How to simulate heat exchanger startup thermal lag
A hot ethanol-water process stream cooled against cold cooling water in a single counter-current exchanger. Solves the design steady state; switch to the Dynamic solve mode and step the hot feed temperature to see the classic HX thermal-lag response — the exchanger's metal wall smooths and delays the outlet-temperature change instead of tracking the feed step instantly.
- 1Open the ready-made model
Open the "Heat exchanger startup thermal lag" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
- 2Confirm the thermodynamics
This process is modeled with the NRTL property package over ethanol, water — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains HX1. Every block is a real, solvable unit op you can reconfigure on the canvas.
- 4Run the simulation
Click Run. The deterministic solver converges the material and energy balances (recycles included) and fills the live stream table — the AI never invents a number.
- 5Read the results and iterate
Inspect the converged streams, tweak a spec, and re-run — or ask the AI copilot to explain a result or diagnose a failed solve in plain English.
- Thermodynamics
- NRTL
- Components
- ethanol, water
- Unit operations
- HX1
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Heat exchanger startup thermal lag model simulate?
- A hot ethanol-water process stream cooled against cold cooling water in a single counter-current exchanger. Solves the design steady state; switch to the Dynamic solve mode and step the hot feed temperature to see the classic HX thermal-lag response — the exchanger's metal wall smooths and delays the outlet-temperature change instead of tracking the feed step instantly.
- Which thermodynamic method does it use?
- The NRTL property package, over ethanol, water — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains HX1. Every block is a real, solvable unit operation you can reconfigure, add to, or remove.
- Do I need to install software or buy a license?
- No. Heat exchanger startup thermal lag runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
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