## 1 Introduction
However, this type of fuel is prone to generating shock waves in explosive accidents, spreading the ignition source rapidly and causing damage to the surrounding environment. [PERSON] et al. [8] proposed an overpressure prediction model for the safe use of hydrogen energy. [PERSON] et al. [9] investigated the effect of fuel diffusion time on the flame using the FOAM platform and found that the more inhomogeneous the fuel mixing, the more drastically the flame velocity decreases, and the deflagration to detonation development is delayed. [PERSON] et al. [10] investigated how pressure affects hydrodynamic instability in premixed methane-air slit flames by DNS and found that as pressure increases, the flame becomes more unstable, the flame front becomes more wrinkled, and the flame propagation speed increases. For explosive containers, [PERSON] et al. [11] conducted multi-field tests on 40-inch containers to study the structural dynamics of hydrogen during an explosion in large containers and found a linear relationship between peak positive overpressure and displacement during the vent rupture phase. [PERSON] et al. [12] conducted explosion experiments using spherical containers and found that a certain hydrogen composition at the time of the explosion will cause the container pressure and flame velocity to change approximately the same, and the maximum value is not under the same fraction. To investigate the effect of ignition on hydrogen-air explosions at pipe seals and openings, [PERSON] et al. [13] conducted experiments in a 6 m pipe and found that the internal and external pressures of the pipe would be higher when the ignition was located close to the sealed end of the pipe than when it was ignited at an opening in the pipe. In addition, if there are obstacles involved in the process of the explosion, the risk factor will rise sharply, which may result in casualties and other serious consequences. In general, obstacles are usually present in the space where a combustible gas explosion occurs, such as roadway sections, beams, and mechanical equipment. For obstacles that can promote explosive power, a wide range of scholars have conducted extensive design and research on obstacle obstruction rate [14], location [15; 16], shape [17; 18], and material [19; 20]. The obstruction rate is one of the key factors affecting the explosion of combustible gases. [PERSON] et al. [21] found in their study of obstruction rate on the evolution of hydrogen flame experiments that the greater the obstruction rate, the greater the velocity and vorticity, and the more serious the reflux flame. To investigate the effect of the number of obstacles on the explosion of hydrogen, [PERSON] et al. [22] found that there may be a critical number of explosions through large vortex simulations. For the shape of obstacles, [PERSON] et al. [23] conducted explosion test comparisons of quadrilateral, cylindrical, and triangular obstacles, and found that obstacles with a tip had the most significant impact on the explosion. In terms of obstacle distance studies, [PERSON] et al. [24] found that the maximum blast overpressure has a corresponding optimal obstacle distance by combining the literature and calculations. By summarizing the research results of relevant scholars at home and abroad, it is found that most studies focus on the deflagration study of premixed gases without obstacles and the explosion effect of single-component gases under the condition of obstacles. Specifically, there are few studies on the deflagration characteristics of H\({}_{2}\)/CH\({}_{4}\) premixed gases with obstacles. In addition, the coupling effect of obstacle angle and position is also less studied. Therefore, this paper focuses on the study of the coupling effect of the angle and position of obstacles on the explosion of premixed gases to provide a reference basis for the analysis of the consequences of hydrogen-doped natural gas explosion accidents.