Abstract: A heater includes a flow guide and electrical resistance heating elements. The flow guide defines a continuous geometric helicoid disposed about a longitudinal axis and defines perforations that extend in a longitudinal direction through a first longitudinal length of the geometric helicoid. The first longitudinal length is less than a full longitudinal length of the geometric helicoid. The electrical resistance heating elements extend through the perforations. For each electrical resistance heating element, a length of that electrical resistance heating element and a pitch of the geometric helicoid at a distal end of that electrical resistance heating element are such that the distal end of that electrical resistance heating element is a distance X from the geometric helicoid at the distal end of that electrical resistance heating element. The distance X is less than or equal to 40% of the pitch at the distal end of that electrical resistance heating element.

Abstract: A heater includes a flow guide and a plurality of electrical resistance heating elements. The flow guide defines a continuous geometric helicoid disposed about a longitudinal axis of the heater assembly. The flow guide defines a predetermined pattern of perforations that extend in a longitudinal direction through a first longitudinal length of the geometric helicoid, the longitudinal direction being parallel to the longitudinal axis. The plurality of electrical resistance heating elements extend through the perforations. At least one electrical resistance heating element of the plurality of electrical resistance heating elements has a first region with a first watt density and a second region with a second watt density. The second region is located farther in the longitudinal direction than the first region. The second watt density is less than the first watt density.

Abstract: A heater includes a flow guide and electrical resistance heating elements. The flow guide defines a continuous geometric helicoid disposed about a longitudinal axis and defines perforations that extend in a longitudinal direction through a first longitudinal length of the geometric helicoid. The first longitudinal length is less than a full longitudinal length of the geometric helicoid. The electrical resistance heating elements extend through the perforations. For each electrical resistance heating element, a length of that electrical resistance heating element and a pitch of the geometric helicoid at a distal end of that electrical resistance heating element are such that the distal end of that electrical resistance heating element is a distance X from the geometric helicoid at the distal end of that electrical resistance heating element. The distance X is less than or equal to 40% of the pitch at the distal end of that electrical resistance heating element.

Abstract: A heater includes a flow guide and a plurality of electrical resistance heating elements. The flow guide defines a continuous geometric helicoid disposed about a longitudinal axis of the heater assembly. The flow guide defines a predetermined pattern of perforations that extend in a longitudinal direction through a first longitudinal length of the geometric helicoid, the longitudinal direction being parallel to the longitudinal axis. The plurality of electrical resistance heating elements extend through the perforations. At least one electrical resistance heating element of the plurality of electrical resistance heating elements has a first region with a first watt density and a second region with a second watt density. The second region is located farther in the longitudinal direction than the first region. The second watt density is less than the first watt density.