Compressor (2P) modeling

Question

Problem with compressor component (2P) using two_port steady block. Please find the code below. Unable to raise mass flow and pressure at the same time. Errors associated with component equations.

  component compressor_final2< foundation.two_phase_fluid.two_port_steady
    
% compressor_final2 
inputs
     % Pressure differential
    %P = {0, 'MPa'}; % P:left
    
    % Mass flow rate
    %M = {0, 'kg/s'}; % M:left
end

nodes
    S = foundation.mechanical.rotational.rotational; 
% S:Left  
end
outputs
    speed={90,'rad/s'}; %Wc:right
    torque={2,'N*m'}; %t:right
    P_b={20, 'kPa'}; % pressure at B
end

parameters
    Vp={0.21,'m^3'}; % Plenum volume
    di={0.02,'m'}; % inlet diameter
    pi_c={1.5, '1'}; % pressure ratio
    length={1.253,'m'}; % L_c
    nvol={0.85,'1'}; % volumetric efficiency
    N_C={3500,'rpm'}; % Compressor required speed
end

variables   
t={20,'N*m'}; % compressor torque

power= {0,   'kW'     }; % Work done on the fluid by the source

%p_B={0,'MPa'}; % Pressure @ B

end

function setup
% Geometry
flow_area_A=pi*di^2/4;
flow_area_B=pi*di^2/4;
conduction_length=length;
end

branches
    t:S.t->*;
    mdot_A: A.mdot ->* ;
    mdot_B: B.mdot ->*;
end



equations
    
        
    let 
         % Domain parameters
        u_min         = A.u_min;
        u_max         = A.u_max;
        unorm_TLU     = A.unorm_TLU;
        p_TLU         = A.p_TLU;
        s_TLU         = A.s_TLU;
        u_sat_liq_TLU = A.u_sat_liq_TLU;
        u_sat_vap_TLU = A.u_sat_vap_TLU;

        % Across variables
        p_A = A.p;
        p_B = B.p;
        
        % Mass flow rate from port A to port B
        mdot = mdot_A;
        
        % Isentropic work based on entropy
        power_compressible   = mdot * (u_B + p_B*v_B - u_A - p_A*v_A);
        % Incompressible approximation based on pressure differential
        power_incompressible = mdot * (p_B - p_A)*(v_A + v_B)/2;

        % Average normalized internal energy
        unorm_avg = (unorm_A + unorm_B)/2;
        
    in 
    
    % Torque and speed calculations
    %t==Tc;
    %S.w==2*N_C*pi/60;
    %Commanded mass flow rate    
    mdot==(1/v_A)*Vp*S.w*nvol;
    
    % Energy balance    
   
    % Mass balance
    
    % reconciliation
    %mdot_A+mdot_B==0;
 
    %Commanded pressure difference
    p_B-pi_c*p_A==0;
    
    % Energy balance
    
    power == ...
            if le(unorm_avg, 0), ...
                power_incompressible ...
            elseif ge(unorm_avg, 1), ...
                power_compressible ...
            else ...
                (1-unorm_avg) * power_incompressible + unorm_avg * power_compressible ...
            end;
    S.w*t==power;    
    Phi_A+Phi_B+power==0;
    
    
    % outputs equations
    t==torque;
    S.w==speed;
    B.p==P_b;
    end
end
end

Compressor (2P) modeling

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Compressor (2P) modeling

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