Molten　salts　are　commonly　used　as　high　temperature　heat　transfer　and　storage　materials.　Compared　with　pure　molten　salt,　the　thermophysical　properties　of　molten　salt　nanofluids　are　improved.　This　study　focuses　on　the　heat　transfer　performance　analysis　of　molten　salt　based　SiO2　nanofluids　through　experiment　and　numerical　simulation　method.　The　results　indicate　that　the　Nusselt　number　(Nu)　in　bidirectional　twisted　tubes　is　20　%　higher　than　that　in　smooth　tube.　In　the　bidirectional　twisted　tubes,　the　field　synergy　angle　(θ)　in　the　middle　region　of　twisted　tube　B　(TT-B)　is　the　smallest,　and　the　heat　transfer　effect　is　the　best.　When　Re　=　48518,　Nu　=　312.3　of　TT-B,　and　the　f　=　0.033,　the　heat　transfer　effect　is　the　best,　and　the　highest　performance　evaluation　criteria　(PEC)　is　1.13.　There　is　an　inverse　relationship　between　heat　transfer　efficiency　and　heat　transfer　entropy　production.　The　heat　transfer　entropy　production　decrease　and　heat　transfer　efficiency　increases　with　the　increasing　of　the　number　of　reverse　twists.　When　the　Re　=　48518,　the　heat　transfer　efficiency　(Ε)　of　twisted　tube　D　(TT-D)　is　the　best,　but　its　pressure　drop　(Δp)　is　the　largest.　The　heat　transfer　correlation　of　nitrate/nitrite　molten　salt　nanofluids　is　fitted.　This　work　could　provide　basic　heat　transfer　data　of　molten　salt　nanofluids　in　twisted　tube　for　its　applications.　©　2024　Elsevier　Ltd