3D simulations and laboratory experiments to evaluate a dynamic airbag valve

Abstract

Airbag pressure determines the restraint effect during a vehicle crash. The pressure required to restrain the occupant depends on pre-crash detection, collision parameters and the occupant’s mass and position. This work modulated airbag pressure for optimum safety using a novel airbag control valve for cold-gas inflators. This paper evaluates the valve’s stationary and dynamic performances for Helium by 3D flow simulations using a pressure-based solver in ANSYS Fluent® and SAE J2238 laboratory tank tests. The predicted and measured tank pressures for the fully open (stationary) valve were agreed by an average 93.73% with an excellent correlation (correlation coefficient, R = 0.9995). For the first dynamic operation with 10 ms switching time, the results agreed by 92.78% with R = 0.9975. In the second test with 30 ms switching, 83.67% agreement was observed with R = 0.9893. The research concluded that the valve modulates the bag pressure and is implementable in vehicles.

Keywords:

• Automotive airbag
• cold-gas inflator
• airbag control valve
• pressure modulation
• restraint effect

Disclosure statement

All the authors declare no conflict of interest.

Additional information

Funding

This work was financially supported by Bayerisches Staatsministerium für Wirtschaft, Landesentwicklung und Energie (grant no. IUK-1902-0007//DIK0102/01). We acknowledge support from the Open Access Publication Fund of Technische Hochschule Ingolstadt.