octave Integration

This example demonstrates how to use fluids from octave.

Source Code

  1% Test suite for fluids library in Octave
  2% Requires pythonic package or oct2py
  3
  4pkg load pythonic  % Load Python interface
  5
  6function test_fluids()
  7    try
  8        % Test basic module import
  9        fluids = py.importlib.import_module('fluids');
 10        printf('✓ Successfully imported fluids\n');
 11        printf('✓ Fluids version: %s\n', char(fluids.__version__));
 12        
 13        % Test basic Reynolds number calculation
 14        Re = double(fluids.Reynolds(pyargs('V', 2.5, 'D', 0.1, 'rho', 1000, 'mu', 0.001)));
 15        printf('✓ Reynolds number calculation successful: %f\n', Re);
 16        assert(Re > 0);
 17        
 18        % Test friction factor calculation
 19        fd = double(fluids.friction_factor(pyargs('Re', 1e5, 'eD', 0.0001)));
 20        printf('✓ Friction factor calculation successful: %f\n', fd);
 21        assert(fd > 0 && fd < 1);
 22        
 23        printf('\nAll basic tests completed successfully!\n');
 24        
 25    catch err
 26        printf('Error occurred: %s\n', err.message);
 27        rethrow(err);
 28    end
 29end
 30
 31function test_atmosphere()
 32    try
 33        fluids = py.importlib.import_module('fluids');
 34        % Test ATMOSPHERE_1976 class
 35        atm = fluids.ATMOSPHERE_1976(pyargs('Z', 5000));
 36        
 37        printf('\nTesting atmosphere at 5000m elevation:\n');
 38        printf('✓ Temperature: %.4f\n', double(atm.T));
 39        printf('✓ Pressure: %.4f\n', double(atm.P));
 40        printf('✓ Density: %.6f\n', double(atm.rho));
 41        
 42        % Test derived properties
 43        printf('✓ Gravity: %.6f\n', double(atm.g));
 44        printf('✓ Viscosity: %.6e\n', double(atm.mu));
 45        printf('✓ Thermal conductivity: %.6f\n', double(atm.k));
 46        printf('✓ Sonic velocity: %.4f\n', double(atm.v_sonic));
 47        
 48        % Test static methods
 49        g_high = double(fluids.ATMOSPHERE_1976.gravity(pyargs('Z', 1E5)));
 50        printf('✓ High altitude gravity: %.6f\n', g_high);
 51        
 52        v_sonic = double(fluids.ATMOSPHERE_1976.sonic_velocity(pyargs('T', 300)));
 53        printf('✓ Sonic velocity at 300K: %.4f\n', v_sonic);
 54        
 55    catch err
 56        printf('Error in atmosphere tests: %s\n', err.message);
 57        rethrow(err);
 58    end
 59end
 60
 61function test_tank()
 62    try
 63        fluids = py.importlib.import_module('fluids');
 64        % Test basic tank creation
 65        T1 = fluids.TANK(pyargs('V', 10, 'L_over_D', 0.7, 'sideB', 'conical', 'horizontal', false));
 66        printf('\nTesting tank calculations:\n');
 67        printf('✓ Tank length: %.6f\n', double(T1.L));
 68        printf('✓ Tank diameter: %.6f\n', double(T1.D));
 69        
 70        % Test ellipsoidal tank
 71        tank_ellip = fluids.TANK(pyargs('D', 10, 'V', 500, 'horizontal', false, ...
 72                                      'sideA', 'ellipsoidal', 'sideB', 'ellipsoidal', ...
 73                                      'sideA_a', 1, 'sideB_a', 1));
 74        printf('✓ Ellipsoidal tank L: %.6f\n', double(tank_ellip.L));
 75        
 76        % Test torispherical tank
 77        DIN = fluids.TANK(pyargs('L', 3, 'D', 5, 'horizontal', false, ...
 78                                'sideA', 'torispherical', 'sideB', 'torispherical', ...
 79                                'sideA_f', 1, 'sideA_k', 0.1, 'sideB_f', 1, 'sideB_k', 0.1));
 80        
 81        printf('✓ Tank max height: %.6f\n', double(DIN.h_max));
 82        printf('✓ Height at V=40: %.6f\n', double(DIN.h_from_V(40)));
 83        printf('✓ Volume at h=4.1: %.5f\n', double(DIN.V_from_h(4.1)));
 84        printf('✓ Surface area at h=2.1: %.5f\n', double(DIN.SA_from_h(2.1)));
 85        
 86    catch err
 87        printf('Error in tank tests: %s\n', err.message);
 88        rethrow(err);
 89    end
 90end
 91
 92function benchmark_fluids()
 93    fluids = py.importlib.import_module('fluids');
 94    printf('\nRunning benchmarks:\n');
 95    
 96    % Benchmark friction factor calculation
 97    printf('\nBenchmarking friction_factor:\n');
 98    tic;
 99    for i = 1:1000
100        fluids.friction_factor(pyargs('Re', 1e5, 'eD', 0.0001));
101    end
102    t1 = toc;
103    printf('Time for 1000 friction_factor calls: %.6f seconds\n', t1);
104    printf('Average time per call: %.6f seconds\n', t1/1000);
105    
106    % Benchmark tank creation
107    printf('\nBenchmarking TANK creation:\n');
108    tic;
109    for i = 1:1000
110        fluids.TANK(pyargs('L', 3, 'D', 5, 'horizontal', false, ...
111                          'sideA', 'torispherical', 'sideB', 'torispherical', ...
112                          'sideA_f', 1, 'sideA_k', 0.1, 'sideB_f', 1, 'sideB_k', 0.1));
113    end
114    t2 = toc;
115    printf('Time for 1000 TANK creations: %.6f seconds\n', t2);
116    printf('Average time per creation: %.6f seconds\n', t2/1000);
117end
118
119% Run all tests
120printf('Running fluids tests from Octave...\n');
121test_fluids();
122test_atmosphere();
123test_tank();
124benchmark_fluids();
125printf('\nAll tests completed!\n');

Requirements

Usage Notes

  • The example demonstrates basic integration with fluids

  • 1300 microsecond friction factor, 1800 microsecond tank creation observed by author