Investigation into the Impact of n-Decane, Decalin, and Isoparaffinic Solvent on Elastomeric Sealing Materials

Abstract

One of the crucial aspects in the adoption of alternative fuels (e.g., GtL fuel) in aviation industry is to investigate their compatibility with elastomeric materials used in current gas turbine engines. This study employed stress relaxation technique to investigate the effects of three solvents, namely, decalin (cycloparaffin), n-decane (normal paraffin), and ShellSol T solvent (isoparaffins) on O-rings made from different materials. Results indicated that both fluorosilicone and fluorocarbon O-rings showed excellent compatibility with all 25 blends tested. The stress relaxation characteristic of nitrile O-ring was highly dependent on the composition of the solvents; the more decalin (n-decane) is in the blend, the better (worse) its sealing performance becomes. Effects of the three solvents presented in the tests indicated aromatics are not the only compounds that can swell nitrile O-ring. It is also important to notice that although decalin presents good O-ring swelling ability, it does not mean all cycloparaffins have the same property. n-decane also showed certain O-ring swelling ability but its main effect during the polymer-fuel interaction process is to extract materials out of nitrile O-ring. Isoparaffins do not participate in the O-ring swelling process. They only extract polymer materials; however, its extraction ability is relatively weaker than n-decane.

Bio‐Based Cycloalkanes: The Missing Link to High‐Performance Sustainable Jet Fuels

“…Aqueous phase hydrodeoxygenation was performed on the substituted diphenylmethane products over Pd/C and HZSM-5 (Scheme 35). After vacuum distillation, the expected dicyclohexylmethane (24) [309] was observed in the reaction mixture as the minor product (31.4 %), while the intramolecular cyclization product, perhydrofluorene (25), was obtained as the major product (68.6 %). The density of pure dicyclohexylmethane is 0.88 g mL À 1 ,while perhydrofluorene has a density of 0.96 g mL À 1 at 20°C.…”

“…Recent work has shown that cycloalkanes at concentrations above about 30 vol % in SPKs have swelling characteristics similar to conventional jet fuel. [24][25][26] This result has opened up the development of aromatic-free bio-based fuels with increased gravimetric heats of combustion and improved emission profiles. [27] Bio-based cycloalkanes represent the missing link to the production of full-performance and ultra-performance drop-in synthetic fuels for commercial and military jet aircraft.…”

Chemoselective Hydrogenation of Ring‐Strained Monoterpenes: A Route to High‐Performance Sustainable Aviation Fuels

“…[ 9,10 ] In addition, recent research has suggested that cycloalkanes can potentially be used to replace aromatic compounds in SAF blends, improving gravimetric NHOC and reducing particulate emissions, while maintaining the essential seal‐swelling properties exhibited by conventional jet fuels. [ 11–14 ]…”

Impact of aromatic species selection and micro and bulk properties of alternative fuels on atomisation

“…The importance of aromatic components in jet fuel pertain to their ability to aid in overall lubricity and seal swell (13)(14)(15)(16) . This is imperative to maintain the integrity of the aircraft's fuel system.…”