Indian Journal of Scientific Research
  • Year: 2012
  • Volume: 3
  • Issue: 1

Frequency Analysis of Instability Observed in a Large Segmented Solid Rocket Motor

  • Author:
  • Prahalad N. Tenglia1, C.S. Rameshb, K. Viswanathanc, R. Saravanand
  • Total Page Count: 7
  • Page Number: 65 to 71

aDr. MGR Educational and Research Institute University, India. E-mail: ptengli@gmail.com

bMechanical Department, PES Institute of Technology, India. E-mail: csr_gce@yahoo.co.in

cVAST, SDSC SHAR, ISRO, (Retd.), India. E-mail: vmhkv@hotmail.com

dSenior Research Fellow, SF Complex, DRDO, India. E-mail: smrskv@gmail.com

1Corresponding author

Online published on 18 December, 2012.

Abstract

During static testing of two identical large segmented solid rocket motors (SRM-3 & 4), unanticipated small amplitude pressure oscillations and consequent thrust oscillations were observed for certain duration. The purpose of this paper is to give an overview of the pressure and thrust data obtained and the frequency analysis carried out on the test data. The probable cause of the oscillations is also discussed. Frequency analysis was carried out by means of Fast FourierTransform software. Amajor part of this work was carried out on frequency analysis of the data by using FFT software. The analysis revealed that the frequency of oscillations in both motors were very close, i.e., 54.29 Hz for SRM-3 and 55.17 Hz for SRM-4. The fundamental axial acoustic mode frequency is also calculated for these motors to find its matching with the analyzed frequency.

Keywords

Static Test, pressure oscillation, thrust oscillation, frequency analysis