Nonlinear Heat — Temp-Dependent Conductivity (dim=40)
ADVANTAGES2 · dim 40SolvSRK wins. At the comparison noise level, SolvSRK beats the best baseline by at least 10 percentage points of survival, or by at least 0.05 balanced score when survival is tied. Use SolvSRK for this class of problem. All verdicts →
Same two-layer geometry as ir_two_layer_heat but with temperature-dependent diffusivity: alpha(T) = alpha_ref * (1 + beta*(T - T_ref)), beta=0.005 K^-1. The state-dependent system matrix makes this LRDE-ineligible. Tests the boundary of LRDE applicability: identical geometry, nonlinear physics.
Problem definition
Incropera & DeWitt, Fundamentals of Heat Transfer, 7th ed.; Mills, Heat Transfer, 2nd ed.
Canonical RHS excerpt from the registered callable used for this benchmark cell. Expand it to verify the state equations; it is not a standalone runnable fixture.
Show canonical RHS excerpt
def rhs(t: float, temp: np.ndarray) -> np.ndarray:
temp = np.clip(np.asarray(temp, dtype=float), 200.0, 3500.0)
d = np.zeros(n)
for i in range(n):
alpha_i = alpha_ref[i] * (1.0 + beta * (temp[i] - t_ref))
t_left = 400.0 if i == 0 else temp[i - 1]
t_right = 300.0 if i == n - 1 else temp[i + 1]
d[i] = alpha_i * (t_left - 2.0 * temp[i] + t_right) / dx2
return d- Parameters
- alpha_ref = [0.0001, 0.0001, 0.0001, 0.0001, 0.0001, 0.0001, …] [shape=(40,), min=1e-06, max=0.0001]
- beta = 0.005
- dx2 = 6.25e-08
- n = 40
- t_ref = 350
- Initial condition
- y(0) = [400, 397.435897436, 394.871794872, 392.307692308, 389.743589744, 387.179487179, …] [shape=(40,), min=300, max=400]
- Horizon
- t ∈ [0, 20]
Canonical RHS excerpt captured from the same registered callable used for the published benchmark. Frozen closure values are summarized below; helper imports and solver settings are intentionally omitted.
Fingerprint
Spread: high
Default noise: none
Recommendation snapshot
Clean best: SolvSRK
Noisy best: SolvSRK
Coverage
14 solver arms · clean + 5 noise levels
Ranked on survival, precision, and speed
Versions & freeze
Methodology →- Freeze
- 2026-08-13
- libsolvsrk
- 2.3.0
- SciPy
- 1.14
- SUNDIALS
- CVODE (bundled backend)
20 seeds/cell default · 14 arms · TRL 4–5 · simulation-lab validated · this page: Nonlinear Heat — Temp-Dependent Conductivity (dim=40) (nonlinear-heat-temp-dependent-conductivity-dim-40)
Governed SolvTune benchmark freeze; per-arm medians only. RHS definitions and raw trial rows are not published.
Self-reported by Resonix Labs · not independently verified
Results matrix
Pick an objective and a noise level to rank all arms on survival, median SCD, median nfev, and median wall time. Medians across seeds.
Objective
Best overall trade-off of survival, precision, and speed.
Noise level
| # | Solver | Survival | SCD | nfev | Wall | Score |
|---|---|---|---|---|---|---|
| 1 | SolvSRK | 100% | 11.5 | 1,619 | 65 ms | 0.892 |
| 2 | SciPy RadauSciPy | 100% | 10.8 | 800 | 48 ms | 0.877 |
| 3 | SciPy LSODASciPy | 100% | 8.9 | 1,544 | 58 ms | 0.831 |
| 4 | SciPy DOP853SciPy | 100% | 8.8 | 280,454 | 11.54 s | 0.828 |
| 5 | SciPy RK45SciPy | 100% | 8.7 | 315,746 | 13.24 s | 0.826 |
| 6 | Tsit5external | 100% | 8.6 | 325,068 | 42.00 s | 0.824 |
| 7 | CVODE BDFexternal | 100% | 8.6 | 416 | 24 ms | 0.823 |
| 8 | SciPy BDFSciPy | 100% | 8.2 | 473 | 34 ms | 0.814 |
| 9 | CVODE Adamsexternal | 100% | 8.2 | 1,575 | 71 ms | 0.814 |
| 10 | SciPy RK23SciPy | 100% | 7.9 | 178,409 | 7.87 s | 0.806 |
At Clean, best balanced arm is SolvSRK.
Values are medians across seeds, measured by Resonix Labs on Resonix hardware and not independently verified; nfev and wall are on reference lab hardware (indicative). Under injected noise only SolvSRK and the SciPy arms are run. How we measure accuracy → · Verification status →
Cite this page
Replace the access date. Pin the freeze ID and library versions when comparing against a later export. Cite it as what it is - a self-reported vendor benchmark, not an independently verified result. The note field says so; please keep it.
@misc{resonix_evidence_nonlinear_heat_temp_dependent_conductivity_dim_40_2026,
title = {Resonix Evidence Portal: Nonlinear Heat — Temp-Dependent Conductivity (dim=40)},
author = {{Resonix Labs (Canada) Inc.}},
year = {2026},
howpublished = {\url{https://resonixusa.com/evidence/problems/nonlinear-heat-temp-dependent-conductivity-dim-40}},
note = {Self-reported vendor benchmark; internally generated by Resonix Labs and not independently verified. Accessed YYYY-MM-DD. Freeze 2026-08-13; libsolvsrk 2.3.0; SciPy 1.14.}
}Related
TRL 4–5 · simulation-lab validated · 398 problems · 14 solver arms · clean + 5 noise levels
Freeze: 2026-08-13 · scipy 1.14 · libsolvsrk 2.3.0 · Methodology
Self-reported by Resonix Labs · not independently verified · Verification status