Tools · Fluids & Thermodynamics

Reaction Calorimetry & Thermal-Safety Model

Simulate the temperature and heat flow of a batch or semi-batch reactor, and screen its thermal-runaway risk if cooling fails.

Updated October 1, 2026

On this page

Prices, workflows, and method papers Open in the app

This tool models one liquid batch or semi-batch vessel from your reaction kinetics and heats of reaction: how temperature, concentrations, and heat flow evolve, and what would happen if cooling failed at any moment. It reports the standard thermal-safety screening numbers, with sensitivities and an optional Monte Carlo spread.

It is a screening model, not a certified safety assessment. It runs on CPU.

How it works

Modes: batch or semi_batch (one reactant fed at a constant rate), each adiabatic or jacketed (heat removed through the jacket: UA × (T − T_jacket)).
Model: a lumped energy balance on the reaction mass, with Arrhenius mass-action kinetics, per-reaction enthalpies, and a heat capacity (constant or a table against temperature). Volume and composition follow the feed exactly.
Cooling-failure scan: at many instants through the process, cooling and dosing are switched off and the mixture is followed adiabatically. From this come:
- MTSR, the maximum temperature of the synthesis reaction after a failure, and when the worst failure happens;
- ΔT_ad, the adiabatic temperature rise if the whole charge reacts;
- TMR_ad, the adiabatic time to maximum rate at the failure state (a conservative zero-order estimate);
- the heat still to be released (accumulation) at each instant.
Sensitivities of these results to every rate, activation energy, enthalpy, and the vessel parameters, and an optional Monte Carlo (up to 200 samples) from the uncertainties you give, reported as 5th, 50th, and 95th percentiles.

Inputs

kinetics: one row per irreversible reaction with its rate (k at a reference temperature with ea_j_mol, or a with ea_j_mol). The parameters table from Kinetic Parameter Fitter can be used as is, uncertainties included.
thermochemistry: each reaction's enthalpy (negative is exothermic).
vessel: volume, starting temperature, density, heat capacity, and for jacketed operation UA and the jacket temperature (fixed or ramped).
dosing (semi-batch): the feed, its volume, and dose time.
time_end and time_unit, and optional uncertainty.

Limits: 20 reactions, 30 species, and 200 Monte Carlo samples.

Outputs

File	Contents
`trajectory.csv`	Temperature, volume, conversion, and concentrations over time
`heat_flow.csv`	Heat released, removed, and accumulated over time
`cooling_failure.csv`	For each failure instant: the temperature reached, TMR_ad, and heat accumulation
`safety_summary.csv`	MTSR, ΔT_ad, TMR_ad, and peak temperature, with Monte Carlo percentiles
`sensitivity.csv`	How each result responds to each parameter

Not covered

Decomposition kinetics, gas evolution and pressure, multiphase systems, relief sizing, and regulatory criticality classes.

Run it from the API

Submit with Submit a job and the job_type below. Price it first with Estimate job reservation cost: submitting reserves that amount from your wallet, and the charge settles at the actual runtime.