Entropyk/apps/web/public/docs/components/correlations-and-maps.md

Correlations & performance maps / Corrélations & cartes

Master inventory of every performance map and heat-transfer / pressure-drop correlation wired in Entropyk (as of 2026-07-17).
Inventaire de toutes les cartes et corrélations du code.

Sources principales :

• crates/components/src/compressor.rs — AHRI 540 + SST/SDT
• crates/components/src/screw_economizer_compressor.rs — polynômes 2D + presets
• crates/components/src/isentropic_compressor.rs — η_is + volumétrique
• crates/components/src/polynomials.rs — Polynomial1D / Polynomial2D
• crates/components/src/heat_exchanger/bphx_correlation.rs — formules h
• crates/components/src/heat_exchanger/correlation_registry.rs — catalogue + domaines
• crates/components/src/heat_exchanger/eps_ntu.rs / lmtd.rs — HX génériques
• crates/components/src/heat_exchanger/two_phase_dp.rs — ΔP biphasique
• crates/components/src/fan.rs / pump.rs — courbes 1D

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EN

1. Compressors — performance maps

Component	Model ID	Formula (summary)	Inputs	Outputs	UI / JSON
IsentropicCompressor	Physics + η_is	h_dis = h_suc + (h_is−h_suc)/η_is ; emergent: ṁ = ρ·V_d·N·η_vol·z_flow	η_is, T guesses, V_d, N	ṁ, h_dis, W	η, emergent, displacement, speed
Compressor	AHRI 540 (model_type=Ahri540)	ṁ = M1·(1−(P_s/P_d)^{1/M2})·ρ·V·N/60 ; Ẇ_cool = M3+M4·PR+M5·T_s+M6·T_d (heating M7–M10)	M1…M10, V, N	ṁ, Ẇ	m1…m10, speed_rpm, displacement_m3
Compressor	SST/SDT poly (model_type=SstSdt)	ṁ = a00+a10·SST+a01·SDT+a11·SST·SDT ; same for Ẇ with pw_b**	bilinear coeffs	ṁ, Ẇ	mf_a**, pw_b** (CLI + UI)
ScrewEconomizerCompressor	Bilinear SST/SDT	ṁ_suc = z_flow·(a00+a10·SST+a01·SDT+a11·SST·SDT) ; same for Ẇ with b_ij ; eco fraction poly	presets + overrides	ṁ_suc, ṁ_eco, Ẇ	preset, mf_a**, pw_b**

Screw presets (CLI)

Preset	ṁ (a00,a10,a01,a11)	Power (b00,b10,b01,b11)	eco frac
bitzer_generic_200kw	1.35, 0.004, −0.0025, 1.2e−5	58000, 180, −280, 0.4	0.13
grasso_generic_200kw	1.30, 0.0035, −0.0022, 1e−5	60000, 190, −310, 0.45	0.11
(none)	1.2, 0.003, −0.002, 1e−5	55000, 200, −300, 0.5	0.12

Temps in polynomials: SST / SDT as used by the curve implementation (see source; typically °C in manufacturer fits — verify against Polynomial2D evaluation units in code).

Calibration Z on compressors

Factor	Effect
z_flow	scales ṁ
z_flow_eco	scales economizer ṁ (screw)
z_power	scales shaft power
z_etav	volumetric efficiency correction

Default all 1.0.

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2. Heat exchangers — heat transfer correlations

Correlation ID	Year	Purpose	Geometry	Wired in BPHX UI?
Longo2004	2004	Evap / cond HTC (plates)	Brazed plate	Yes (default)
Shah1979	1979	Condensation HTC	Tubes (also selectable)	Yes
Shah2021	2021	Plate condensation	Plates	Yes
Kandlikar1990	1990	Evaporation HTC	Tubes	Registry / BPHX enum
GungorWinterton1986	1986	Evaporation HTC	Tubes	Registry
Gnielinski1976	1976	Single-phase turbulent Nu	Tubes	Registry
DittusBoelter1930	1930	Single-phase Nu (simple)	Tubes	Registry
Ko2021	2021	Low-GWP plates	Plates	Registry
Friedel1979	1979	Two-phase ΔP	Tubes/plates	Registry (ΔP)

BPHX runtime path: correlation → h → UA ≈ h·A·z_ua → ε-NTU residuals (not a full multi-zone MB model).

Condenser / Evaporator / FloodedEvaporator: no plate correlation — lumped UA + phase-change ε-NTU:

ε = 1 − exp(−UA/C_sec)
Q = ε · C_sec · ΔT_driving

Generic HeatExchanger: ε-NTU or LMTD (arrangement-dependent).
Economizer (internal): LMTD-style two-stream.
MovingBoundaryHX: multi-zone research path (not default production).

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3. Pressure drop

Model	Formula / role	Components
Quadratic refrigerant	ΔP = k · ṁ · |ṁ|	Condenser, Evaporator (optional)
BPHX friction	ΔP = z_dp · 2·f·L·G²/(ρ·d_h) (implementation path)	BPHX
Friedel 1979	two-phase ΔP (registry)	selection stack
Pipe Darcy-style	f(L,D,ε,Re,ṁ)	Pipe
Valve orifice	ṁ = Kv·opening·√(2·ρ·ΔP)	EXV orifice, BypassValve

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4. Pumps & fans — 1D polynomials

y = c0 + c1·x + c2·x² + …     (Polynomial1D)

• Pump: head H(Q), efficiency η(Q); affinity laws for speed.
• Fan: static pressure / power vs flow and speed.

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5. Flow regularization (not a HTC correlation)

Smooth |ṁ|, activity α, duty blend — keeps Newton finite at zero flow. See flow-regularization.md.

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FR

Compresseurs

Composant	Modèle	Formule clé
Isentropic	Physique + η_is	h_dis isentropique corrigé ; ṁ = ρ V N η_vol
Compressor	AHRI 540 M1–M10	ṁ(P,ρ,V,N) ; Ẇ(PR, T)
Screw	Polynôme bilinéaire SST/SDT	ṁ, W = a00+a10·SST+a01·SDT+a11·SST·SDT

Presets vis : Bitzer / Grasso génériques 200 kW (coeffs dans CLI).

Échangeurs — corrélations h

Corrélation	Usage
Longo 2004	BPHX défaut évap/cond plaques
Shah 1979 / 2021	condensation (tubes / plaques)
Kandlikar, Gungor–Winterton	évaporation tubes (registre)
Gnielinski, Dittus–Boelter	monophasique
Ko 2021	plaques low-GWP
Friedel 1979	ΔP biphasique

Condenser / Evaporator / Flooded : UA global + ε-NTU (pas Longo).

Pompes / ventilateurs

Polynômes 1D Q–H / Q–η + lois d’affinité.

Calibration

Tous les Z par défaut 1.0 (pas de correction).