clear ;
addpath(genpath('.'))

% Data
r = 8 ; % [-]

% Units
bar = 1e5 ;    % [Pa]
cm  = 1/100 ;  % [m]
g   = 1/1000 ; % [kg]

% Ideal gas, air
gas.Rbar = 8.314 ;            % [J/(mol*K)]
gas.M    = 28.97 * g ;        % [kg/mol]
gas.R    = gas.Rbar / gas.M ; % [J/(kg*K)]

% Constant cp and cv
gas.k  = 1.4 ; % [-]
gas.cv = gas.R / ( gas.k - 1 ) ;
gas.cp = gas.k * gas.cv ;

% States
state1.T = 300 ;         % [K]
state1.p = 1.013 * bar ; % [Pa]
state1.V = 566 * cm^3 ;  % [m^3]
state3.T = 2000 ;        % [K]
gas.m    = getVariableFromStateEquation("m", state1, gas) ;

% 1-2 (isoentropic compression)
state2.V = state1.V / r ;
state2   = getStateAfterIsoentropicProcessConst(state1, state2, gas) ;

% 2-3 (V=const)
state3 = getStateAfterIsochoricProcess(state2, state3, gas) ;

% 3-4 (isoentropic expansion)
state4.V = state1.V ;
state4   = getStateAfterIsoentropicProcessConst(state3, state4, gas) ;

% Work per unit mass per cycle [J/kg]
qIn  = gas.cv * ( state3.T - state2.T ) ;
qOut = gas.cv * ( state4.T - state1.T ) ;
l = qIn - qOut ;

% Thermal efficiency
eta = l / qIn 

% Total work per cycle [J]
L = gas.m * l 

% Displacement volume [m^3]  and mean effective pressure [Pa]
V = state1.V - state2.V ;
pme = L / V