Research on fire protection of load-bearing structure in rocket launch tower test platform
In addition to the loads applied during the upper rocket launching test,the load-bearing structure in rocket launch tower test platform is also exposed to the high-temperature ablation effect of the rocket tail flame.Therefore,the safety and durability of the load-bearing structure needs to be explored.The Q345-D steel plates coated with high-temperature and ablative fireproof coating is subjected to diagonal flame shrinkage test,the ablation phenomenon,ablation rate and temperature data are obtained.FLUENT software is used to carry out numerical simulation of the shrinkage model with fluid-solid-thermal coupling,the temperature and ablation rate are in good agreement with the test data.The maximal error of temperature is 8.9％and the maximal error of ablation rate is 7.14％.The simulation of the three-nozzle rocket launching test process is carried out by the above method.The surface temperature,spatial temperature and velocity flow field distribution of the load-bearing structure are measured under conditions of different spray volume and fire protection coating thickness.The results show that the high-temperature and ablative fireproof coating has good performance in the shrinkage test.The temperature curve shows four obvious stages:rapid warming stage,cooling stage,gradual recovery stage,stable stage.The thickness of fireproof coating should not be less than 15mm when the cooling spray volume of 1m3/s.For every 0.5m3/s increase in spray volume,the minimum thickness of fireproof coating can be reduced by 5.2mm.When the spray volume is higher than 2.5m3/s,the load-bearing structure does not need to be coated with fireproof coating.
NETL
NSTL
万方数据
