Week 2 Air standard Cycle

CODE :

import math 
import matplotlib.pyplot as plt
import numpy as np

def engine_kinematics(bore,stroke,con_rod,cr,start_crank,end_crank):
	
	a = stroke/2
	r = con_rod/a

	v_s = math.pi*(1/4)*pow(bore,2)*stroke
	v_c = v_s/(cr-1)

	s_c = math.radians(start_crank)
	e_c = math.radians(end_crank)

	num = 50
	dtheta = (e_c - s_c)/(num-1)
	v = []
	for i in range(0,num):
		theta = s_c + i*dtheta
		term1 = 0.5*(cr-1)
		term2 = r + 1 - math.cos(theta)
		term3 = pow(r,2) - pow(math.sin(theta),2)
		term3 = pow(term3,0.5)

		v.append((1+term1*(term2 -term3))*v_c)
	return v


p1 = 101325
t1 = 500
gamma = 1.4
t3 = 2300
bore = 0.1
stroke = 0.1
con_rod = 0.15
cr = 8

v_s = math.pi*pow(bore,2)*stroke*0.25
v_c = v_s/(cr-1)

v1 = v_s + v_c
v2 = v_c
p2 = p1*pow(v1,gamma)/pow(v2,gamma)

rhs = p1*v1/t1
t2 = p2*v2/rhs
v_compresssion = engine_kinematics(bore,stroke,con_rod,cr,180,0)

constant = p1*pow(v1,gamma)

p_copression = []

for v in v_compresssion:
	p_copression.append(constant/pow(v,gamma))


v3 = v2 
rhs = p2*v2/t2
p3 = rhs*t3/v3
v_expansion = engine_kinematics(bore,stroke,con_rod,cr,0,180)

constant = p3*pow(v3,gamma)
p_expansion = []

for v in v_expansion:
	p_expansion.append(constant/pow(v,gamma))


v4 = v1
p4 = p3*pow(v3,gamma)/pow(v4,gamma)

"""
rhs = p1*v1/t1
t4 = p4*v4/rhs
"""

a1 = (1/(v1/v2))
a2 = gamma-1
efficiency = (1-pow(a1,a2))*100

print(efficiency)

plt.xlabel('Volume')
plt.ylabel('Pressure')

plt.plot([v2,v3],[p2,p3])
plt.plot(v_compresssion,p_copression)
plt.plot(v_expansion,p_expansion)
plt.plot([v4,v1],[p4,p1])
plt.savefig('Otto_cycle.png')
plt.show()

OUTPUT: