Study On Safety Characteristics Of N₂O-based Composite Fuel

With the development of propulsion technology and the enhancement of environmental awareness,non-toxic,non-polluting,high-performance and low-cost green propellants become an important direction for the development of liquid propellants in the 21st century.N₂O is a new generation oxidant with great potential in the future due to its non-toxic,self-pressurizing and compatibility properties,and it can be combined with alkane and ammonia to prepare green propellant.Based on energy and safety performance indicators,this paper select the stable combustible gas Q to match with N₂O,and the basic safety properties?combustion and explosion characteristics?of several samples were studied.Based on the classic C-J theory,the detonation parameters of the series of N₂O-based composite fuels were calculated,and the combustion and explosion characteristics were carried out.According to the comparative analysis of experimental and calculation results,it can be show that detonation velocity of N₂O-based composite fuels were from 2503m/s to 2539m/s,and the detonation pressure are from 3.8 MPa to 3.91MPa,the composite fuels which 1.9%alkane content has the maximum detonation velocity and explosion pressure.The N₂O-based composite fuels are more easily to achieve deflagration to detonation in plexiglass tube with spiral metallic ring,the flame front forms a symmetrical Tulip structure,the velocity of flame front and shock are 2243.6 and 2508.3 m/s respectively The detonation steady pressures are from 3.55MPa to 6MPa,and the shock wave velocity are 2000m/s to 2500m/s.The composite fuels which alkane content is 1.9%has the maximum flame front velocity,shock wave velocity and pressure,the experimental results are consistent with calculation values.The explosive enenrgy of N₂O-based composite fuels were studied by oxygen bomb calorimeter and detonation heat testing device.According to the results,it can be show that explosive enenrgy increases whic the alkane content within a certain range,the composite fuels which alkane content is 3.8%has the maximum explosive energy which is 5692.32 J/g.The addition of alkanes can promote the energy release of composite fuels.The critical diameter propagation of N₂O-based composite fuels were studied by experiment device.According to the results,it can be show the critical diameter of the composite fuels with alkane content of 0,1.9%,3.8%,5.6%are from1.2mm to 2mm,and the critical diameter of the composite fuels with alkane content of 7.5%is higher than 2mm.In the experimental range,the alkane content has little influence on the critical diameter of N₂O-base composite fuels.