com.synerset.hvacengine.process.drycooling.DryCoolingFromTemperature Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of hvac-engine Show documentation

HVAC|Engine is a comprehensive library for calculating moist air properties, including crucial thermodynamic processes such as heating, dry cooling, real cooling with condensate discharge, mixing single or multiple air streams, and more. Immutable, thread-safe, very accurate.

There is a newer version: 1.2.0

Show newest version

package com.synerset.hvacengine.process.drycooling;

import com.synerset.hvacengine.fluids.humidair.FlowOfHumidAir;
import com.synerset.hvacengine.fluids.humidair.HumidAir;
import com.synerset.hvacengine.fluids.humidair.HumidAirEquations;
import com.synerset.unitility.unitsystem.flows.MassFlow;
import com.synerset.unitility.unitsystem.thermodynamic.Power;
import com.synerset.unitility.unitsystem.thermodynamic.Temperature;

/**
 * Calculates outlet cooling power (heat of process) for dry cooling case based on target outlet temperature.
 * Target temperature must be lower than inlet flow temp for valid cooling case.
 * IMPORTANT: Inappropriate use of dry cooling will produce significant overestimation of outlet temperature or
 * underestimation of required cooling power!
 * Real cooling methodology is recommended to use as relatively accurate representation of real world cooling process.
 *
 * REFERENCE SOURCE: [1][2] [t2,oC] (42)(2.2) [6.12][37]
 *
 * @param inletAir          initial {@link FlowOfHumidAir}
 * @param outletTemperature target {@link Temperature}
 */
record DryCoolingFromTemperature(FlowOfHumidAir inletAir,
                                 Temperature outletTemperature) implements DryCoolingStrategy {

    @Override
    public DryAirCoolingResult applyDryCooling() {

        // Target temperature must be lower than inlet temperature for valid cooling case.
        if (outletTemperature.isEqualOrGreaterThan(inletAir.temperature())) {
            return new DryAirCoolingResult(inletAir, Power.ofWatts(0));
        }

        // If target temperature is below dew point temperature it is certain that this is no longer dry cooling
        if (outletTemperature.isLowerThan(inletAir.fluid().dewPointTemperature())) {
            return new DryAirCoolingResult(inletAir, Power.ofWatts(0));
        }

        double x_in = inletAir.humidityRatio().getInKilogramPerKilogram();
        double mda_in = inletAir.dryAirMassFlow().getInKilogramsPerSecond();
        double t_out = outletTemperature.getInCelsius();
        double p_in = inletAir.pressure().getInPascals();
        double i_in = inletAir.specificEnthalpy().getInKiloJoulesPerKiloGram();
        double i2 = HumidAirEquations.specificEnthalpy(t_out, x_in, p_in);
        double Q_heat = (mda_in * i2 - mda_in * i_in) * 1000d;
        Power requiredHeat = Power.ofWatts(Q_heat);

        HumidAir outletHumidAir = HumidAir.of(inletAir.pressure(), Temperature.ofCelsius(t_out), inletAir.humidityRatio());
        FlowOfHumidAir outletFlow = FlowOfHumidAir.ofDryAirMassFlow(outletHumidAir, MassFlow.ofKilogramsPerSecond(mda_in));

        return new DryAirCoolingResult(outletFlow, requiredHeat);

    }

}