## 1 Introduction
In experimental research, it is not always possible to determine the combustion behavior of gas hydrates for actual blocks, units, and systems due to the restrictions of variation ranges and the emergence of effects preventing the identification of certain common patterns [26]. This is why numerical simulation methods are often used to analyze the combustion behavior of hydrates. Thus, for instance, [PERSON] et al. [27] carried out the theoretical research into the combustion of methane hydrate in an opposed-jet porous burner. [PERSON] et al. [27] found that the free burning of methane hydrate was unstable. The flame was often self-extinguished due to the formation of a water film layer or self-preservation phenomena. The kinetics of the methane hydrate decomposition and self-preservation phenomenon was theoretically studied by [PERSON] et al. [28] A new solution to the problem of the laminar combustion of a jet containing three-phase methane hydrate particles was obtained in [29]. The laminar combustion behavior of a methane hydrate vapor jet was determined at different methane-to-water mass ratios in the hydrate particles. The results of modeling the methane hydrate combustion accounting for the decomposition kinetics are presented in [30]. At the initial point of time, the rate of hydrate dissociation in the model that took the decomposition kinetics into account was shown to be higher than in the model that did not [30]. A mathematical modeling of the ignition of a gas hydrate sample by a heated metal cylinder-shaped particle was performed in [31]. The ignition delay times were shown to decrease nonlinearly with an increase in the cylinder surface temperature. Gas hydrate self-preservation increases the ignition delay times. In [32], the combustion characteristics of the hydrated spheres with different gas contents and at different ambient temperatures were studied. It was established [32] that with an increase in the gas content of methane hydrate spheres, the combustion rate, flame height, flame oscillation frequency, and flame brightness increased. The combustion characteristics of the methane hydrate spheres were very similar in the ambient temperature range of 293-303 K. Rise and fall periods were observed in the development of flame combustion. The main part of the flame was bright yellow. Methane hydrate spheres with a high gas content have a high energy density, but are characterized by incomplete combustion. The use of in situ combustion technology for natural gas hydrates is an important direction for future research [32]. A review of the literature found that gas hydrate combustion (at low gas hydrate temperatures) had only been examined in depth for simple hydrates consisting of one type of fuel (usually methane, ethane, or propane). Methane hydrate has the most common structure (sI). The formula of the unit cell is 2D-6T-46H\({}_{2}\)O. Large hydrocarbon molecules form an elementary sII structure (the unit cell formula is 16D\({}_{1}\)-8H\({}_{1}\)36H\({}_{2}\)O) [33]. Naturalgas may also occur with the sII structure [33]. A small concentration of propane (in addition to methane) leads to the transition from the sI to sII structure. A change in the elementary structure and an increase in the number of large cells affect the dissociation kinetics. At a fixed pressure, the equilibrium temperature of double gas hydrates consisting of high molecular-mass hydrocarbons (methane + ethane, methane + propane) can rise significantly when compared with methane hydrates [34]. The specific aspects of the equilibrium curves for the double gas hydrates are conditioned by the fact that their equilibrium parameters at temperatures below the ice melting point may depend greatly not only on the pressure and temperature, but also on the concentration of two different gases [35]. The kinetic constants of complex hydrates (the pre-exponential factor and activation energy for the Arrhenius equations), determining the gas hydrate dissociation, can also depend on the gas concentration ratio.