Product Description

An automotive client required an air flow test stand to aide in improving engine design. Accurate air flow measurements through cylinder heads, intake and exhaust manifolds, intake air cleaner boxes, throttle bodies, exhaust piping systems, mufflers, and catalytic converters would be used to develop more efficient engines and improve computer engine models. Speed and ease in setup and use must be maintained for rapid prototyping.

System Requirements

  • Bi-directional flow Capability
  • Dual control modes
  • Precision Engine Valve Positioning System
  • Wide Range of Part Test Pressures and Mass Flow Rates
  • Automated Testing Capability
  • Expandable and Flexible Data Acquisition and Control sub-system
  • Expandable Air-Flow metering system and Instrumentation
  • Automated System Check and Calibration
  • User-friendly Test System Controller Software for Operator, Maintenance and Engineering personnel

Solution Description

Flow Systems designed and manufactured an air flow system that employed a set of five subsonic Venturis. The system includes a flow direction manifold that allows for pressure or vacuum testing of each Unit Under Test. The flow control system is capable of maintaining a constant pressure drop across the test piece regardless of flow rate or capable of maintaining a constant flow rate regardless of pressure drop.

The test system is fully automated.
After the operator enters test parameters and hardware configuration data, the test stand performs the tasks of positioning the valves, controlling pressure or flow rate at the Unit Under Test, and recording all measurements to a database without further human intervention.

The test system was fully integrated with a precision valve positioning system. The valve position system is capable of positioning up to six valves independently through a range of 0 to 20 mm with an accuracy of ±15 µm.

System Specifications

  • Flow Elements: Ten torodial throat design Sonic Nozzles with a binary progression of throat area
  • Flow Element Calibration: ±0.35% of indicated discharge coefficient (traceability to NIST)
  • Flow Element Inlet Pressure Calibration Range: 30 to 130 psia
  • Flow Range: 7.5 to in excess of 15,000 lbm/hr of dry air
  • Flow Stand Accuracy: Estimated at better than ±0.42% of reading
  • Repeatability: 70 psi Estimated at better than ±0.1% (defined as two times the standard deviation divided by the mean of thirty identical samples)

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 Intake/Exhaust Manifold and Cylinder Head.

Intake/Exhaust Manifold and Cylinder Head
Pneumatic and Instrumentation Diagram
Pneumatic and Instrumentation Diagram

Test System Physical Layout

Test System Physical Layout –
View / Download Physical Layout as PDF