PSI - Issue 71

Anoop Kumar A. et al. / Procedia Structural Integrity 71 (2025) 287–294

293

Fig. 9. von Mises stress of mixer assembly at operating condition

Fig. 10. (a) shows the von Mises stress distribution in the fire face made of copper alloy. Neglecting local peak stresses, global Von Mises stress is 115N/mm 2 and the global equivalent plastic strain is 1.2% (see Fig. 10. (b)).

Fig. 10. (a) von Mises stress in fire face; (b) Equivalent plastic strain in fire face

As copper alloy is a highly ductile material, with a minimum elongation of 40% at operating temperature, the material is capable of bearing the plastic strain without any concern from structural point of view.

5.

Summary and Conclusion

The authors gratefully acknowledge the academic selection committee of LPSC/ISRO for giving permission for presenting this paper in SICE2024. The support given by the Injectors & semi-cryogenic Engines Group is also acknowledged here. We also acknowledge the continuous motivation and encouragement given by Shri. Viswanath for this technical paper. We acknowledge the Director, LPSC for permitting us to publish this paper. The efficacy of the proposed modification was verified for the acceptance pressure test load condition. Stresses and strains on the injector head assembly for operating conditions were evaluated by means of non-linear thermo structural analysis. From the analysis, it is found that the injector head assembly with a modified gas duct is safe and acceptable for both proof pressure and operating conditions. Acknowledgements Finite element simulation has been used to evaluate the structural integrity of the semi-cryo injector head assembly for acceptance pressure test and operating load conditions. Based on simulation results of acceptance test conditions, the original configuration of the gas duct in the injector head assembly was modified by increasing its thickness to an optimum value.

References

Anoop Kumar A et. al. Prediction of Braze Joint Strength of Dissimilar Materials by Numerical and Experimental Methods, 73 rd International