Theories of linear stability, reinforcement, or degradation of small disturbances examine the velocity applied to the average velocity of the flow. When the boundary layer flow expands linearly in the early stages of its development, the input boundary conditions of the computational domain are determined using the results of the linear stability solution. In order to better adapt to laboratory results, spatial stability analysis is used. Using an algebraic mapping, the physical domain is converted to a computational domain. To solve the Or-Samerfeld equation, a spectral method has been used that has led to the solution of a special value problem. Comparing laboratory results and results of spatial and temporal perturbation stability analysis, it can be stated that spatial perturbation growth analysis more accurately describes the instability characteristics of the perturbation boundary flow. Small frequencies are much more accurate.