Abstract
The flat-oval consists of two semicircular-arcs with radius ρ and two straight line-segments with lenght 2(α - ρ), and it is very similar to the ellipse. A stress-fields for the infinite plate having a fiat-oval hole due to in-plane uniform tension at thr far-field are computed accurately by means of two-dimensional body force method(BFM). As a result, we understood that: 1) stress distribution for the infinite plate having a flat-oval hole is almost same as that for the infinite plate having an elliptic hole; 2) stress concentration factor(SCF) in the case of a fiat-oval hole, α_t^f, is greater than SCF in the csse of an elliptic hole, α_t^e, that is, α_t^f > α_t^e; 3) the SCF α_t^f is a linear function of the shape parameter √<α/ρ>, and it can be expresed as α_t^f = 0.89912 + 2.1156√<α/ρ>; and 4) the ratio of SCF for a fiat-oval hole and that for an elliptic hole, α_t^e/α_t^e, approaches the value 1.0578 as √<α/ρ> → ∞.