基于压力自适应平衡的深海气密采水系统

Study of Gas-tight Deep-sea Water Sampling System Based on Pressure Self-adaptive Equalization

深海海水中的气体研究是当前海洋科学研究的前沿课题,而如何快速地采集到能真实反映原位气体成分组成信息的海水样品,是近几年来海洋技术领域研究的热点与难点。现有常规的采水器主要用于采集水样,很少考虑气体的保存,不能满足深海海水中的气体研究的要求。为此,利用压力自适应平衡技术和有效可靠的密封方法,研制开发出一套新型深海气密采水系统,很好地解决了上述问题。根据流体力学知识,建立了深海气密采水器的压力自适应平衡器容积变化模型,指出压力自适应平衡器容积约要大于等于气密采水器容积的12.24%,而且静水压力越大、温度变化越大,压力自适应平衡器容积就要越大。采用聚四氟乙烯包覆O形圈来实现压力自适应平衡腔与活塞之间的密封是种有效可靠的动密封方式。通过实验室气密性试验和第一次海试验证了深海气密采水系统设计的可行性。

In ocean science,while the study of dissolved gases in deep-sea water is something of disciplinary frontier,how to obtain seawater samples that can quickly collect the in-situ information on gas components remains a difficult issue.Furthermore,with the existing seawater samplers,the preservation of dissolved gases is often overlooked.The shortcoming of existing routine seawater samplers motivates the design of a new gas-tight deep-sea water sampling system （GTWS）,with which the dissolved gases can be well preserved and gases components＇ in-situ intact information obtained.Based on the pressure self-adaptive equilibrium technology and effective and reliable sealing,such a GTWS is developed.The pressure self-adaptive equalizer （PSAE） is described in details.Developed according to hydrodynamics principles,the PSAE＇s capacity model illustrates that the PSAE＇s capacity is supposed to be bigger than or equal to about 12.24% of the GTWS＇s capacity.The PSAE＇s capacity is in positive correlation with the surrounding water pressure and diversity of temperature （i.e.,the greater the hydrostatic pressure and temperature variation are,the greater the PSAE＇s capacity should be.） As a kind of effective and reliable dynamic seal,polytetrafluoroethylene-coated O ring is used to achieve the dynamic seal between PSAE＇s piston and cavity.The feasibility of this GTWS＇s design is verified by gas tightness tests in laboratory and the first sea trial.