Regression rates and combustion characteristics of dicyclopentadiene based solid fuels with ball milled boron-PTFE additives

IF 5.8 2区工程技术 Q2 ENERGY & FUELS Combustion and Flame Pub Date : 2025-02-20 DOI:10.1016/j.combustflame.2025.114035

Dhruval N. Patel , Kyle E. Uhlenhake , Justin Kruse , Metin Örnek , Steven F. Son

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Abstract

Theoretically, boron is attractive as a fuel for air breathing applications; however, its ignition and combustion properties are inadequate for realizing its full potential. In this study, we investigated the effect of polytetrafluoroethylene (PTFE) addition on the combustion and reactivity of boron. We compared the effects of physical mixing and high energy ball milling boron-PTFE mixtures as a function of PTFE loading (0–30 wt.% PTFE). Lower exothermic peak temperatures and minimum ignition energies (MIE) were observed for ball milled boron-PTFE mixtures compared to physically mixed boron-PTFE mixtures, indicating higher reactivity. Conversely, ball milling boron without PTFE was shown to have a negligible or negative impact on exothermic peak temperatures and minimum ignition energy. To elucidate the effects of ball milling on boron-PTFE combustion in a fuel system, physical and ball milled mixtures of boron and boron-PTFE mixtures were added into dicyclopentadiene (DCPD). Fuel mixtures of 70 wt.% DCPD and 30 wt.% boron or boron-PTFE mixtures (PM-mixtures and BM-mixtures) were tested in a closed bomb calorimeter to determine heats of combustion and combustion efficiency and an opposed flow burner to determine regression rates and flame temperatures at varying oxidizer flow rates. Heats of combustion, combustion efficiencies and regression rates of DCPD based fuel mixtures are improved with ball milled additives compared to neat boron additives. Furthermore, increasing PTFE content in ball milled boron-PTFE additives enhanced the heats of combustion, combustion efficiencies and regression rates of DCPD based fuel mixtures. The enhanced combustion characteristics of ball milled boron-PTFE mixtures can be attributed to the reduced diffusion distances between intertwined boron and PTFE. These shorter diffusion distances elevate temperatures and increase the rate of boron oxide gasification. This improvement may render boron a more feasible fuel, especially in air-breathing applications.

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来源期刊

Combustion and Flame 工程技术-工程：化工

CiteScore

9.50

自引率

20.50%

发文量

631

审稿时长

3.8 months

期刊介绍： The mission of the journal is to publish high quality work from experimental, theoretical, and computational investigations on the fundamentals of combustion phenomena and closely allied matters. While submissions in all pertinent areas are welcomed, past and recent focus of the journal has been on: Development and validation of reaction kinetics, reduction of reaction mechanisms and modeling of combustion systems, including: Conventional, alternative and surrogate fuels; Pollutants; Particulate and aerosol formation and abatement; Heterogeneous processes. Experimental, theoretical, and computational studies of laminar and turbulent combustion phenomena, including: Premixed and non-premixed flames; Ignition and extinction phenomena; Flame propagation; Flame structure; Instabilities and swirl; Flame spread; Multi-phase reactants. Advances in diagnostic and computational methods in combustion, including: Measurement and simulation of scalar and vector properties; Novel techniques; State-of-the art applications. Fundamental investigations of combustion technologies and systems, including: Internal combustion engines; Gas turbines; Small- and large-scale stationary combustion and power generation; Catalytic combustion; Combustion synthesis; Combustion under extreme conditions; New concepts.