Coupled Design of In-Plane Heat Spreading and Boundary-Tailored Nonuniform Discrete-Heater Geometry for Composite Electrothermal Ice-Protection Systems

Discrete heating and spatially varying convection jointly determine temperature distributions in composite electrothermal ice-protection structures. A two-dimensional transient multilayer model is used to examine the coupling between in-plane heat spreading and discrete heater geometry at fixed total-heat input. Matched-geometry material comparisons, analyses of coverage, strip count, and film thickness, and comparisons of nonuniform layouts under two flight-derived convective boundaries are used to evaluate interface temperature range, an edge thermal-mismatch metric, and thermal response. A 0.1-mm equivalent graphite-sheet spreader reduces the temperature difference between strips and gaps, with the effect depending on heater geometry and convective distribution. Increasing strip count produces different responses in temperature uniformity and the cumulative edge metric. In the 50-mm domain under the two flight boundaries, seven- and ten-strip spreader layouts reduce interface temperature range by 1.352–2.730 K and 2.607–2.930 K, respectively, relative to uniform layouts with the same strip count. For the ten-strip layout without the spreader, the comparison changes from −0.230 K to 1.327 K between the lower- and higher-Reynolds-number boundaries. For the lower-Reynolds-number ten-strip spreader case, domain extension from 50 to 100 mm reduces the benefit from 2.607 to 1.089 K, demonstrating strong dependence on lateral thermal connections.