CALCULATORS / PROCESS AND CHEMICAL ENGINEERING ESTIMATES

Process batch-heating energy calculator

Constant net power and uniform batch heat capacity; losses omitted.

chemistry-batch-heating.napkin / editable

SCENARIO COMPARISON

Compare the numbers.

This source describes an analytical model. Its quantities and checks are the view.

Scenario	energykJ	durations
	600	600
	480	480

All calculated quantities are listed with the inputs. Switch to Source to inspect the equations.

SCENARIOS / CALCULATED VALUESSAME SOURCE

Change an input to see the consequences.

batch heat time budget600.00 s✓ passes

BASELINE INPUTS

mass10 kgheatCapacity2000 J/(kg*K)rise30 Kpower1000 W

CALCULATED

energy600 kJ

duration600 s

Edits change the baseline source.

THE SOURCE

Edits below update the same model.

# Process batch-heating energy
# Scope: Constant net power and uniform batch heat capacity; losses omitted.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

mass = 10 kg
heatCapacity = 2000 J/(kg*K)
rise = 30 K
power = 1000 W

energy := mass*heatCapacity*rise [kJ]
duration := energy/power [s]

check batch heat time budget: duration <= 900 s

scenario alternative: mass = 8 kg

Calculated from your source · not saved

Baseline · Baseline

batch heat time budget600.00 s ✓ passes

alternative · alternative

batch heat time budget480.00 s ✓ passes

Illustrative first-order example. Checks are editable requirements, not design standards. The broader topic may require additional equations, data, and validation.

Formula and units

This example uses the following equations. Input names and units match the editable source above.

energy: energy = mass*heatCapacity*rise [kJ]
duration: duration = energy/power [s]

Original worked example

These are the baseline values in the downloadable source. Edits above let you test your own values.

Given

mass: 10 kg
heat capacity: 2000 J/(kg*K)
rise: 30 K
power: 1000 W

Calculated

energy: 600 kJ
duration: 600 s

Assumptions and limits

Constant net power and uniform batch heat capacity; losses omitted.

The requirement checks use the limits written in this example. Passing a check does not establish that the model covers every load, material behavior, or operating condition in a real design.

Download this .napkin example ↓

Take it further with your agent

Napkin keeps the inputs, equations, checks and assumptions together in one study. Your agent sets it up; you change the numbers.

Try with Claude ↗

codex 'Use Napkin (https://napkin.engineering/mcp, or the local Napkin plugin) to build a study: Process batch-heating energy. Inputs: batch masses; heat capacities; temperature change; losses. Outputs: energy; heating-time estimate. Model scope: Specified chemistry and low-order mass/energy balances. Read napkin_capabilities and the current snapshot. Ask me for the values that matter, label assumptions with units, author .napkin source, validate it and apply it with napkin_source using the current revision, then open the study. Add checks for the limits I supply. Keep unsupported analyses explicit.'

Claude needs the Napkin connector; Codex needs the Napkin plugin. Set up your agent ↗

The broader study

The topic brief below describes the broader scope. The worked example above states the particular calculation it implements.

Inputs: batch masses, heat capacities, temperature change, losses
Outputs: energy, heating-time estimate
Modes: calculate, compare, sweep
Drawing: Process balance diagram

EXECUTABLE WORKED EXAMPLE · FIRST-ORDER MODEL · CHECK THE SCOPE & ASSUMPTIONS