Magnetic refrigeration is one of the promising alternative cooling technologies due to high theoretical coefficients of performance and eco-friendliness as can operate without chlorofluorocarbon refrigerant derivatives. While the compact size is an advantage, size limitation for the magnet array and heat exchanger can be a concern in these systems. To enhance the magnetic field, Halbach magnet arrays are one of the solutions in magnetic refrigeration applications. For such systems, identification of the magnetic field within the aperture inside the Halbach magnet array is crucial. In this study, the magnetic field inside a cylindrical Halbach array formed from 12 NdFeB magnets is investigated both experimentally and theoretically. An experimental setup was built to measure the magnetic field within the problem domain in cylindrical coordinates. Calibration of the recorded data was ensured with a reference test sample. Magnetic field values were also calculated using a theoretical model that was developed based on the magnet characteristics and geometry of the Halbach magnet array. Results from experimental and theoretical analyses were compared and were found to be in close agreement. Once the magnetic field map within the aperture was obtained, corresponding entropy changes and heat flux values were calculated. Resulting data was implemented into ANSYS to observe the thermo-fluidic behavior of the magnetic refrigeration system. Results proved that the thermal behavior of the system noticeably depends on the magnitude of the magnetic field acting on the magnetocaloric material which is concentrically placed inside the array.