Entropyk/apps/web/public/docs/components/isentropic-compressor.md

IsentropicCompressor

Config type: "IsentropicCompressor"
Source: crates/components/src/isentropic_compressor.rs

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EN

Purpose & physical model

Vapor-compression compressor for cycle simulation. Two operating families:

Mode	When	Mass / pressure behaviour
Fixed-pressure (default)	emergent_pressure: false	Pins P_dis = P_sat(T_cond); mass continuity across suction/discharge
Emergent-pressure	emergent_pressure: true	Closes ṁ with a volumetric displacement law; P_dis floats from the condenser ↔ secondary balance

True isentropic path via CoolProp: (P,h)→s then (P,s)→h_is, corrected by isentropic efficiency:

h_dis = h_suc + (h_is − h_suc) / η_is,eff

Swept mass flow (emergent only):

ṁ_calc = ρ_suc · V_s · N · η_vol(P_dis/P_suc) · f_VSD,vol
ṁ      = σ · z_flow · ṁ_calc

Volumetric efficiency models:

Model	Formula
Constant	η_vol = const (default 1.0)
Clearance	η_vol = 1 + C − C · (P_dis/P_suc)^(1/n)

Optional VSD speed map (quadratic, identity default [1,0,0]):

f(r) = c0 + c1·r + c2·r² ,  r = N / N_ref ,  clamped ∈ [0.1, 1.2]
η_vol,eff = η_vol · f_vol(r) ;  η_is,eff = η_is · f_is(r)

Optional liquid injection desuperheat (no extra equation; φ from controls):

h_dis,eff = h_dis − φ_inj · (h_dis − h_f(P_dis)) ,  φ_inj ∈ [0, φ_max]

Design anchors t_cond_k, t_evap_k, superheat_k are used for fixed-pressure pins and as initial-condition helpers; in emergent mode the live suction (P,h) drives the isentropic path.

Residuals & n_equations()

n_equations = (2 if same_branch else 3) + (1 if slide_valve active else 0)

Row	Fixed-pressure	Emergent-pressure
r0	P_dis − P_sat(T_cond)	ṁ − σ·z_flow·ṁ_calc
r1	H_dis − h_dis	H_dis − h_dis,eff
r2	ṁ_dis − ṁ_suc (dropped if same-branch)	same
r3	—	(slide) T_sat(P_suc) − SST_target

Ports

Index	Role
0	suction (inlet)
1	discharge (outlet)

Edge-wired via set_system_context (CM1.3 ṁ/P/h triples). get_ports() may be empty.

Emergent pressure & actuators

• Requires displacement_m3 and speed_hz when emergent_pressure: true.
• Slide valve (slide_valve_sst_target_k / _c): free actuator σ ∈ [σ_min, 1] scales swept volume and holds SST.
• Liquid injection (liquid_injection: true): φ_inj on the actuator / control factor "injection"; closing equation from a user controls[] loop (e.g. max DGT), not hard-coded.

Calibration

Factor	Effect	Default
z_flow	scales swept ṁ (emergent r0)	1.0
actuator	slide σ or injection φ	–

measure_output / energy_transfers

• measure_output(Temperature) → discharge gas temperature (DGT) for injection control.
• energy_transfers: (Q, W) = (0, −ṁ·(h_dis,work − h_suc)) — adiabatic; shaft work negative. With liquid injection, work uses un-desuperheated compression enthalpy.

JSON parameters

Key	Meaning	Unit	Default
isentropic_efficiency	η_is	–	0.75
t_cond_k	condensing sat. T (fixed pin / design)	K	323.15
t_evap_k	evaporating sat. T (design)	K	275.15
superheat_k	suction superheat design	K	5.0
fluid	refrigerant	–	primary
emergent_pressure	enable displacement closure	bool	false
displacement_m3	swept volume V_s	m³/rev	0.0
speed_hz	rotational speed N	rev/s	0.0
volumetric_efficiency	constant η_vol	–	1.0
clearance	clearance ratio C (enables clearance model)	–	–
polytropic_n	re-expansion exponent	–	1.1
vsd_reference_speed_hz	VSD N_ref (enables map)	rev/s	–
vsd_volumetric_coeffs	[c0,c1,c2] η_vol map	–	[1,0,0]
vsd_isentropic_coeffs	[c0,c1,c2] η_is map	–	[1,0,0]
slide_valve_sst_target_k / _c	slide SST setpoint	K / °C	–
liquid_injection	enable injection desuperheat	bool	false
slide_position_init / min / max	free-actuator bounds	–	1.0 / 0.1 / 1.0

Notes

Preferred cycle compressor for physics-based machines. For manufacturer AHRI maps use "Compressor"; for economized screws use "ScrewEconomizerCompressor".

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FR

But & modèle physique

Compresseur à compression de vapeur. Deux familles de fonctionnement :

Mode	Quand	Comportement
Pression fixée (défaut)	emergent_pressure: false	Impose P_dis = P_sat(T_cond) ; continuité de masse
Pression émergente	emergent_pressure: true	Ferme ṁ par une loi volumétrique ; P_dis flotte via le condenseur

Chemin isentropique CoolProp + rendement :

h_dis = h_suc + (h_is − h_suc) / η_is,eff

Débit balayé (émergent) :

ṁ_calc = ρ_suc · V_s · N · η_vol(P_dis/P_suc) · f_VSD,vol
ṁ      = σ · z_flow · ṁ_calc

Modèles de rendement volumétrique : constant, ou volume mort η_vol = 1 + C − C·Pr^(1/n).
Carte VSD optionnelle (quadratique, identité [1,0,0]).
Injection liquide optionnelle : h_dis,eff = h_dis − φ_inj·(h_dis − h_f(P_dis)) (pas d'équation interne).

Résiduels & n_equations()

n_equations = (2 si même branche sinon 3) + (1 si tiroir actif)

Ligne	Pression fixée	Pression émergente
r0	P_dis − P_sat(T_cond)	ṁ − σ·z_flow·ṁ_calc
r1	H_dis − h_dis	H_dis − h_dis,eff
r2	ṁ_dis − ṁ_suc (supprimée si même branche)	idem
r3	—	(tiroir) T_sat(P_suc) − SST_cible

Ports

Index	Rôle
0	aspiration (entrée)
1	refoulement (sortie)

Câblage par arêtes (set_system_context, triples ṁ/P/h CM1.3).

Pression émergente & actionneurs

• displacement_m3 et speed_hz obligatoires en mode émergent.
• Tiroir (slide_valve_sst_target_k / _c) : actionneur libre σ pour tenir la SST.
• Injection liquide : φ_inj via boucle controls[] (ex. DGT max), facteur "injection".

Calibration

Facteur	Effet	Défaut
z_flow	échelle le débit balayé	1.0
actuator	position tiroir σ ou ratio d'injection φ	–

measure_output / energy_transfers

• Temperature → température des gaz de refoulement (DGT).
• (Q, W) = (0, −ṁ·(h_dis,work − h_suc)) — adiabatique ; travail sur le compresseur négatif.

Paramètres JSON

Clé	Signification	Unité	Défaut
isentropic_efficiency	η_is	–	0.75
t_cond_k	T sat. condensation (pin / design)	K	323.15
t_evap_k	T sat. évaporation (design)	K	275.15
superheat_k	surchauffe aspiration design	K	5.0
fluid	fluide frigorigène	–	primaire
emergent_pressure	active la fermeture volumétrique	bool	false
displacement_m3	cylindrée V_s	m³/tr	0.0
speed_hz	vitesse N	tr/s	0.0
volumetric_efficiency	η_vol constant	–	1.0
clearance	rapport volume mort C	–	–
polytropic_n	exposant de détente	–	1.1
vsd_reference_speed_hz	N_ref carte VSD	tr/s	–
vsd_volumetric_coeffs	[c0,c1,c2] carte η_vol	–	[1,0,0]
vsd_isentropic_coeffs	[c0,c1,c2] carte η_is	–	[1,0,0]
slide_valve_sst_target_k / _c	consigne SST tiroir	K / °C	–
liquid_injection	active la désurchauffe par injection	bool	false
slide_position_init / min / max	bornes actionneur libre	–	1.0 / 0.1 / 1.0

Notes

Compresseur de cycle préféré pour les machines physiques. Cartes fabricant AHRI → "Compressor" ; vis économisée → "ScrewEconomizerCompressor".