Files
reactor/src/specificClass.js

457 lines
17 KiB
JavaScript

const { ASM3, ASM_CONSTANTS } = require('./reaction_modules/asm3_class.js');
const { create, all, isArray } = require('mathjs');
const { assertNoNaN } = require('./utils.js');
const { childRegistrationUtils, logger, MeasurementContainer } = require('generalFunctions');
const EventEmitter = require('events');
const mathConfig = {
matrix: 'Array' // use Array as the matrix type
};
const math = create(all, mathConfig);
const BC_PADDING = 2;
const DEBUG = false;
const DAY2MS = 1000 * 60 * 60 * 24;
class Reactor {
/**
* Reactor base class.
* @param {object} config - Configuration object containing reactor parameters.
*/
constructor(config) {
this.config = config;
// EVOLV stuff
this.logger = new logger(this.config.general.logging.enabled, this.config.general.logging.logLevel, config.general.name);
this.emitter = new EventEmitter();
this.measurements = new MeasurementContainer();
this.childRegistrationUtils = new childRegistrationUtils(this); // Child registration utility
this.upstreamReactor = null;
this.downstreamReactor = null;
this.returnPump = null;
this.asm = new ASM3();
this.volume = config.volume; // fluid volume reactor [m3]
this.Fs = [0]; // fluid debits per inlet [m3 d-1]
this.Cs_in = [Array(ASM_CONSTANTS.NUM_SPECIES).fill(0)]; // composition influents
this.OTR = 0.0; // oxygen transfer rate [g O2 d-1 m-3]
this.temperature = 20; // temperature [C]
this.kla = config.kla; // if NaN, use externaly provided OTR [d-1]
this.currentTime = null; // milliseconds since epoch [ms]
this.timeStep = 1 / (24*60*60) * this.config.timeStep; // time step in seconds, converted to days.
this.speedUpFactor = 100; // speed up factor for simulation, 60 means 1 minute per simulated second
}
/**
* Setter for influent data.
* @param {object} input - Input object (msg) containing payload with inlet index, flow rate, and concentrations.
*/
set setInfluent(input) {
const i_in = input.payload.inlet;
if (this.Fs.length <= i_in) {
this.logger.debug(`Adding new inlet index ${i_in}.`);
this.Fs.push(0);
this.Cs_in.push(Array(ASM_CONSTANTS.NUM_SPECIES).fill(0));
this.setInfluent = input;
}
this.Fs[i_in] = input.payload.F;
this.Cs_in[i_in] = input.payload.C;
}
/**
* Setter for OTR (Oxygen Transfer Rate).
* @param {object} input - Input object (msg) containing payload with OTR value [g O2 d-1 m-3].
*/
set setOTR(input) {
this.OTR = input.payload;
}
/**
* Getter for effluent data.
* @returns {object} Effluent data object (msg).
*/
get getEffluent() {
const Cs = isArray(this.state.at(-1)) ? this.state.at(-1) : this.state;
const effluent = [{ topic: "Fluent", payload: { inlet: 0, F: math.sum(this.Fs), C: Cs }, timestamp: this.currentTime }];
if (this.returnPump) {
const recirculationFlow = this.returnPump.measurements.type("flow").variant("measured").position("atEquipment").getCurrentValue();
// constrain flow to prevent negatives
const F_main = Math.max(effluent[0].payload.F - recirculationFlow, 0);
const F_sidestream = effluent[0].payload.F < recirculationFlow ? effluent[0].payload.F : recirculationFlow;
effluent[0].payload.F = F_main;
effluent.push({ topic: "Fluent", payload: { inlet: 1, F: F_sidestream, C: Cs }, timestamp: this.currentTime });
}
return effluent;
}
/**
* Calculate the oxygen transfer rate (OTR) based on the dissolved oxygen concentration and temperature.
* @param {number} S_O - Dissolved oxygen concentration [g O2 m-3].
* @param {number} T - Temperature in Celsius, default to 20 C.
* @returns {number} - Calculated OTR [g O2 d-1 m-3].
*/
_calcOTR(S_O, T = 20.0) { // caculate the OTR using basic correlation, default to temperature: 20 C
const S_O_sat = 14.652 - 4.1022e-1 * T + 7.9910e-3 * T*T + 7.7774e-5 * T*T*T;
return this.kla * (S_O_sat - S_O);
}
/**
* Clip values in an array to zero.
* @param {Array} arr - Array of values to clip.
* @returns {Array} - New array with values clipped to zero.
*/
_arrayClip2Zero(arr) {
if (Array.isArray(arr)) {
return arr.map(x => this._arrayClip2Zero(x));
} else {
return arr < 0 ? 0 : arr;
}
}
registerChild(child, softwareType) {
if(!child) {
this.logger.error(`Invalid ${softwareType} child provided.`);
return;
}
switch (softwareType) {
case "measurement":
this.logger.debug(`Registering measurement child...`);
this._connectMeasurement(child);
break;
case "reactor":
this.logger.debug(`Registering reactor child...`);
this._connectReactor(child);
break;
case "machine":
this.logger.debug(`Registering machine child...`);
this._connectMachine(child);
break;
default:
this.logger.error(`Unrecognized softwareType: ${softwareType}`);
}
}
_connectMeasurement(measurementChild) {
const position = measurementChild.config.functionality.positionVsParent;
const measurementType = measurementChild.config.asset.type;
const eventName = `${measurementType}.measured.${position}`;
// Register event listener for measurement updates
measurementChild.measurements.emitter.on(eventName, (eventData) => {
this.logger.debug(`${position} ${measurementType} from ${eventData.childName}: ${eventData.value} ${eventData.unit}`);
// Store directly in parent's measurement container
this.measurements
.type(measurementType)
.variant("measured")
.position(position)
.value(eventData.value, eventData.timestamp, eventData.unit);
this._updateMeasurement(measurementType, eventData.value, position, eventData);
});
}
_connectReactor(reactorChild) {
if (reactorChild.config.functionality.positionVsParent != "upstream") {
this.logger.warn("Reactor children of reactors should always be upstream.");
}
if (math.abs(reactorChild.d_x - this.d_x) / this.d_x < 0.025) {
this.logger.warn("Significant grid sizing discrepancies between adjacent reactors! Change resolutions to match reactors grid step, or implement boundary value interpolation.");
}
// set upstream and downstream reactor variable in current and child nodes respectively for easy access
this.upstreamReactor = reactorChild;
reactorChild.downstreamReactor = this;
reactorChild.emitter.on("stateChange", (eventData) => {
this.logger.debug(`State change of upstream reactor detected.`);
this.updateState(eventData);
});
}
_connectMachine(machineChild) {
if (machineChild.config.functionality.positionVsParent == "downstream") {
machineChild.upstreamSource = this;
this.returnPump = machineChild;
}
}
_updateMeasurement(measurementType, value, position, context) {
this.logger.debug(`---------------------- updating ${measurementType} ------------------ `);
switch (measurementType) {
case "temperature":
if (position == "atEquipment") {
this.temperature = value;
}
break;
default:
this.logger.error(`Type '${measurementType}' not recognized for measured update.`);
return;
}
}
/**
* Update the reactor state based on the new time.
* @param {number} newTime - New time to update reactor state to, in milliseconds since epoch.
*/
updateState(newTime) { // expect update with timestamp
if (!this.currentTime) {
this.currentTime = newTime;
return;
}
if (this.upstreamReactor) {
// grab main effluent upstream reactor
this.setInfluent = this.upstreamReactor.getEffluent[0];
}
if (newTime === this.currentTime) {
// no update necessary
return;
}
const n_iter = Math.floor(this.speedUpFactor * (newTime-this.currentTime) / (this.timeStep*DAY2MS));
if (n_iter) {
let n = 0;
while (n < n_iter) {
this.tick(this.timeStep);
n += 1;
}
this.currentTime += n_iter * this.timeStep * DAY2MS / this.speedUpFactor;
this.emitter.emit("stateChange", this.currentTime);
}
}
}
class Reactor_CSTR extends Reactor {
/**
* Reactor_CSTR class for Continuous Stirred Tank Reactor.
* @param {object} config - Configuration object containing reactor parameters.
*/
constructor(config) {
super(config);
this.state = config.initialState;
}
/**
* Tick the reactor state using the forward Euler method.
* @param {number} time_step - Time step for the simulation [d].
* @returns {Array} - New reactor state.
*/
tick(time_step) { // tick reactor state using forward Euler method
const inflow = math.multiply(math.divide([this.Fs], this.volume), this.Cs_in)[0];
const outflow = math.multiply(-1 * math.sum(this.Fs) / this.volume, this.state);
const reaction = this.asm.compute_dC(this.state, this.temperature);
const transfer = Array(ASM_CONSTANTS.NUM_SPECIES).fill(0.0);
transfer[ASM_CONSTANTS.S_O_INDEX] = isNaN(this.kla) ? this.OTR : this._calcOTR(this.state[S_O_INDEX], this.temperature); // calculate OTR if kla is not NaN, otherwise use externaly calculated OTR
const dC_total = math.multiply(math.add(inflow, outflow, reaction, transfer), time_step)
this.state = this._arrayClip2Zero(math.add(this.state, dC_total)); // clip value element-wise to avoid negative concentrations
if(DEBUG){
assertNoNaN(dC_total, "change in state");
assertNoNaN(this.state, "new state");
}
return this.state;
}
}
class Reactor_PFR extends Reactor {
/**
* Reactor_PFR class for Plug Flow Reactor.
* @param {object} config - Configuration object containing reactor parameters.
*/
constructor(config) {
super(config);
this.length = config.length; // reactor length [m]
this.n_x = config.resolution_L; // number of slices
this.d_x = this.length / this.n_x;
this.A = this.volume / this.length; // crosssectional area [m2]
this.state = Array.from(Array(this.n_x), () => config.initialState.slice());
this.extendedState = Array.from(Array(this.n_x + 2*BC_PADDING), () => new Array(ASM_CONSTANTS.NUM_SPECIES).fill(0));
// initialise extended state
this.state.forEach((row, i) => this.extendedState[i+BC_PADDING] = row);
this.D = 0.0; // axial dispersion [m2 d-1]
this.D_op = this._makeDoperator();
assertNoNaN(this.D_op, "Derivative operator");
this.D2_op = this._makeD2operator();
assertNoNaN(this.D2_op, "Second derivative operator");
}
/**
* Setter for axial dispersion.
* @param {object} input - Input object (msg) containing payload with dispersion value [m2 d-1].
*/
set setDispersion(input) {
this.D = this._constrainDispersion(input.payload);
}
updateState(newTime) {
super.updateState(newTime);
// let Pe_local = this.d_x*math.sum(this.Fs)/(this.D*this.A)
this.D = this._constrainDispersion(this.D);
const Co_D = this.D*this.timeStep/(this.d_x*this.d_x);
// (Pe_local >= 2) && this.logger.warn(`Local Péclet number (${Pe_local}) is too high! Increase reactor resolution.`);
(Co_D >= 0.5) && this.logger.warn(`Courant number (${Co_D}) is too high! Reduce time step size.`);
if(DEBUG) {
console.log("Inlet state max " + math.max(this.state[0]))
console.log("Pe total " + this.length*math.sum(this.Fs)/(this.D*this.A));
console.log("Pe local " + Pe_local);
console.log("Co ad " + math.sum(this.Fs)*this.timeStep/(this.A*this.d_x));
console.log("Co D " + Co_D);
}
}
/**
* Tick the reactor state using explicit finite difference method.
* @param {number} time_step - Time step for the simulation [d].
* @returns {Array} - New reactor state.
*/
tick(time_step) {
this._applyBoundaryConditions();
const dispersion = math.multiply(this.D / (this.d_x*this.d_x), this.D2_op, this.extendedState);
const advection = math.multiply(-1 * math.sum(this.Fs) / (this.A*this.d_x), this.D_op, this.extendedState);
const reaction = this.extendedState.map((state_slice) => this.asm.compute_dC(state_slice, this.temperature));
const transfer = Array.from(Array(this.n_x+2*BC_PADDING), () => new Array(ASM_CONSTANTS.NUM_SPECIES).fill(0));
if (isNaN(this.kla)) { // calculate OTR if kla is not NaN, otherwise use externally calculated OTR
for (let i = BC_PADDING+1; i < BC_PADDING+this.n_x - 1; i++) {
transfer[i][ASM_CONSTANTS.S_O_INDEX] = this.OTR * this.n_x/(this.n_x-2);
}
} else {
for (let i = BC_PADDING+1; i < BC_PADDING+this.n_x - 1; i++) {
transfer[i][ASM_CONSTANTS.S_O_INDEX] = this._calcOTR(this.extendedState[i][ASM_CONSTANTS.S_O_INDEX], this.temperature);
}
}
const dC_total = math.multiply(math.add(dispersion, advection, reaction, transfer).slice(BC_PADDING, this.n_x+BC_PADDING), time_step);
const stateNew = math.add(this.state, dC_total);
if (DEBUG) {
assertNoNaN(dispersion, "dispersion");
assertNoNaN(advection, "advection");
assertNoNaN(reaction, "reaction");
assertNoNaN(dC_total, "change in state");
assertNoNaN(stateNew, "new state post BC");
}
this.state = this._arrayClip2Zero(stateNew);
this.state.forEach((row, i) => this.extendedState[i+BC_PADDING] = row);
return stateNew;
}
_updateMeasurement(measurementType, value, position, context) {
const grid_pos = Math.round(context.distance / this.config.length * this.n_x);
// naive approach for reconciling measurements and simulation
// could benefit from Kalman filter?
switch(measurementType) {
case "quantity (oxygen)":
this.state[grid_pos][ASM_CONSTANTS.S_O_INDEX] = value;
break;
case "quantity (ammonium)":
this.state[grid_pos][ASM_CONSTANTS.S_NH_INDEX] = value;
break;
case "quantity (nox)":
this.state[grid_pos][ASM_CONSTANTS.S_NO_INDEX] = value;
break;
default:
super._updateMeasurement(measurementType, value, position, context);
}
}
/**
* Apply boundary conditions to the reactor state.
* for inlet, apply generalised Danckwerts BC, if there is not flow, apply Neumann BC with no flux
* for outlet, apply regular Danckwerts BC (Neumann BC with no flux)
*/
_applyBoundaryConditions() {
// Upstream BC
if (this.upstreamReactor) {
// Open boundary
this.extendedState.splice(0, BC_PADDING, ...this.upstreamReactor.state.slice(-BC_PADDING));
} else {
if (math.sum(this.Fs) > 0) {
// Danckwerts BC
const BC_C_in = math.multiply(1 / math.sum(this.Fs), [this.Fs], this.Cs_in)[0];
const BC_dispersion_term = this.D*this.A/(math.sum(this.Fs)*this.d_x);
this.extendedState[BC_PADDING] = math.multiply(1/(1+BC_dispersion_term), math.add(BC_C_in, math.multiply(BC_dispersion_term, this.extendedState[BC_PADDING+1])));
// Numerical boundary condition
this.extendedState[BC_PADDING-1] = math.add(math.multiply(2, this.extendedState[BC_PADDING]), math.multiply(-2, this.extendedState[BC_PADDING+2]), this.extendedState[BC_PADDING+3]);
} else {
// Neumann BC (no flux)
this.extendedState.fill(this.extendedState[BC_PADDING], 0, BC_PADDING);
}
}
// Downstream BC
if (this.downstreamReactor) {
// Open boundary
this.extendedState.splice(this.n_x+BC_PADDING, BC_PADDING, ...this.downstreamReactor.state.slice(0, BC_PADDING));
} else {
// Neumann BC (no flux)
this.extendedState.fill(this.extendedState.at(-1-BC_PADDING), BC_PADDING+this.n_x);
}
}
/**
* Create finite difference first derivative operator.
* @returns {Array} - First derivative operator matrix.
*/
_makeDoperator() { // create gradient operator
const D_size = this.n_x+2*BC_PADDING;
const I = math.resize(math.diag(Array(D_size).fill(1/12), -2), [D_size, D_size]);
const A = math.resize(math.diag(Array(D_size).fill(-2/3), -1), [D_size, D_size]);
const B = math.resize(math.diag(Array(D_size).fill(2/3), 1), [D_size, D_size]);
const C = math.resize(math.diag(Array(D_size).fill(-1/12), 2), [D_size, D_size]);
const D = math.add(I, A, B, C);
// set by BCs elsewhere
D.forEach((row, i) => i < BC_PADDING || i >= this.n_x+BC_PADDING ? row.fill(0) : row);
return D;
}
/**
* Create central finite difference second derivative operator.
* @returns {Array} - Second derivative operator matrix.
*/
_makeD2operator() { // create the central second derivative operator
const D_size = this.n_x+2*BC_PADDING;
const I = math.diag(Array(D_size).fill(-2), 0);
const A = math.resize(math.diag(Array(D_size).fill(1), 1), [D_size, D_size]);
const B = math.resize(math.diag(Array(D_size).fill(1), -1), [D_size, D_size]);
const D2 = math.add(I, A, B);
// set by BCs elsewhere
D2.forEach((row, i) => i < BC_PADDING || i >= this.n_x+BC_PADDING ? row.fill(0) : row);
return D2;
}
_constrainDispersion(D) {
const Dmin = math.sum(this.Fs) * this.d_x / (1.999 * this.A);
if (D < Dmin) {
this.logger.warn(`Local Péclet number too high! Constraining given dispersion (${D}) to minimal value (${Dmin}).`);
return Dmin;
}
return D;
}
}
module.exports = { Reactor_CSTR, Reactor_PFR };