A new modification of an earlier published model for the calculation of energy spectra of primary knocked atoms formed in the material under neutron, proton or other particle irradiation is being considered in the present paper. The new approach takes into account the angular momenta of interacting particles within the limits of the compound nucleus model. It is found that the model allows to carry out more accurate estimation of the quantities of nuclear reaction products. It also modifies the shape of the PKA energy spectrum. Control calculations for the nuclear reactions caused in proton irradiated copper have been made. The results of these calculations are in good agreement with the excitation functions for the nuclear reactions.