Engineering topics
Publications and source records attributed to Stephens, Julia.
This presentation documents the use of the GRC Low Speed Compressor Facility in the Engine Research Building (ERB) W8 to test low pressure ratio fans. Current capabilities are detailed as well as upgrades underway to better understand low pressure ratio fans. Additionally, the use of StreamVanes for studying boundary layer ingestion in to fans is discussed.
This paper presents methods and results of a detailed measurement uncertainty analysis that was performed for the 8- by 6-foot Supersonic Wind Tunnel located at the NASA Glenn Research Center. The statistical methods and engineering judgments used to estimate elemental uncertainties are described. The Monte Carlo method of propagating uncertainty was selected to determine the uncertainty of calculated variables of interest. A detailed description of the Monte Carlo method as applied for this analysis is provided. Detailed uncertainty results for the uncertainty in average free stream Mach number as well as other variables of interest are provided. All results are presented as random (variation in observed values about a true value), systematic (potential offset between observed and true value), and total (random and systematic combined) uncertainty. The largest sources contributing to uncertainty are determined and potential improvement opportunities for the facility are investigated.
Overview of the measurement uncertainty process at NASA GRC. Examples drawn from the 8 by 6 SWT analysis.
This presentation provides and overview of the measurement uncertainty analysis currently being implemented in various facilities at NASA GRC. This presentation includes examples pertinent to the turbine engine community (mass flow and fan efficiency calculation uncertainties.
An overview of the measurement uncertainty analysis process utilized at GRC to determine the uncertainty of aeropropulstion facilities. Examples are given, but no real findings are presented.