S4B : TPS calibration

Model Engine Calibration Rig

S4B-test bench overview

Typical tests

• Nozzle thrust tests with altitude simulation.
• Direct or reverse jet model engine calibration, with simulation of the wind tunnel test conditions.
• Through Flow Nacelles calibrations.
• Thrust reversers calibrations and jet angularities.

S4B vacuum tank

TPS test - 9 inches test rig

• Cylindrical sealed vessel, diameter 2.5 m, length 15 m.
• Fed by compressed air:
  • two pressure levels, 9 bar and 64 bar;
  • dry and clean air (12 µm mesh filtering, less than 5 mg of water per kg of dry air) with temperature controlled;
  • air storage: 9,500 m³ at 9 bar and 109 m³ at 270 bar.

• Vacuum connection:
  • internal absolute pressure level from 15 mbar to atmosphere;
  • connection pipes (diameter up to 1,200 mm) toward vacuum tanks with adaptable volume between 1,000 and 8,000 m³;
  • possible vacuum setting by ejector effect (Bertin ejector or using the tested nozzle itself).

Test techniques

• Mass flow control and temperature control of the two jets.
• Separate control of the pressure upstream of the fan, of the model engine RPM and of the nozzle exit pressure.
• Test rigs checking using reference nozzles.
• Jet thrust vector measurement (module and angularity).

Measurement

TPS

• Steady measurements = 64 analog channels, 16 bits A/D converter, digital lowpass filtering with a bandwidth from 0.01 to 10 Hz. Steady accuracy ±1 mV, resolution 0.3mV.
• On demand, unsteady measurements = 64 analog channels at 100 kHz per channel. 12 bits A/D converter, digital lowpass filtering with a bandwidth from 0 to 20 kHz (if necessary the number of channels can be increased).
• Steady pressures = 992 channels (by DTC PSI®, system 8400).

Measurement techniques

• Temperature measurement by thermocouples and PT100 probes
• Load measurement by ONERA six components balances (decoupling device for air flow crossing through).
• Sonic throat mass flow meters for the primary and fan jets.

Accuracy

• The uncertainties in the 4" test rig with the Ø 100 mm reference nozzle are (from test campaigns between 1987 and 2009),
• Flow coefficient: ± 0,1 % in 86 % of the test cases,
• Thrust coefficient: ± 0,15 % in 81 % of the test cases.