vortex time

According to distribution of pressure of blade surface at different time of outdoor units, it is shown that interaction between tip vortex and bellmouth is the major factor of unsteady fluctuation of blade surface and has large effect on discrete frequency noise of outdoor units.

室外机不同时刻叶片表面压力分布表明，叶尖涡与导风罩干涉是室外机中叶片表面非定常力脉动的主要原因，影响室外机离散频率噪声。

In this paper, the subsonic unsteady aerodynamic performance of a noncoplanar wing-tail combination can be computed on condition that the velocity potential function of unsteady vortex ring is taken as an elementary solution and the method of time history ( MTH) is used.

本文以非定常涡环速度势函数为基本解，应用时间历程方法，计算非共面机一尾翼组合体的非定常气动力性能。

Firstly, the characteristics of vortex signal at low flowrate are analyzed in time-domain and frequency-domain respectively. The source and representation of noise components are summarized.

通过对小流量时涡街信号进行时域和频域分析，总结有用信号、噪声的特征及形式。

At the same time, the heat and mass balance of the small-scale solar absorption system which uses the dual chamber vortex generator is analyzed. A new generator model which has a tangential inlet is set up.

同时分析了采用本文所提出的双室涡旋发生器的小型太阳能吸收式制冷系统的热质平衡特性。

Of particular significance to the theory in flow over bluff body and the experiment analysis methods was the definition of vortex shedding character dimension, which was first proposed by the researcher to analyze the time-dependent wake flow quantitatively.

首次提出旋涡脱落特征尺度来定量分析非稳态尾流，是一次意义重大的钝体绕流理论和实验分析方法上的创新。