In the previous post, we saw that for the heater element design with straight edges in replacement of the current eight-element ring-like design, it provides the similar Gaussian-like irradiance profiles, but with smaller power delivery efficiencies, as shown in the plot. This turned out to result in similar but less prominent thermal effects.

They only differ from the original baseline design by a source power rescaling, however, as shown in the plot, where we see the power-rescaled irradiance profiles for the straight edge designs are close to that for the ring design. The resulting temperature profiles and thermal distortions are shown in plot and plot. The thermal effects for the 16 straight-edge design with renormalized source power for instance are strikingly similar to that for the original ring design.

An alternative straightened heater element design has also been investigated with COMSOL FEA simulation. As shown in the attached, in this new design each heater element component is cut with multiple straight edges but remains connected, shown in the same colors (green and red). In the example, four straight edges are cut from each of the four heater components (4x4=16 edges in total). There is no spacing between the neighboring edges from the same element component, but the edges from different components are separated by 2mm, as can be seen in the attached. This new N-in-one straight edge design offers similar irradiance compared to that for the evenly-spaced N-sided regular polygon straight edge design with the same number of edges, as shown in the plot. It however has fewer heater components, four in this case, which makes it easier to implement in assembly and wiring, and less vulnerable to electrical and thermal shorts with their fewer heater element pins.