Thermoacoustic phenomena can be modeled by means of analytical closed-forms and numerical models. The analytical solution can be obtained with a minimum computational cost, whereas the numerical approach is computationally expensive. The former, however, provides an average solution along the engine, while within the numerical simulations non-stationary phenomena can be observed. This paper includes results related to the modeling of the operation of a thermoacoustic engine both by means of the analytical approach and numerical models. Some computational details and assumptions adopted in both models are discussed. The main focus is placed on the numerical approach, where the model size (number of pores analyzed) is taken into account. The results show differences between a single-pore symmetrical model and multiple-pore ones. The object of the comparisons is to determine the reliability of the modeling of the operation of a thermoacoustic engine and to evaluate sources of discrepancy between models, both numerical ones, as well as the numerical and analytical approaches. (C) 2017 Elsevier Ltd. All rights reserved.