient environmental controls. In some facilities, years have been allowed to pass between metrology-quality calibrations, introducing the potential for significant out-of-tolerance conditions and non-compliance when compared to accredited measurement standards. Environmental, aging and operator factors influencing calibration metrology and in-use accuracy are presented in this paper, along with a method and example for estimating the calibration interval needed to specify calibration frequency for charge amplifiers.
Accurate and timely calibration of combustion analysis or “indicating” equipment supports the validity of using engine incylinder pressure data for engineering design decisions. Quality calibrations, for example those which are done to ISO 17025 standards, help avoid the complications and costs of development program timing delays. These delays can often be the result when additional unplanned testing becomes necessary due to out-of-tolerance measurement equipment and laboratory non-compliance to requirements.
Citation: Meyer, D., Maehling, P., Varghese, T., and Lewis, J., "Calibration Considerations for Six Sigma™ Accuracy and Precision in Combustion Pressure Measurement," SAE Int. J. Commer. Veh. 10(2):508-517, 2017, https://doi.org/10.4271/2017-01-0391. Download Citation
Author(s):
Daniel Meyer, Peter Maehling, Thomson Varghese, Jeffery Lewis
Affiliated:
AVL Test Systems, Inc.
Pages: 11
Event:
WCX™ 17: SAE World Congress Experience
ISSN:
1946-391X
e-ISSN:
1946-3928
Also in:
SAE International Journal of Commercial Vehicles-V126-2, SAE International Journal of Commercial Vehicles-V126-2EJ
Related Topics:
Amplifiers
Calibration
Combustion and combustion processes
SAE MOBILUS
Subscribers can view annotate, and download all of SAE's content.
Learn More »