Product Summary

A turbine engine manufacturer required an air flow bench capable of testing many different components at low pressure ratios which covered a wide range of flow rates. The test system had to be fully integrated into their manufacturing and quality control processes in order to take advantage of the most current methods of production scheduling and monitoring. The client also required high accuracy and repeatability while minimizing cycle time to achieve target throughput. Improved accuracy would allow manufacturing to produce turbines to the exacting tolerances required by engine designers to lower emission levels.

Feature Summary

  •  Vacuum Flow
  •  Pressure Ratio Control
  •  Customer Shop Floor Information System Integration
  •  Automated system Check and Calibration
  •  Unit Under Test Power Cycling, Communication and Programming Capabilities
  •  Expandable and Flexible and Instrumentation, Data Acquisition and Control sub-system
  •  User-friendly Test System Controller Software for Operator, Maintenance and Engineering personnel

Application Description

Flow Systems designed and manufactured an air flow system that employs a set of seven subsonic Venturis housed in a manifold to meter the air flow through each Unit Under Test. The vacuum bench utilized a venturi manifold to give a much larger flow range than could have been accomplished with any one venturi. The venturi manifold had several venturis arranged with a common inlet and exit manifold and a means of opening or blocking any individual venturi flow path. The manifold was designed so that the flow rate through any one venturi flow path was unaffected by the blocked neighboring venturi flow paths. One set of venturi inlet and differential pressure sensors was shared by all venturis, reducing the number of costly sensors required by the system.

The test stand used the suction side of a blower to draw air through the test part at a precise pressure ratio while simultaneously measuring the resulting air mass flow rate. The mass air flow through the test part created a pressure ratio. The mass air flow rate required to establish the pressure ratio target determines the effective flow area of the passage. One subsonic venturi, from the set of seven, was placed in the flow path in order to measure the mass air flow rate through the test passage.

All test results are saved locally in a test results database, and to the customers production shop floor information system. This allowed tracking of each manufacturing process performed on the part.

System Specifications

  •  Flow Elements: Seven subsonic Venturis
  •  Flow Range: 2 to 1300 SCFM
  •  Test Pressure Range: 1.01 – 1.05 pressure ratio or 5 – 20 INWC (vacuum)
  •  Accuracy: ±0.75 % on effective area and ±0.60% on mass flow, traceable to NIST standards
  •  Repeatability: Estimated better than 0.25 %
  •  Cycle Time: 20 seconds on an average part

System Customization

This product is an example of a custom system developed and manufactured by Flow Systems. System hardware, controller software, fixtures, and facility requirements can all be configured to meet specific customer requirements. Custom test stands manufactured by Flow Systems are built using industry standard Commercial Off-The-Shelf (COTS) components utilize flow meters which are traceable to National Institute of Standards and Technology (NIST).

Photos & Schematics

The following are pictures and schematics of the Combustion Liner/Swirler System.

Combustion Liner/Swirler System
Pneumatic and Instrumentation Diagram
Pneumatic and Instrumentation Diagram

Diagram of Physical Layout
Diagram of Physical Layout