Pipe Flow Calculator

import math

def calculate_pipe_flow(d_mm, q_m3_h=None, v_m_s=None):
    """
    Calculate flow parameters using the continuity equation Q = A * v.
    """
    d_m = d_mm / 1000.0
    area_m2 = (math.pi * (d_m ** 2)) / 4.0
    
    if q_m3_h is not None:
        q_m3_s = q_m3_h / 3600.0
        v = q_m3_s / area_m2
    elif v_m_s is not None:
        v = v_m_s
        q_m3_s = v * area_m2
    else:
        raise ValueError("Provide either flow rate or velocity.")
        
    return {
        "area_m2": area_m2,
        "velocity_m_s": v,
        "flow_m3_h": q_m3_s * 3600.0,
        "flow_L_s": q_m3_s * 1000.0,
        "flow_L_min": q_m3_s * 60000.0
    }

# Example
res = calculate_pipe_flow(
    d_mm=80,
    q_m3_h=36
)
print(f"Velocity: {res['velocity_m_s']:.3f} m/s")
print(f"Flow Rate: {res['flow_m3_h']:.2f} m³/h ({res['flow_L_s']:.2f} L/s)")
print(f"Pipe Area: {res['area_m2']:.6f} m²")

function res = pipe_flow(d_mm, q_m3_h, v_m_s)
    d_m = d_mm / 1000;
    area = (pi * d_m^2) / 4;
    
    if nargin > 1 && ~isempty(q_m3_h)
        q_m3_s = q_m3_h / 3600;
        v = q_m3_s / area;
    else
        v = v_m_s;
        q_m3_s = v * area;
    end
    
    res.velocity = v;
    res.flow_m3_h = q_m3_s * 3600;
    res.flow_L_s = q_m3_s * 1000;
end

% Example
res = pipe_flow(80, 36, []);
fprintf('Velocity: %.2f m/s\n', res.velocity);