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	   "source": [
       "# Chapter 16: Supercharging of IC Engines"
	   ]
	},
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 16.1: Power_supplied_to_supercharger.sce"
		   ]
		  },
  {
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"clc;funcprot(0);//EXAMPLE 16.1\n",
"// Initialisation of Variables\n",
"pwu=735;............//Power developed by naturally aspirated engine in kW\n",
"afru=12.8;.............//Air fuel ratio for naturally aspirated engine\n",
"bsfc=0.350;......//Brake specific fuel consumption in kg/kWh\n",
"metau=0.86;...........//Mechanical efficiency of naturally aspirated engine\n",
"pi=730;...........//Inlet pressure in mm of Hg absolute\n",
"tm=325;...........//Mixture temperature in Kelvin\n",
"pr=1.6;.............//Pressure ratio of supercharged engine\n",
"etaa=0.7;.............//Adiabatic efficiency of supercharged engine\n",
"metas=0.9;..............//Mechanical efficiency of supercharged engine\n",
"afrs=12.8;.............//Air fuel ratio for supercharged engine\n",
"rhohg=13600;.............//Density of mercury in kg/m^3\n",
"R=0.287;...................//Gas constant in kJ/kgK\n",
"ga=1.4;................//Degree of freedom for gas\n",
"cp=1.005;..................//Specific heat of the fuel\n",
"g=9.81;................//Acceleration due to gravity in m/s^2\n",
"//calculations\n",
"t2=tm*(pr)^((ga-1)/ga);..............//Ideal temperature for the supercharged engine\n",
"t2a=tm+(t2-tm)/etaa;................//Actual temperature for the supercharged engine\n",
"wa=cp*(t2a-tm);.....................//Work of the supercharger\n",
"wsup=cp*(t2a-tm)/metas;..............//Work required to drive the supercharger in kJ/kg of air\n",
"//When unsupercharged\n",
"p1=(pi/1000)*((g*rhohg)/1000);..............//Inlet pressure in kN/m^2\n",
"rhounsup=p1/(R*tm);\n",
"maunsup=(bsfc*pwu*afrs)/3600;...................//Air consumption in kg/s for unsupercharged engine\n",
"//When supercharged\n",
"rhosup=(pr*p1)/(R*t2a);\n",
"masup=maunsup*(rhosup/rhounsup);..................//Air consumption in kg/s\n",
"Psup=masup*wsup;...............//Power required to run the supercharger in kW\n",
"disp(Psup,'The Power required to run the supercharger (kW):')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 16.2: Engine_Capacity_and_Brake_Mean_effective_Pressure.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
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"clc;funcprot(0);//EXAMPLE 16.2\n",
"// Initialisation of Variables\n",
"p1=1.0132;..............//Mean pressure at sea level in bar\n",
"t1=283;................//Mean temperature at sea level in Kelvin\n",
"BP=260;....................//Brake Power output in kW\n",
"etaV=0.78;..................//Volumetric efficiency at sea level free air condition\n",
"sfc=0.247;............//Specific Fuel consumption in kg/kW.h\n",
"afr=17;...................//Air fuel ratio\n",
"N=1500;...................//Engine rpm\n",
"at=2700;.................//Altitude in mts\n",
"p2=0.72;................//Pressure in bar at the given altitude\n",
"Psup=0.08;.................//8% power of engine is taken by the supercharger\n",
"R=287;...................//Gas constant in J/kgK\n",
"t2=32+273;..............//Temperature in Kelvin at the given altitude\n",
"//calculations\n",
"mf=(sfc*BP)/60;.............//Fuel consumption in kg/min\n",
"ma = mf*afr;..................//Air consumption in ig/min\n",
"acps = ma/(N/2);............//Air consumption per stroke in kg\n",
"Vs=(acps*R*t1)/(etaV*p1*10^5);................//Engine capacity in m^3\n",
"disp(Vs,'The Engin Capacity in m^3:')\n",
"pmb=(BP*6)/(Vs*10*(N/2));........//Brake Mean Effective Pressure in bar\n",
"disp(pmb,'The Brake mean effective pressure is (bar) :')\n",
"gp=BP/(1-Psup);.................//Gross power produced by supercharged engine in kW\n",
"masup=ma*gp/BP;......................//Mass of air required for supercharged engine in kg\n",
"matc=masup/(N/2);..............//Mass of air taken per cycle\n",
"pressure=(matc*R*t2)/(etaV*10^5*Vs);\n",
"disp(pressure-p2,'The Increase of pressure required (in bar):')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 16.3: Increase_in_Brake_Power_due_to_supercharger.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
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"clc;funcprot(0);//EXAMPLE 16.3\n",
"// Initialisation of Variables\n",
"ec=3600*10^(-6);.............//Engine capacity in m^3\n",
"pw=13;...............//Power developed in kW per m^3 of free air induced per minute\n",
"etaV=0.82;............//Volumetric Efficiency\n",
"N=3000;................//Engine rpm\n",
"p1=1.0132;...........................//Initial Air pressure in bar\n",
"t1=298;........................//Initial Temperature in Kelvin\n",
"pr=1.8;.....................//Pressure ratio in rotary compressor\n",
"etaC=0.75;.................//Isentropic efficiency of compressor\n",
"etaM=0.8;....................//Mechanical efficiency\n",
"ga=1.4;.....................//Degree of freedom for the gas\n",
"td=4;.......................//The amount by which the temperature is kess than delivery temperature from compressor\n",
"R=287;......................//Gas constant in J/kg.K\n",
"cp=1.005;.....................//Specific heat capacity\n",
"//Calculations\n",
"Vs=(ec*N)/2;....................//Swept volume in m^3/min\n",
"Vu=Vs*etaV;....................//Unsupercharged volume induced per min\n",
"rcdp=pr*p1;........//Rotary compressor delivery pressure\n",
"t2=t1*(pr)^((ga-1)/ga);..............//Ideal temperature for the supercharged engine\n",
"t2a=t1+(t2-t1)/etaC;................//Actual temperature for the supercharged engine\n",
"ta=t2a-td;............................//Temperature of air at intake to the engine cylinder\n",
"V1=(rcdp*Vs*t1)/(p1*ta);.................//Equivalent volume at 1.0132 bar and 298 K\n",
"Vinc=V1-Vs;...........................//Increase in induced Volume of air in m^3/min\n",
"ipincai=pw*Vinc;.......................//Increase in IP from air induced in kW\n",
"ipinciip=((rcdp-p1)*10^5*Vs)/(60*1000);...........//Increase in IP due to increased induction pressure kW\n",
"ipinctot=ipincai+ipinciip;...............//Total increase in Input Power in kW\n",
"bpinc=ipinctot*etaM;....................//Increase in Brake Power of the engine in kW\n",
"ma=(rcdp*10^5*Vs)/(60*R*ta);...................//Mass of air delivered by the compressor kg/s\n",
"pc=(ma*cp*(t2a-t1))/etaM;....................//Power required by the compressor\n",
"bpincnet=bpinc-pc;..........................//Net Increase in BP\n",
"disp(bpincnet,'The Net increase in Brake Power in kW:')\n",
""
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 16.4: Engine_Capacity_and_Brake_Mean_effective_Pressure.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
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"source": [
"clc;funcprot(0);//EXAMPLE 16.4\n",
"// Initialisation of Variables\n",
"p1=1.0132;..............//Mean pressure at sea level in bar\n",
"t1=283;................//Mean temperature at sea level in Kelvin\n",
"BP=250;....................//Brake Power output in kW\n",
"etaV=0.78;..................//Volumetric efficiency at sea level free air condition\n",
"sfc=0.245;............//Specific Fuel consumption in kg/kW.h\n",
"afr=17;...................//Air fuel ratio\n",
"N=1500;...................//Engine rpm\n",
"at=2700;.................//Altitude in mts\n",
"p2=0.72;................//Pressure in bar at the given altitude\n",
"Psup=0.08;.................//8% power of engine is taken by the supercharger\n",
"R=287;...................//Gas constant in J/kgK\n",
"t2=32+273;..............//Temperature in Kelvin at the given altitude\n",
"//calculations\n",
"mf=(sfc*BP)/60;.............//Fuel consumption in kg/min\n",
"ma = mf*afr;..................//Air consumption in ig/min\n",
"acps = ma/(N/2);............//Air consumption per stroke in kg\n",
"Vs=(acps*R*t1)/(etaV*p1*10^5);................//Engine capacity in m^3\n",
"disp(Vs,'The Engin Capacity in m^3:')\n",
"pmb=(BP*6)/(Vs*10*(N/2));........//Brake Mean Effective Pressure in bar\n",
"disp(pmb,'The Brake mean effective pressure is (bar) :')\n",
"gp=BP/(1-Psup);.................//Gross power produced by supercharged engine in kW\n",
"masup=ma*gp/BP;......................//Mass of air required for supercharged engine in kg\n",
"matc=masup/(N/2);..............//Mass of air taken per cycle\n",
"pressure=(matc*R*t2)/(etaV*10^5*Vs);\n",
"disp(pressure-p2,'The Increase of pressure required (in bar):')"
   ]
   }
,
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		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 16.5: Compressor_run_by_supercharged_Engine.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
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"clc;funcprot(0);//EXAMPLE 16.5\n",
"// Initialisation of Variables\n",
"t1=298;.................//Temperature of the air while entering the compressor in Kelvin\n",
"qrej=1210;..............//Amount of heat rejected in cooler in kJ/min\n",
"t2=273+65;...............//Temperature of the air leaving the cooler in Kelvin\n",
"p2=1.75;.................//Pressure of the air leaving the cooler in bar\n",
"n=6;.....................//No of cylinders\n",
"d=0.1;...................//Bore of the cylinder in m\n",
"l=0.11;...................//Stroke of the cylinder in m\n",
"etaV=0.72;................//volumetric efficiency\n",
"N=2000;...............//Engine rpm\n",
"Tout=150;..................//Torque Output in Nm\n",
"etaM=0.8;..................//Mechanical efficiency\n",
"R=287;.......................//Gas constant for air in J/kgK\n",
"cp=1.005;...................//Specific capacity of air\n",
"//calculations\n",
"BP=(2*%pi*N*Tout)/(60*1000);...........//Brake power in kW\n",
"IP=BP/etaM;..........//Input Power in kW\n",
"Vc=(%pi/4)*d*d*l;...................//Cylinder Volume in m^3\n",
"pmi=(6*IP)/(n*Vc*(N/2)*10);................//Indicated mean effective pressure\n",
"disp(pmi,'The indicated mean effective pressure (in bar):')\n",
"Vs=Vc*6*(N/2);.........................//Engine Swept Volume in m^3/min\n",
"Vaa=Vs*etaV;..........................//Aspirated volume of air into engine in m^3/min\n",
"maa=(p2*10^5*Vaa)/(R*t2);..............//Aspirated air mass flow into the engine in kg/min\n",
"disp(maa,'The total aspirated air mass flow into the engine (in kg/min):')\n",
"t2a=((((BP/cp)/(qrej/(60*cp)))*t2)-t1)/(((BP/cp)/(qrej/(60*cp)))-1);\n",
"mc=((BP/cp)/(t2a-t1))*60;........................//Air flow into the compressor in kg/min\n",
"disp(mc,'Air flow into the compressor in kg/min:')\n",
"\n",
""
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