US 6,044,825 A · Low pressure gas vaporizer and method of operation

Abstract

A fuel vaporizer and method of fuel vaporization are described for use with a fuel such as propane, that is know to tend to liquefy at low temperatures and to vaporize at high temperatures. The vaporizer and method described pertain to a series of internal walls and cavities which promote heat-exchange and transfers heat from a fluid engine coolant to the fuel. The transfer of heat and vaporization of fluid occurs by virtue of movement of the fuel through a series of countercurrent passages created by the walls and cavities, with increasing cross-sectional dimensions in the passages to accomodate the expansion of fuel from the liquid to the gaseous state. The heat is transferred by conduction across a metallic interface which forms part of the vaporizer and which separates the fuel from the coolant.

Claims33

Dependent claims

A fuel vaporizer for use with a fuel which tends to liquefy at low temperatures and to vaporize at high temperatures, said vaporizer comprising:

heat-exchange means adapted to transfer heat from a fluid engine coolant to said fuel;
and
an interface which forms part of said vaporizer and which separates said fuel from said coolant, said heat being transferred by conduction across said interface, said interface comprising a series of successively connected passages intermediate a starting point where said fuel enters said vaporizer and an end point where said fuel exits said vaporizer, each of said successively connected passages, commencing with a passage most proximate said starting point, being of lesser cross-sectional area than an immediately adjacent successively connected passageway progressing in a direction toward said endpoint, to thereby provide successively increasing cross-sectional area to accommodate said fuel as it changes state from mostly liquid at said starting point to mostly gaseous by said end point.

In a fuel vaporizer for use with a fuel that tends to liquefy at low temperatures and to vaporize at high temperatures, said vaporizer having heat-exchange means adapted to transfer heat from a fluid engine coolant to said fuel, wherein heat is transferred by conduction across a metallic interface which forms part of said vaporizer and which separates said fuel from said coolant, wherein:

said vaporizer defines for said fuel a path along which said fuel travels while heat transfer takes place, said path including, in the order encountered by said fuel:
a chamber for receiving said fuel,
a single, sinuous passage adjacent said chamber but substantially separated therefrom by a wall which defines a plurality of small-diameter apertures through which fuel in said chamber can be sprayed against a wall of said passage, said passage having one blind end, and having another end toward which said fuel travels and at which said passage branches into two portions through which it communicates with,
a pair of sinuous passages generally parallel with each other and with said single sinuous passage, but disposed such that fuel contained therein travels generally in the opposite direction from fuel travel in said single sinuous passage, the cross-sectional area of the combination of said pair of sinuous passages being greater than that of said single sinuous passage, so as to permit expansion of the volume of said fuel as it gradually vaporizes due to said heat input, said pair of sinuous passages at the downstream end thereof communicating with the ends of
a triplicity of sinuous passages generally parallel with each other and with said pair of sinuous passages, but disposed such that fuel contained therein travels generally in the opposite direction from fuel travel in said pair of sinuous passages, the crosssectional area of the combination of said triplicity of sinuous passages being greater than that of said pair of sinuous passages, so as to permit further expansion of the volume of said fuel as it continues to vaporize due to said heat input.

2 more elements

A fuel vaporizer for use with a fuel, such as propane, that tends to liquefy at low temperatures and to vaporize at high temperatures, said vaporizer having a body comprising:

means defining a first path for the flow of engine coolant therethrough,
means defining a second path for the flow of fluid fuel therethrough,
means defining a heat-exchanger through which heat can be transferred from said coolant to said fuel by conduction across a metallic interface which forms part of said vaporizer and which separates said fuel from said coolant,
said second path for said flow of fuel including, in the order encountered by said fuel:
chamber for receiving said fuel,
a single, sinuous passage adjacent to said chamber but substantially separated therefrom by a wall which defines a plurality of small-diameter apertures through which fuel in said chamber can be sprayed against a wall of said passage, said passage having, one blind end, and having another end toward which said fuel travels and at which said passage branches into two portions through which it communicates with,
a pair of sinuous passages generally parallel with each other and with said single sinuous passage, but disposed such that fuel contained therein travels generally in the opposite direction from fuel travel in said single sinuous passage, the cross-sectional area of the combination of said pair of sinuous passages being greater than that of said single sinuous passage, so as to permit expansion of the volume of said fuel as it gradually vaporizes due to said heat input, said pair of sinuous passages at the downstream end thereof communicating with the ends of a triplicity of sinuous passages generally parallel with each other and with said pair of sinuous passages, but disposed such that fuel contained therein travels generally in the opposite direction from fuel travel in said pair of sinuous passages, the cross-sectional area of the combination of said triplicity of sinuous passages being greater than that of said pair of sinuous passages, so as to permit further expansion of the volume of said fuel as it continues to vaporize due to said heat input.

4 more elements

A method of vaporizing a fuel that tends to liquefy at low temperatures and to vaporize at high temperatures, utilizing a vaporizer having heat-exchange means adapted to transfer heat from a fluid engine coolant to the fuel, wherein heat is transferred by conduction across a metallic interface which forms part of said vaporizer and which separates said fuel from said coolant, the method comprising the steps:

passing said fuel into a chamber defined by said vaporizer,
then passing, said fuel into a single, sinuous passage adjacent to said chamber but substantially separated therefrom by a wall which defines a plurality of small-diameter apertures, by spraying said fuel through said apertures against a wall of said single passage,
then passing said fuel into a pair of sinuous passages generally parallel with each other and with said single sinuous passage, whereby said fuel travels generally in the opposite direction from fuel travel in said single sinuous passage, the cross-sectional area of the combination of said pair of sinuous passages being greater than that of said single sinuous passage, so as to permit expansion of the volume of said fuel as it gradually vaporizes due to said heat input,
then passing said fuel into a triplicity of passages generally parallel with each other and with said pair of sinuous passages, but disposed such that fuel contained therein travels generally in the opposite direction from fuel travel in said pair of sinuous passages, the cross-sectional area of the combination of said triplicity of sinuous passages being greater than that of said pair of sinuous passages, so as to permit further expansion of the volume of said fuel as it continues to vaporize due to said heat input.

1 more element

Dependencies are inferred from the claim text.

Low pressure gas vaporizer and method of operation

Life of this patent

Low pressure gas vaporizer and method of operation

Life of this patent

Abstract

Claims33