Uncontrollable combustion characteristics of energy storage oil pool: Modelling of mass loss rate and flame merging time of annular pools

Abstract Hydrocarbon energy storage has a wide range of applications in modern production and life. Regarded as an important form of energy dissipation, combustion plays an important role in energy storage failure. Energy burning rate and flame shape are the key factors of the combustion system. The classic theories of uncontrollable combustion characteristics for energy storage oil pool will be unable to apply to the cases with annular oil pool burning calculation directly, which never been revealed before. The study of oil energy storage burning rate and flame shape characteristics is of great significance to predict and control the energy storage pool transfer between the fuel surface and the unburned area during the combustion process. Experiments were carried out using an annular pool with an outer diameter that used heptane as fuel. Based on dimensionless theoretical derivation, a non-dimensional correlation is proposed the flame merging time. The received energy heat feedback at the center of pool can explain the change of energy mass loss rate, and a dimensional analysis model with Spalding number was developed to interpret the energy mass loss rate in the energy storage annular pool. Experiments show that the characteristic diameter can be well correlated non-dimensionally with all flame height, indicating that the proposed correlation is applicable not only for annular pools but also for solid burners. The study on these issues have the benefit the current utilization and management of the energy storage oil pool.