US Patent 11913736 Continuous helical baffle heat exchanger

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.