Gas Turbine & Centrifugal Compressor Field Test Software Development Marybeth Nored Dr. Klaus Brun Dr. Timothy C. Allison Mechanical and Fluids Engineering Dept. Gas Machinery Conference October 6-8, 2008
About CPEP The Field Test Analysis Software is entitled Compressor Performance Evaluation Program (CPEP). This software is based on the recommendations of the GMRC Guideline for Field Testing of Gas Turbine and Centrifugal Compressor Performance. Software was developed by Southwest Research Institute (SwRI) with GMRC funding and is available from GMRC. The CPEP software can communicate with virtually any data acquisition system via a TCP protocol defined by an Interface Control Document.
CPEP Satisfies Requirements in GMRC Guideline for Field Testing Need for near real-time performance data in field testing of gas turbines and compressors. Verify efficiency, power, fuel flow, capacity, and head. Consider test uncertainty as a key evaluation parameter for the field test (as the field setting is not an ideal environment to test in). - Measurement uncertainties for input parameters must be accounted for correctly. - Non-standard measurement practices or improper test procedures can lead to unacceptably high uncertainties. Kurz & Brun 2005
Key Features of CPEP Gas properties are calculated within CPEP based on one of four accepted EOS models for typical natural gas mixtures: BWR, BWRS, RK, or LKP Calculates isentropic and polytropic efficiency, compressor head, flow, and power, with corresponding uncertainties. Calculates non-dimensional head and flow. Plots all test data on typical compressor performance maps. Allows upload of manufacturer data for compressor performance map. Real-time performance calculations through datalink feature, with option to save average data over user-specified time period.
Key Features of CPEP (Continued) Capability to calculate performance with real-time data acquisition, uploaded data from previous field test result, or off-line manual entry Results are plotted against a user-defined performance map and results may be exported Ability to save and load test configurations (with text-fields to specify compressor station name, test date, and other comments on field test) Support for both English and SI units
CPEP Walkthrough: Operating Data Text fields for test name, station, date Test data and measurement uncertainties may be entered manually here Allows user to switch between English and SI units (screen updates automatically) Read or write test data file
CPEP Walkthrough: Gas Composition Component amounts are entered for typical natural gas mixtures. Previously saved gas composition may be uploaded. EOS model selected from four available models.
CPEP Walkthrough: Piping Geometry Input piping and compressor information Suction and Discharge Piping Elements between test point and compressor inlet / outlet should be entered as loss elements
CPEP Walkthrough: Results Performance results displayed graphically in head coefficient vs. flow coefficient plot Numerical results
CPEP Walkthrough: Export Performance results may be exported to a data file for later viewing Tabulated data to be exported
CPEP Walkthrough: Performance Map Import manufacturer performance maps Display measured data on performance map
CPEP Walkthrough: DataLink Start / Stop Data Acquisition Set averaging period, atmospheric pressure, units Most recent data snapshot and averaged data Performance calculations from averaged data saved to file
CPEP Walkthrough: Help Detailed program an information available under help tab, sorted by topic. Loss coefficients for standard piping elements provided
Summary of CPEP Field test analysis software for both centrifugal compressors and gas turbines Up-to-date algorithms for calculating enthalpies, head, gas properties, efficiency, etc. Four widely accepted EOS and test uncertainties have been incorporated Plot support capability for imported and calculated performance curves Support for real-time or near real-time data monitoring Intuitive graphical user interface in a windows-based environment