Week 6 - Data analysis

Calculation of power output and Specific fuel consumption (SFC)

power_output = n*area*stroke_cycle/(1000)

where;

n= number of cylinders

area = area under PV diagram (obtained from data set)

stroke_cycle = revolutions per second/ 2

SFC = (fuel_consumption * 106 * stroke_cycle * 3600) / (power_output * 1000)

Program:

import math
import matplotlib.pyplot as plt
import numpy as np
from scipy.integrate import simps

#Compatibility check
fname = input("Enter the filename:")

if fname == 'engine_data.out':
print('file is valid')

else:
print('file is invalid')
exit()

def compatibility_check(a):
if 'CONVERGE' not in a:
print('Please provide converge output file to process')
exit()
else:
print('Compatibility check is successful')
pass

#try:
open('engine_data.out')

# Creating an empty array to store the values of Volume and pressure respectively
Volume = []
pressure = []

line_count = 1
for line in open('engine_data.out'):
if '#' not in line:
Volume.append(float(line.split()[7]))
pressure.append(float(line.split()[1]))
line_count = line_count + 1

#plotting p-v diagram
plt.plot(Volume, pressure, linewidth = 2, color = 'b')
plt.xlabel('Volume')
plt.ylabel('pressure')
plt.title("p-v diagram of engine")
plt.grid()
plt.show()

area = float(simps(pressure,Volume))
print('Area under the curve using Simpsons Rule :' +str(area) + ' units')
print('Work done by the engine : ' + str(area) + ' MJ')
area = area * 1e6
print('Work done by engine : ' + str(area) + ' J')

# Inputs
# Speed of an Engine
rpm = 1500
rps = 1500/60
stroke_cycle = rps/2
# Fuel consumption in micrograms per 1 stroke cycle
fuel_consumption = 20
# Engine specifications
# Number of cylinder
n = 1
# 4 stroke engine
# Calculation of power output and Specific fuel consumption
power_output = n*area*stroke_cycle/(1000)
print('power output from engine : ' + str(power_output) + 'KW')
SFC = (fuel_consumption*pow(10,-6)*stroke_cycle*3600)/(power_output*1000)
print('Specific Fuel consumption, SFC = ' + str(SFC) + ' (kg/hr)/KW')
print('t')

# Calculation of Area under PV diagram
Area = np.trapz(pressure,Volume)
print('Area under curve using trapezoidal rule : ' + str(Area) + 'units')
print('Work done by the engine : ' + str(Area) + ' MJ' )
Area = Area * 1e6
print('Work done by engine : ' + str(Area) + ' J')
power_output = n*Area*stroke_cycle/(1000)
print('power output from the engine : ' + str(power_output) + 'KW')
SFC = (fuel_consumption*pow(10,-6)*stroke_cycle*3600)/(power_output*1000)
print('Specific Fuel consumption, SFC = ' + str(SFC) + ' (kg/hr)/KW')
print('t')

# Transposing columns in to row matrix and converting them in to float type from string type
#transpose = np.transpose(data)
#float_f = transpose.astype(np.float)

# Array for header and their units
#parameters = ['Crank','Pressure','Maximum Pressure','Minimum Pressure','Mean Temperature','MaximumTemperature','Minimum Temperature','Volume','Mass','Density','Integrated HR','HRrate','Cp','Cv','gamma','Kinematic Viscosity','Dynamic Viscosity']

units = ['(DEG)','(Mpa)','(Mpa)','(Mpa)','(K)','(K)','(K)','pow(m,3)','(kg)','(kg/(pow(m,3)))','(J)','(J)','(J/time)'
,'(J/kgK)','(J/kgK)','','pow(m,2)/s','(Ns/pow(m,2)']

# Providing user choice of picking 2 parameters for plotting

print('Choose from following options and press enter key')

print('1 Crank n 2 Pressure n 3 Maximum Pressure n 4 Minimum Pressure n 5 Mean Temperature n 6 MaximumTemperature n 7 Minimum Temperature n 8 Volume n 9 Mass n 10 Density n 11 Integrated HR n 12 HR rate n 13 Cp n 14 Cv n 15 gamma n 16 Kinematic Viscosity n 17 Dynamic Viscosity')

X = int(input('Enter your choice on X-axis n'))
Y = int(input('Enter your choice on Y-axis n'))
n = X-1
m = Y-1
crank = []
max_pressure = []
min_pressure = []
mean_temp = []
max_temp = []
min_temp = []
mass = []
density = []
integra_HR = []
HRrate = []
Cp = []
Cv = []
gamma = []
Kinematic_viscosity = []
Dynamic_viscosity = []

line_count = 1
for line in open('engine_data.out'):
if '#' not in line:
crank.append(float(line.split()[0]))
max_pressure.append(float(line.split()[2]))
min_pressure.append(float(line.split()[3]))
mean_temp.append(float(line.split()[4]))
max_temp.append(float(line.split()[5]))
min_temp.append(float(line.split()[6]))
mass.append(float(line.split()[8]))
density.append(float(line.split()[9]))
integra_HR.append(float(line.split()[10]))
HRrate.append(float(line.split()[11]))
Cp.append(float(line.split()[12]))
Cv.append(float(line.split()[13]))
gamma.append(float(line.split()[14]))
Kinematic_viscosity.append(float(line.split()[15]))
Dynamic_viscosity.append(float(line.split()[16]))
line_count = line_count + 1
parameter = np.array([crank,pressure,max_pressure,min_pressure,mean_temp,max_temp,min_temp,Volume,mass,density,integra_HR,HRrate,Cp,Cv,gamma,Kinematic_viscosity,Dynamic_viscosity])
parameters = ['Crank','Pressure','Maximum Pressure','Minimum Pressure','Mean Temperature','MaximumTemperature','Minimum Temperature','Volume','Mass','Density','Integrated HR','HRrate','Cp','Cv','gamma','Kinematic Viscosity','Dynamic Viscosity']
units = ['(DEG)','(Mpa)','(Mpa)','(Mpa)','(K)','(K)','(K)','pow(m,3)','(kg)','(kg/(pow(m,3)))','(J)','(J)','(J/time)'
,'(J/kgK)','(J/kgK)','','pow(m,2)/s','(Ns/pow(m,2)']

plt.figure("User input plotting")
plt.plot(parameter[n],parameter[m],linewidth=3)
plt.title(' plot for ' + parameters[m]+ ' versus ' +parameters[n],color='k')
plt.xlabel(parameters[n] + ' ' +units[n])
plt.ylabel(parameters[m] + ' ' +units[m])
plt.grid()
plt.show()