Another Approach to the Extended Stokes’ Problems for the Oldroyd-B Fluid

Figure 4

The contour path for the case 𝜆>𝜆_𝑟>0 with the condition 𝜔₁<𝜔<𝜔₂. The poles 𝑠=𝑖Ω and 𝑠=−𝑖Ω are for the second problem only.