Research On Semi-physical Simulation Technology Of Scramjet Engine Based On High Speed Data Bus

With the deepening of research on scramjet engines in various countries,the research on scramjet engines has gradually moved toward the stage of engineering.The research focus of scramjet engines in various countries has gradually turned to the breakthrough and application of its key technologies.In this paper,the signal acquisition of the scramjet engines is taken as the entry point.The EtherCAT bus technology is used to establish a semi-physical simulation system.The one-dimensional mathematical model of the scramjet engines is established and six degrees of freedom modelis established.The signal of the scramjet engine is collected and the output control command is output.A semi-physical simulation study on a scramjet engine was carried out.Firstly,the paper analyzes the working characteristics of the scramjet engine.By simplifying the working process of the scramjet engine,a one-dimensional model of the temperature and pressure of the key parts such as the inlet,the combustion chamber and the tail nozzle is established and built with Simulink.The model outputs the calculation results of temperature and pressure of the key parts.Then,a semi-physical simulation system for a scramjet is established.First,select the appropriate slave chip ET1100,carry out the design of the hardware ciecuit,including the hardware connection of ET1100 and STM32F7,EEPROM circuit,power conversion circuit,connection circuit of ET1100 and PHY chip,etc.Secondly,use Keil C to write the program of temperature and humidity acquisition and use XMLSpy to write the XML file of the slave station ET1100 configuration,download the C program to the single-chip computer through ST-Link,and configure the required XML file to the slave station through Twin CAT software.Finally,the semi-physical simulation experiment of scramjet engine was carried out.Firstly,the single-station test was carried out,and the temperature and humidity were collected.Then,the second slave system was set up for network test,and then the network was verified.The correctness of the test principle and the feasibility of the system and at last,the six degrees of freedom is simulated.Then the theoretical analysis of the key parts of the test process was carried out,and the data message was intercepted by Wireshark software.The key parameters such as the instructions taken during the test and the time of data acquisition and transmission were analyzed.It shows that EtherCAT bus technology has broad prospects in the application of scramjet engines due to its excellent performance.