文档介绍：Ultrasound method of solid rocket motor testing
1 ABSTRACT
The solid rocket design engineer requires a multitude of data during
the static and flight test phases of a development program. For instance,
a better knowledge of the behavior of the internal thermal insulator,
especially in the flap zones, is useful for determining the margins of
safety. This is why, besides a heavy work on the modification of the
insulation degradation, ONERA has developed a measurement tool for
determining the behavior of the insulators, this tool is derived from its
own ultrasonic measurement method used in solid propellant
combustion. This technique is direct, non intrusive, based on the
propagation of ultrasonic waves through the materials: case, insulator...
and solid propellant. By following the evolution of the ing back
from the regression surface or the degraded zone of insulator in real time,
many times per second, during the test, one can deduce the following data:
the sequence of events at the measurement location, the starting time of
degradation and ablation of the Insulator and, coupled with
thermo-puting code, the paralysis rate and the heat flux
evolution received on the insulator surface. For solid propellant, the
displacement of bustion front along the insulator is followed and,
of course, its burning rate is deduced.
2 INTRODUCTION
On full scale solid rocket motors, the behavior of the internal
thermal insulator (ITI) and the evolution of bustion surface of
the solid propellant (SP) grain have to be determined during a test for
verifying the predictions. Office National detunes et de Recherché
Aerospatiale’s ONERA has been applying its well-known ultrasonic
method for more than twenty years on solid bustion
studies}-6. This measurement method stands as an industrial control
procedure Explosives at Societies SNPE, Nation ale des the French
have adapted Ponders et propellant manufacturer. We this tool
determining the behavior of the inter