HCNFs were produced by using an acetylene flame synthesis system (AFSS).

Thermal conductivity, density, specific heat, and viscosity of HCNFs were tested.

HCNFs enhanced class="mathmlsrc">title="View the MathML source" class="mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0894177716302783&_mathId=si1.gif&_user=111111111&_pii=S0894177716302783&_rdoc=1&_issn=08941777&md5=b45348f8f21417dce904d1ae60f23e37">class="imgLazyJSB inlineImage" height="19" width="22" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S0894177716302783-si1.gif">class="mathContainer hidden">class="mathCode">${\dot{Q}}_{\mathit{ex}}$ of up to 13.0% compared with water at optimal condition.

HCNFs increase P_p of the ACHE.

HCNFs maximum enhanced SEF of up to 11.7% compared with water.