An experimental study and numerical simulation to elucidate the effects of environmental parameters on battlefield smokes

Combined Obscuration Model for Battlefield Induced Contaminants (COMBIC) is a widely accepted model in battlefield smoke simulation. However, this model fails to accurately model evaporative losses from disseminated oils as a function of temperature. This affects the predicted quantity of suspended liquid that is actually available for producing the screening effects. This is a critical factor in applications where oil smokes are deployed as obscurant materials.; In this research, a laboratory smoke generator was setup and used to mimic the operation of military smoke generator. A Differential Mobility Analyzer (DMA) and a Condensation Nuclei Counter (CNC) were used to measure smoke number density, droplets size and distribution. Numerical simulation was applied to simulate the dispersion and mass losses of smoke cloud with the initial and boundary condition determined by laboratory experiments. Physical processes, such as evaporation, coagulation, convection and diffusion of droplets, convection and diffusion of vapor species were included as factors influencing smoke mass losses. Results from numerical simulation were then put in COMBIC to account for the effects of ambient temperature on oil smoke evaporation and mass losses. The approach used in this research is not only physically reasonable, it is computationally efficient and maintains the integrity of COMBIC structure.; The COMBIC model, which includes effects of ambient temperature on mass losses of liquid smoke, is validated by comparisons between the modeled results and the pictures of smoke in the actual field.