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Second Computational Aeroacoustics (CAA) Workshop on ...

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where<br />

d - A2 AI<br />

A x 2<br />

Error limits and the expansi<strong>on</strong> coefficients are used to determine the integral limits Z±.<br />

The integral near the branch points can be replaced by<br />

where<br />

B±=IL°g_Q_(a)daa-y -211 Log_(a-q_)da,a_y<br />

Q±(a)=x(a)._.<br />

Q4 (o0 are free of singularity and zeroes within the respective chosen integral limits.<br />

The simple poles of K(a) are separated as follows:<br />

where<br />

s-+<br />

t" Loge =I L_(a) P Loge (a - v_. )<br />

a-y _ oe-y<br />

L±(a)=K(a). (a- v_).<br />

L± (a) are free of singularity and zeroes within the respective integral limits.<br />

The zeroes of K(a) are similarly separated as<br />

where<br />

Z. = I L°geU(°_) d_ + I L°ge(a-Z") doe,<br />

o_- y o_- y<br />

U(a) is free of singularity and zeroes within the respective integral limit.<br />

Now c<strong>on</strong>sider the integral<br />

K(o0<br />

U(a) - (43)<br />

H(y) =If L°ge G(a) da,<br />

o_- y<br />

Here G(a) is free of singularity and zeroes within the integral limit, and thus represents Q_(a) in Eq. (38),<br />

L+(a) in Eq. (40), U(o0 in Eq. (42), or K(o0 in Eq. (34) if K(a) is free of singularity in that regi<strong>on</strong>. This<br />

integral can be written as<br />

b da<br />

H(y) =i_ Loge[G(oOIG(y)]ot_y da + LogeG(y) I£ ot-y<br />

34<br />

(37)<br />

(38)<br />

(39)<br />

(40)<br />

(41)<br />

(42)<br />

(44)<br />

(45)<br />

i<br />

z<br />

II<br />

|<br />

E

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