NOVELTY - The vaporizer (10) has an electrically-heated element (12) including an evaporation surface (24). A tube (25) i.e. insulative element, surrounds the electrically-heated element to define an annular flow space (27). The tube includes an entrance for a liquid hydrocarbon fuel to the annular flow space and an exit for vaporized hydrocarbon fuel from the annular flow space, where the radial dimension of an annulus (40) defines the annular flow space is lesser than 1.0 mm. A passage supplies a combustible gas to the vaporized hydrocarbon fuel to cause ignition of the vaporized hydrocarbon fuel.    USE - Electrically-heated contact vaporizer for vaporizing a liquid hydrocarbon fuel, for use in catalytic hydrocarbon reformer (claimed).    ADVANTAGE - The contact vaporizer vaporizes fuel in an efficient manner and eliminates the need for a separate igniter in a hydrocarbon reformer, thus providing contact vaporizer in an improved manner. A flow director is formed in the flow space and causes fuel and fuel vapor to follow a helical path through flow space, thus preventing channeling such that a longer contact path is defined for fuel against surface and fuel and fuel vapor are distributed evenly over surface, and hence preventing formation of undesirable hot spots. The fuel vapor exits contact vaporizer with a swirling motion, thus improving mixing with introduced air in a mixing chamber. The spiral pattern of the flow director is formed with a constant pitch or with a varied pitch, thus optimizing fuel vaporization. The tube is formed of an insulative material, thus minimizing the heat losses from the heated fuel. The outer tubular wall seals the vaporizer while minimizing parasitic heat transfer due to low mass structure.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a catalytic hydrocarbon reformer, comprising an electrically-heated contact vaporizer for vaporizing a liquid hydrocarbon fuel.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of an electrically-heated contact vaporizer.    Electrically-heated contact vaporizer (10)    Electrically-heated element (12)    Evaporation surface (24)    Tube (25)    Annular flow space (27)    Annulus (40)