Codes

function FNX(TH){
	return R*Math.sqrt(1-Math.pow((RR*Math.sin(TH)/R),2))-RR*Math.cos(TH);
}
function FNU(TH){
	return OM*RR*Math.sin(TH)*(1-RR*Math.cos(TH)/Math.sqrt(Math.pow(R,2)-Math.pow((RR*Math.sin(TH)),2)));
}

var R =2, RR = 0.5, D = 0.8, L = 8, MU = 1E-4, DELTA=0.001, RPM=1200,N=36,PI=3.1416;
var X=[],F=[];

document.writeln("R,RR,D,L=",R," ",RR," ",D," ",L);
document.writeln("
MU,DELTA,RPM,N,PI=",MU," ",DELTA," ",RPM," ",N," ",PI," ");


var OM=2*PI*RPM/60 , PERIOD=2*PI/OM, DT =PERIOD/(2*N);

var C1, W, F, a;
C1=MU*PI*D*L/(12*DELTA);
W=0;

for (I=0;I<=N ;I++ ){
	TH1=I*OM*DT;
	X.push(FNX(TH1));
	F.push(C1*FNU(TH1));
	
}
for (I=1;I<=N ;I++ ){
	W=W+0.5*(F[I]+F[I-1])*(X[I]-X[I-1]);
}
var POWER=W/(0.5*PERIOD);
document.write("
POWER=");
document.writeln(POWER);
document.write(" FT-LB/S");