Link to a calculation Thermoprops addresses, for assistants and for people

A Worksheet's script lives in its address: a link opens it already solved, in the browser of whoever follows it. An assistant answering a thermodynamics question can write the script, link it, and the reader gets every state, value and chart, computed by CoolProp.

The address

https://luisbedoia.github.io/thermoprops/worksheet/?s=<script>

<script> is the script, encoded as encodeURIComponent does: spaces as %20, line breaks as %0A, + as %2B, # as %23.
The results are computed in the browser that opens the link (CoolProp in WebAssembly): the page's HTML does not hold them, so a reader without JavaScript sees only the script.
Nothing is sent anywhere: the script stays in the link and in the reader's browser.

The script

One statement per line; # starts a comment.

`fluid R134a`	The fluid of every state.
`units celsius`	How results are shown and bare numbers read: celsius (°C, kPa, kJ/kg), kelvin or imperial.
`reference ASHRAE`	Where h and s are measured from: ASHRAE as in the textbooks' refrigerant tables, IIR, NBP or DEF (CoolProp's default).
`1: T = 25 °C, P = 1 bar`	A state fixed by two properties.
`1: T = -10 °C, sat vapor`	A saturated state: sat liquid (x = 0) or sat vapor (x = 1).
`2: from 1, compressed to P = 1.2 MPa, eta = 80%`	A state reached from another by a process.
`3: P = P2, sat liquid`	A property of another state, by name.
`COP = (h1 - h4) / (h2 - h1)`	A value computed from states and other values: + - * / ^, sqrt, ln, exp, abs, min, max.
`print COP, T2 in °F`	The results to show; in picks the unit.
`draw 1 -> 2 -> 3 -> 4 -> 1`	The processes drawn on the chart.

Properties: T, P, h, s, x (quality), D (density), v, u, cp, cv, mu, k, Pr, Z, a (speed of sound), g; a state's are read as T2, h1, x4.
Processes: isentropic, compressed and expanded (with eta), throttled, isobaric, isothermal, isochoric, isenthalpic, polytropic (with n).
Units: °C, K, °F, °R, Pa, kPa, MPa, bar, atm, psi, kJ/kg, BTU/lb, kJ/(kg*K), kg/m^3, m^3/kg, kg/s, kg/h, kW, MW, W, hp, BTU/h, kJ, m/s, %. A number without a unit is read in the script's units.
Fluids: Air, Ammonia, Argon, CarbonDioxide, CarbonMonoxide, Ethanol, Helium, Hydrogen, IsoButane, Isopentane, Methane, n-Butane, n-Pentane, n-Propane, Nitrogen, Oxygen, R1234yf, R1234ze(E), R125, R134a, R143a, R152A, R22, R245fa, R32, R404A, R410A, R507A, Toluene, Water

Examples

Refrigeration cycle

# Vapor-compression refrigeration cycle
fluid R134a
units celsius
# h and s as in the textbooks' refrigerant tables
reference ASHRAE

# evaporator outlet
1: T = -10 °C, sat vapor
# compressor
2: from 1, compressed to P = 1.2 MPa, eta = 80%
# condenser outlet
3: P = P2, sat liquid
# expansion valve
4: from 3, throttled to P = P1

m = 0.05 kg/s
q_evap = h1 - h4
w_comp = h2 - h1
COP = q_evap / w_comp
Q_evap = m * q_evap

draw 1 -> 2 -> 3 -> 4 -> 1
print COP, Q_evap, T2

Open it solved

Rankine cycle

# Rankine cycle with a real turbine
fluid Water
units celsius

# condenser outlet
1: P = 10 kPa, sat liquid
# pump
2: from 1, isentropic to P = 8 MPa
# boiler outlet
3: P = P2, T = 480 °C
# turbine
4: from 3, expanded to P = P1, eta = 85%

w_pump = h2 - h1
w_turb = h3 - h4
q_in = h3 - h2
efficiency = (w_turb - w_pump) / q_in

draw 1 -> 2 -> 3 -> 4 -> 1
print efficiency in %, w_turb - w_pump, x4

Open it solved

The API, for agents

GET https://thermoprops-api.luisbedoia.workers.dev/solve?s=<script>

The same script, encoded the same way, solved on a server: the answer is JSON, with every state and its properties in the script's units, the computed values, the errors by line, and a short link that opens it solved in the Worksheet. A short link not opened for a year may expire; the address above never does.
For an agent that computes before answering, instead of interpolating tables. Free, with no key. Its manual, as plain text: https://thermoprops-api.luisbedoia.workers.dev/.
As an MCP server, for Claude, ChatGPT, Cursor or VS Code: add https://thermoprops-api.luisbedoia.workers.dev/mcp as a connector. Its tools: fluid_state, a state from two properties, and solve_worksheet, a whole script.

Other addresses

A fluid's tables (saturation by temperature and by pressure, superheated vapor) and diagrams, as HTML: https://luisbedoia.github.io/thermoprops/fluids/r134a/, in Spanish https://luisbedoia.github.io/thermoprops/es/fluidos/r134a/. All of them: fluids.
The State Explorer with a fluid chosen: https://luisbedoia.github.io/thermoprops/explorer/?fluid=R134a&units=celsius (units: celsius, kelvin or imperial).