Future Trends of Deep Sea Bed Mining Technology

The present status of deep sea bed mining technology for polymetallic nodules has been critically examined in light of its history of development the UNCLoS (the United Nation Convention on the Law of the Sea) regime and the current trends in research.The critical technologies have been highlighted and the need for system integration underscored. The deep sea bed environment and the engineering challenge were presented and the necessary features of the deep sea bed mining system for commercial mining was analyzed. The key accomplishments, problems and future bends in research in the development of the mining system are also discussed. Finally, it points out that the technology gaps can be filled by the bine commercial mining is undertaken as a result of market conditions in its favor.

Study of Total Process Energy Integration

The energy utilization consistency method in process integration extracts the key component of process energy utilization, and simplifies the procedure of process analysis and integration. The method allows the conversion of the total process energy integration into a synthesis problem of a pseudo-heat exchanger network. The advantages of using the energy utilization consistency and the pseudo-temperature methods are presented by two examples of integration of large-scale complex processes. The improved genetic algorithm is proved to be an effective tool in the retrofitting procedures.

Effects of Nozzle-Strut Integrated Design Concepton on the Subsonic Turbine Stage Flowfield

In order to shorten aero-engine axial length,substituting the traditional long chord thick strut design accompanied with the traditional low pressure(LP) stage nozzle,LP turbine is integrated with intermediate turbine duct(ITD).In the current paper,five vanes of the first stage LP turbine nozzle is replaced with loaded struts for supporting the engine shaft,and providing oil pipes circumferentially which fulfilled the areo-engine structure requirement.However,their bulky geometric size represents a more effective obstacle to flow from high pressure(HP) turbine rotor.These five struts give obvious influence for not only the LP turbine nozzle but also the flowfield within the ITD,and hence cause higher loss.Numerical investigation has been undertaken to observe the influence of the Nozzle-Strut integrated design concept on the flowfield within the ITD and the nearby nozzle blades.According to the computational results,three main conclusions are finally obtained.Firstly,a noticeable low speed area is formed near the strut's leading edge,which is no doubt caused by the potential flow effects.Secondly,more severe radial migration of boundary layer flow adjacent to the strut's pressure side have been found near the nozzle's trailing edge.Such boundary layer migration is obvious,especially close to the shroud domain.Meanwhile,radial pressure gradient aggravates this phenomenon.Thirdly,velocity distribution along the strut's pressure side on nozzle's suction surface differs,which means loading variation of the nozzle.And it will no doubt cause nonuniform flowfield faced by the downstream rotor blade.