| OCR Text |
Show - 7 - (7) where Pb and cb are the density of the burned gas and the sound velocity in the burned gas, respectiv ly. The emitted sound energy was evaluated in the burned gas side. If the sound source is assumed to be a point source and the sound energy loss in the medium is negligible, the sound energy flux I can be deter-o mined dividing I by the surface area 47f,2, when the microphone set at x = " s 1.e., (8) The sound pressure P at the micropho!le can be determined using the following o relation. (9) where Po and Co are the density and the sound velocity of the gas at the microphone, respectively. From Eq. (5) through Eq. (9), the following equation can be derived. 1 Po = [POCOc (PU _ 1)2p~Su3~(~)2U)2 4Pbcb Pb ,2 2 1 3 1 = (PoCoc )2( Pu _ 1)PuSu2.l~u2 4PbCb Pb ' 2 (10) For a given flow condition at a burner and a given microphone location, d", Pu'Po' and Co are constant. Thus, the following simplified relation must be valid, (11) |
