MaximaLabs
Back to gallery
Reference model

Propane (R-290) heat pump heating a hydronic loop — a COOLPROP process flowsheet

A single-stage vapor-compression heat pump delivering heat to a space-heating water loop — the same cycle as a refrigerator, read from the hot end. Propane evaporates at 4.7 atm (273 K, an air- or ground-source evaporator at 0 °C), is compressed to 21 atm (condensing at 333 K, 60 °C) and condenses against the heating water in a real two-sided exchanger, so the delivered heat is a water stream you can read: 40 °C return warmed to 59 °C. A small makeup feed and purge close the refrigerant mass balance around the recycle, as in the refrigeration examples. Two numbers define the machine: 80 kW delivered for 28 kW of compressor work, a heating COP of 2.9 — 52% of the Carnot limit for this 60 K lift, which is where a real R-290 unit sits. Read COP on the flowsheet as the user variable cop_heating, or sweep the condensing pressure: from 18 to 27 atm the COP falls 3.2 → 2.6 as the lift grows, the trade every heat pump makes between water temperature and electricity. Honest scope: the compressor is a fixed isentropic efficiency, the condenser outlet is a specified subcooling, and there is no defrost, part-load or refrigerant-charge model. Below ~18 atm the specified 326 K condenser outlet sits above saturation and the cycle stops condensing — the sweep starts where the physics does.

1 views 0 forks

Makeup
MIX
COMP
Heating Water
hot
cold
hot
cold
Q out
COND
Valve
EVAP
Split
Purge
HOT Water
What this showcases
  • Rigorous COOLPROP thermodynamics, solved by the same engine every simulation runs on.
  • 6 unit operations modeled: MIX, COMP, COND, Valve, EVAP, Split.
  • Focus areas: Heat pump, Vapor-compression cycle, Recycle, Heating.
Specification
Thermodynamics
COOLPROP
Components
propane, water
Unit operations
MIXCOMPCONDValveEVAPSplit
Open in workspace

Opens in a new tab, loaded straight into the app — no setup.

Read the step-by-step guide
Python SDK

Reproduce this exact result from Python — the real client.get_example() → run_and_wait() path, not a mockup.

from flowsim.sdk import FlowSimClient

client = FlowSimClient()
example = client.get_example("propane-heat-pump-hydronic")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])

print(result["status"])              # "converged"
streams = client.streams(sim["id"])

Related models

Reference model (ChemSep)

Propane refrigeration cycle

A single-stage vapor-compression refrigeration loop: propane vapor is compressed, condensed to subcooled liquid, throttled through a valve, and superheated back to vapor in the evaporator before recycling — a small makeup feed and purge close the mass balance (inspired by ChemSep's Refrigeration_* reference cases).

Reference model (ChemSep)

Ammonia refrigeration cycle

A single-stage vapor-compression refrigeration loop using ammonia — the classic industrial (rather than HFC) refrigerant — condensed to subcooled liquid, throttled through a valve, and superheated back to vapor in the evaporator before recycling (inspired by ChemSep's Refrigeration_Ammonia-30C reference case).

Amarillo, Texas, USA

Helium liquefaction (Linde-Hampson cycle)

A Joule-Thomson liquefaction loop: helium is compressed, aftercooled, precooled well below its ~40-51 K JT-inversion temperature, then throttled through a valve into a flash drum that draws off liquid helium while the cold vapor recycles back to the compressor suction — the same JT-cycle physics as the platform's LNG/refrigeration loops, run on a fluid whose inversion curve makes precooling mandatory before the throttle can cool it at all.

Erlangen, Germany

LOHC hydrogen release (methylcyclohexane dehydrogenation)

A liquid organic hydrogen carrier (LOHC) power train: methylcyclohexane (MCH) is preheated and catalytically dehydrogenated (MCH → toluene + 3H2, endothermic, equilibrium-limited to ~90% single-pass conversion) to release hydrogen for downstream power generation. A flash drum separates the H₂-rich gas from the liquid; a distillation column then recovers the unreacted MCH overhead and recycles it to the reactor feed, closing a real tight liquid recycle loop, while spent toluene leaves the bottoms (to be re-hydrogenated back to MCH off-site, closing the supply-chain loop — out of scope for this dehydrogenation-side flowsheet). Screening-fidelity note: MCH and toluene are genuinely close-boiling (relative volatility ~1.4 under this thermo package at column conditions), so the recycle carries real toluene along with the recovered MCH rather than a sharp cut — a production column would use more stages to purify it further; this shows the recycle topology and its convergence, not an optimized column design.

Reference model

Recycle loop

A mixer/heater/splitter loop with a tear stream — exercises Wegstein recycle convergence.

Propylene splitter, Mont Belvieu, Texas, USA

Vapor re-compression propane/propylene splitter

Propylene/propane splitters have a notoriously low relative volatility (~1.1-1.15), so they run at high reflux and benefit from heat pumping: the overhead vapor is compressed and used to reboil the same column at a lower operating pressure (here 12 bar vs. a conventional ~20 bar), cutting the compressor shell cost (Christopher et al., Ind. Eng. Chem. Res. 56, 14557, 2017). The reboiler heat-integration loop itself is not modeled here (that would need a recycle-coupled duty match) — this shows the column plus the overhead compression/condensing train, a bounded simplification.

Stop fighting legacy software. Build your first flowsheet in 60 seconds.