Static stability study of a model rocket

Relevance. When designing flying models of rockets, one of the difficult tasks is to ensure the static stability of the rocket in flight along a given trajectory. Static stability refers to the ability of a model to return to an equilibrium position disturbed by external forces (wind, model asymmetry, etc.). In this case, the model must be stabilized in terms of the angle between the longitudinal axis of the model and the direction of flight (velocity vector), i.e. maintain a zero angle of attack. The condition for ensuring the static stability of the rocket model is the location of its center of gravity ahead of the center of pressure. In this case, when the angle of attack is different from zero, the aerodynamic forces will create a stabilizing moment, which will return the model to a zero angle of attack. The purpose of the study is to develop and compare methods for determining the position of the center of pressure of a rocket and determining its static stability. A simplified method, an analytical calculation, a graphical method, and various practical approaches that can be used in rocket modeling are considered. As research methods, an analytical approach, a graphical method and finite element modeling in the SolidWorks Flow Simulation program were used. In addition, a number of approximate calculation methods were considered. The study analyzes the capabilities of the considered methods for determining the static stability of a model rocket and the error of their application. To confirm the results of the calculation, a computer experiment was carried out in the form of blowing a finite element model of a rocket using the SolidWorks Flow Simulation program. The results of computer simulation confirmed the reliability of the proposed methods for determining the static stability of a model rocket. Research results. Simplified methods for determining the static stability of a rocket are the simplest and most reliable when designing model rockets. It is advisable to use it for launching demonstration rockets with an allowable misalignment error of 15% or more. Analytical methods are useful for designing sports models of rockets with high flight requirements, for example, for international competitions. Conclusion. The proposed method for ensuring the static stability of a model rocket makes it possible to simplify the design process of both demonstration and sports models of rockets for reliable demonstration launches.