Exergy Workflows

Purpose

Use exergy targeting when you need exergy metrics and exergetic graphs for an already solved thermal target.

Prerequisites

Run a compatible direct, indirect, or HPR thermal target first. Exergy is post-processing; it enriches an existing target family rather than solving a new thermal target from scratch.

Sample Case

Use pulp_mill.json for site-style exergy interpretation after a Total Site target.

Runnable Workflow

from OpenPinch import PinchProblem

problem = PinchProblem("pulp_mill.json")
problem.target.indirect_heat_integration()
exergy_target = problem.target.exergy(
    options={"base_target_type": "Total Site Target"},
)
summary = problem.summary_frame()

Expected Output

The selected thermal target is enriched with fields such as exergy_sources, exergy_sinks, ETE, exergy_req_min, and exergy_des_min.

Interpretation

Read the exergy result after the thermal picture is clear:

  1. confirm which target family was enriched

  2. inspect exergy_sources and exergy_sinks

  3. inspect exergy_req_min and exergy_des_min

  4. inspect exergetic graph families

Graph accessors are available after enrichment:

gcc_x = problem.plot.exergetic_grand_composite_curve()
nlp_x = problem.plot.exergetic_net_load_profiles()

Use zone_name=..., include_subzones=True, and period_id=... when the exergy scope needs to match a specific thermal solve.

Next Steps