/************************************************************************************
 * Copyright (C) 2008 by Politehnica University of Bucharest and Rutgers University
 * All rights reserved.
 * Refer to LICENSE for terms and conditions of use.
 ***********************************************************************************/
package vnsim.vehicular.emissions;
/**
 * Class for estimation of fuel consumption and emissions of Carbon Monoxide (CO),
 * Hydrocarbons (HC), Notrogen Oxides (NOx) and Carbon Dioxide (CO2)
 * 
 * @author Victor Gradinescu
 *
 */
public class EmissionsUtil {

	// average idle fuel consumption for light vehicles(LV) [mL/s]
	public static final double IDLE_FC = 1350.0 / 3600.0 ;  
	// average idle CO emission for light vehicles [g/s]
	public static final double IDLE_CO = 50.0 / 3600.0; 
	// average idle HC emission for light vehicles [g/s]
	public static final double IDLE_HC = 8.0 / 3600.0;
	// average idle NOx emission for light vehicles [g/s]
	public static final double IDLE_NOx = 2.0 / 3600.0;
	// average CO2 emission rate per unit of fuel consumed (LV) [g/mL]
	public static final double CO2_RATE = 2.5;
	// efficiency parameter (in relation to the energy of the engine)
	// fuel [mL/kJ], emissions [g/kJ]
	public static final double beta1F = 0.0900;
	public static final double beta1CO = 0.0150;
	public static final double beta1HC = 0;
	public static final double beta1NOx = 0.0010;
	// efficiency parameter (in relation to the product of inertia energy and acceleration)
	// only for positive acceleration
	// fuel [mL/kJ], emissions [g/kJ]
	public static final double beta2F = 0.0300;
	public static final double beta2CO = 0.0250;
	public static final double beta2HC = 0.0004;
	public static final double beta2NOx = 0.0002;
	
	// average vehicle mass [kg]
	public static final double Mv = 1400;
	//Tyre rolling resistance factor
	public static final double ROLLRESCOEF = 0.06;//0.1;
	//Aero. drag coef (wind factor 1.2)
	public static final double AIRRESCOEF = 0.3;//0.54;
	//frontal vehicle area [m^2]
	public static final double FRONTAL_AREA = 2.1;
	//air density [kg/m^3]
	public static final double AIRDENSITY = 1.29;
	
	public static final double g = 9.81; // [m/s^2]
	
	static double rollresforce = 500;//ROLLRESCOEF * Mv * g;  

	static double airDragForceCoef =  0.5 * AIRRESCOEF * FRONTAL_AREA * AIRDENSITY;  
	
	// value of fuel consumed during the specified time interval [mL]
	public static EmissionsResults estimateFuelConsumption(double speed, double acceleration, double seconds){
		double v = speed / 3.6; // [m/s] 
		double a = acceleration / (3.6 * 3600); // [m/s^2] 
		double dt = seconds;
		double fc, co, hc, nox;
//		System.out.println("v = "+v+"\na = "+a);
		double airDragForce = airDragForceCoef * v * v;  
		// total tractive force Rt
		double Rt = Mv * a + rollresforce + airDragForce;
		Rt /= 1000;
//		System.out.println(Rt + " " + airDragForce + " " +rollresforce);
		
		if (Rt <= 0){
			fc = IDLE_FC * dt;
			co = IDLE_CO * dt;
			hc = IDLE_HC  * dt;
			nox = IDLE_NOx * dt;
		}else{
			double term3 = 0;
			if (a  > 0)
				term3 = Mv * a * a * v / 1000;
			
			fc = (IDLE_FC + beta1F * Rt * v + beta2F * term3) * dt;
			co = (IDLE_CO + beta1CO * Rt * v + beta2CO * term3) * dt;
			hc = (IDLE_HC + beta1HC * Rt * v + beta2HC * term3) * dt;
			nox = (IDLE_NOx + beta1NOx * Rt * v + beta2NOx * term3) * dt;
		}
		return new EmissionsResults(fc, co, CO2_RATE * fc, hc, nox);
	}
	
	public static void main(String args[]){
		double dt = 1;
		double v[] = {70, 70, 70, 69, 66, 62, 56, 49, 38, 27, 15, 6, 0, 0, 2, 7, 16, 25, 35, 44, 53, 60, 65, 68, 70, 70, 70, 70, 70, 70};
		double a[] = {0, 0, 0, -0.5, -1, -1.5, -2, -2.5, -3, -3.4, -3.2, -2.1, -0.3, 0, 1, 2, 2.6, 3, 2.8, 2.6, 2.1, 1.6, 1.1, 0.7, 0.3, 0, 0, 0, 0, 0};
		for (int i = 0; i < 30; i++){
			EmissionsResults er = estimateFuelConsumption(v[i], a[i]* (3.6 * 3600),dt);
			System.out.println(i+" "+ er.fc * (3600.0 / dt) / 1000);
		}
//		EmissionsResults er = estimateFuelConsumption(100, 0 * (3.6 * 3600),dt);
//		System.out.println(er.fc);
	}

}