二成分瞬間速度と瞬間圧力の同時測定による二次元乱流噴流の構造に関する研究 : 速度変動と圧力変動の相互相関係数およびエネルギ収支の実験的評価(流体工学,流体機械) On the Structure of Two-Dimensional Turbulent Jet by the Simultaneous Measurement of Instantaneous Two Velocity Components and Static Pressure : Experimental Evaluations of Cross-Correlation Coefficient between Velocity and Pressure Fluctuations and Turbulent Energy Budget(Fluids Engineering)

The simultaneous measurement of instantaneous two velocity components and static pressure is carried out in two-dimensional turbulent jet by the combination of X-type hot-wire and static pressure probes. The yaw-insensitive static pressure probe is newly developed, which is much smaller (i.e., the outer diameter of the probe is 0.5mm and the diameter of the side holes is 0.2mm) than the previously developed one. The results show that the κ_1^<-7/3> power low is clearly observed in the pressure spectrum, where κ_1 is the streamwise wavenumber. The distributions of cross-correlation between fluctuating velocity u, v and fluctuating static pressure p are consistent with the past model of coherent vortex structure in the two-dimensional turbulent jet. The turbulent energy budget is estimated and it is found to be similar to that estimated by Bradbury (1965), who did not measure instantaneous pressure. The present simultaneous measurement enables us to estimate the breakdown of the diffusion term in the energy budget, i.e., turbulent transport and pressure diffusion terms.