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The outboard discharge process of an underwater vehicle navigating in water results in an interaction between cross-flow and jet. The fluid dynamic characteristics generated by jet in cross-flow are important topics in the field of fluids. Based on Reynolds average and large eddy simulation method, a numerical calculation model of jet in cross-flow was established in this paper. Then the flow field characteristics of jet in cross-flow were explored in detail. The accuracy of the current method was verified by comparing the results of averaged velocity and fluctuating pressures with those in related references. The velocity and vorticity characteristics of the near-wall surface upstream and downstream of the orifice were investigated based on the results of numerical simulation. Additionally, the characteristics of the sound field in the vicinity of the orifice were analyzed. The results indicate that the impact of jet in cross-flow on the upstream near wall was confined within the range of 6 times the aperture from the orifice. Flow separation occurs in the downstreams of the orifice within a range of 2-14 times the bore size. Under the interaction between the crossflow and the jet flow, the characteristic vortex structure of counter-rotating vortex pairs (CVP) are formed in the downstreams of the orifice. The CVP is formed near the lower edge of the orifice and persists downstream. The vortex core gradually moves away from the wall along the flow distance, and the influence area gradually expands. The primary source of acoustic energy resulting from the interaction between the cross-flow and the jet is situated in close proximity to the wall. The acoustic energy level near the orifice is higher and exhibits a detached characteristic from the wall. Furthermore, the sound pressure level in the downstreams of the orifice is considerably higher than that upstream. The radiation of the sound field is dependent on the direction of flow and exhibits obvious directional characteristics.
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| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
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