Introduction to Combustion Test Stands

A typical combustion test stand consists of Combustion Control System software, Signal Processing equipment, Support equipment and, of course, the Combustion Device to be tested. Each of these components are briefly described below and illustrated at right.

Combustion Control System Software
Combustion Control System (CCS) software features two main components. The first is the User Interface (UI). The UI translates actions from the operator into commands to be processed by the control logic and presents test stand data to the operator in the form of numeric displays and time-history plots.

The second main CCS component is the Control Logic and Data Processing function. The Control Logic controls the test stand either under manual control from the operator, fully automatically, or some combination of manual and automatic control. The Data Processor converts signals between electrical values (eg. V, mA) and engineering units and also performs filtering and averaging of incoming instrumentation signals.

The UI software normally operates on a PC. The Control Logic and Data Processor functions can operate on the same PC, or for increased determinism and reliability, a separate real-time platform such as a National Instruments PXI controller.

Signal Processing Equipment
Signal Processing equipment is hardware that provides power to actuate support equipment actuators (eg. relays); and, amplifies and filters signals from instrumentation (eg. instrumentation amplifiers). This equipment also includes analog to digital (A/D) converters; digital to analog (D/A) converters; and, digital input and output modules.

Support Equipment
Support equipment is hardware that is necessary to supply, in a controlled manner, fuel and oxidizer to the combustion device. This equipment can include fuel and oxygen tanks, pneumatic and solenoid valves, pumps, the igniter, etc.

Combustion Device
The Combustion Device is the chamber in which a chemical reaction occurs to produce a high temperature, and sometimes, high pressure gas.