Research on the Modal Test Technology for the Large Launch Vehicle with Four Boosters

摘要

With the development of space technology, the scale of the large launch vehicle with four boosters islarger and the structure of that becomes more complex, so the modal test on the large launch vehicle with fourboosters is more difficult. Some key technologies on the modal test of the large launch vehicle with four boosterswere elaborated in ths paper.Aiming at the new characteristics of the large launch vehicle which contains largeand complex structures, closely spaced modes and difficult identification of local modes,a series of keytechnologies of the modal test were studied in-depth such as the free-free boundary simulation,the liquidpropellant substitution,excitation to the whole and local structure, vibration response measurements and theidentification of closely coupled mode parameters. Based on the above research results, a range of modal tests of1/10 scale model of a large launch vehicle with four boosters was carried out,which verified and improved themodal test methods.The above research solved some problems of a large launch vehicle modal test and will beapplied to modal tests of a newly developed large launch vehicle.