Chemical potential difference → Useful heat

Matrix context

D = disequilibrium row · C = coupling family column. A cell reads the state of the atlas for that pair.

D.05 × C.29 · Chemical potential difference × Thermochemicalfamily: ThermochemicalD.05 × C.07 · Chemical potential difference × Thermophotovoltaicfamily: ThermophotovoltaicD.05 × C.20 · Chemical potential difference × Photothermalfamily: Photothermal

Typed bounds on this route

Every limit the atlas holds for this route, as constraint records: reached through bounded_by claims on the route's own entities. Hard bounds (an upper bound or a formula) decide the thermodynamic-bound check above; benchmarks, constitutive relations and resource limits are listed and never decisive. No prose limit exists anywhere (pass 42).

• Visible-band fraction of thermal emission · formula-bound · hard, filtered out by its applicability
  η_vis ≤ ∫₃₈₀ⁿᵐ⁷⁸⁰ⁿᵐ B_λ(λ, T) dλ / σT⁴ — the share of a thermal emitter's radiated power that Planck's distribution places in the visible band at the emitter temperature
• Landsberg limit · formula-bound · hard, filtered out by its applicability
  η ≤ 1 − (4/3)(T_c/T_s) + (1/3)(T_c/T_s)⁴ for conversion of blackbody radiation at T_s with a sink at T_c; 93.3 % at 6000 K / 300 K

Steps

1. 01
   Chemical potential difference —drives→ Combustionestablishedclaim record

   chemical → thermal · loss to radiative

   • fuel, oxidiser and an ignition source; flame temperature 1500–2500 K

   gas · above ~700 K

   refs [1]
2. 02
   Combustion —produces→ Hot gasestablishedclaim record

   thermal → thermal

   refs [1]
3. 03
   Hot gas —drives→ Thermal emissionestablishedclaim record

   thermal → radiative

   • a flame or a heated emitter radiating

   refs [2] [1]
4. 04
   Thermal emission —produces→ Photonsestablishedclaim record

   radiative → radiative

   refs [3] [1]
5. 05
   Photons —drives→ Photothermal absorptionestablishedclaim record

   radiative → thermal

   refs [1]
6. 06
   Photothermal absorption —produces→ Heat flowestablishedclaim record

   thermal → thermal

   refs [1]
7. 07
   Heat flow —converts into→ Useful heatestablishedclaim record

   thermal → thermal

   • heat delivered at a temperature above the point of use

   refs [1]

Evidence for the complete composition · 0

No source on record for this exact composition. The sources below support the individual steps, not the route as a whole.

Evidence for the constituent relations · 3

1. [1]
   A. Bejan. Advanced Engineering Thermodynamics (4th ed.) (2016)

   Wiley · doi:10.1002/9781119245964 · crossref ✓ 2026-09-19 · record
2. [2]
   A. LaPotin, et al.. Thermophotovoltaic efficiency of 40% (2022)

   Nature 604, 287–291 · doi:10.1038/s41586-022-04473-y · crossref ✓ 2026-09-19 · record
3. [3]
   P. T. Landsberg, G. Tonge. Thermodynamic energy conversion efficiencies (1980)

   Journal of Applied Physics 51, R1–R20 · doi:10.1063/1.328187 · crossref ✓ 2026-09-19 · record