Emulsified fuel stabilized by comb-type ternary block copolymers for drag reduction and heat transfer enhancement

Turbulent flow in high-speed hydrocarbon fuels increases engine resistance and pump load, leading to higher power demands and reduced reliability. Current drag reduction agents often worsen heat transfer performance. To overcome the contradiction between drag reduction and heat transfer deterioration, comb-type ternary block copolymers, hexadecyl methacrylate-co-dimethylaminoethyl methacrylate-co-methacrylic acid, have been designed and synthesized through photoinitiated polymerization and used as emulsifiers to prepare emulsified fuels. The emulsions with different compositions of JP-10 to water as 9.5:0.5, 9:1, 8.5:1.5, and 8:2, respectively, were characterized using creaming index analysis, dynamic light scattering and zeta potential measurements, rheological analysis, laser scanning confocal microscopy and polarized optical microscopy measurements, interfacial tension and interfacial film rheology measurements. A significant enhancement in heat sink and heat transfer coefficients of the emulsified fuel compared to pure JP-10 is observed within the temperature range from 100 to 225 °C. Simultaneous enhancements in drag reduction rate and heat transfer coefficient for the emulsified fuel in a distributed flow calorimeter can reach 19.5 % and 6.09 %, respectively. Emulsified fuels show great prospects in improving the stable and highly efficient operation of advanced aircraft.