| As the development of technology, the equipments in differnet fields, such aselectronics, mechanism, aerospace, biology, medicine, turn to minitype fromtraditional technics. Micro-electromechanical systems (MEMS) become an risingtechnolgoy field. The minimization of system structures brings the industry fileds toa position that facing to both opportunities and challenges. On the one hand, severaldifficulties, such as harder to dissipate heat, lower transform efficiency ofthermophotovaltic system, are produced. On the other hand, the special properties ofmicro-scale structures provide some new methods and ideas to solve those problems.Recently, there have been some researches about meeting the industrial applicationrequirments by the radiation properties of micro-structures. However, since theresearches about micro-structure radiation are not mature, there are still lots ofrequirements in practical application can not be satisfied.Based on the above background, in order to develop the radiation propertycontrol technology of microscale structure surface to solve industrial problems andimprove the application system performance, this paper does some researches aboutthe spectral radiation properties of periodic micro-scale structure surface. Theresearch of this paper aims to the application field that take radiation as the mainenergy transition and transfer way, such as thermophotovoltaic system andaerospace thermal control system. In this study, two methods are proposed to widenthe equivalent absorptance wavelength band. And it also proposes three newstructures for active control of radiaiton properties. The spectral properties andresonance mechanism are studied by rigourous coupled-wave analysis combinedwith the equivalent LC circuit model theory. It is found that the radiation propertiesof systems are much improved and meet the requirment of practicle applicationsbetter. The scope of present study contains three parts:There are several different adjust mechanisms for the radiation properties ofperiodic grating structure surface. The changing law of grating radiation propertieswith incident ray, grating structure demensions and grating materials areinvestigated in this paper. The results show that the absorptance peaks excited byMagnetic Polaritons (MPs) are properer for radiaiton adjustment than that excited bySurface Plasmon/Phonon Polaritons (SPPs). The absorptance peaks excited by MPscan be adjusted by changing the grating structure dimensions. The absorbency ofmaterials is inversely proportional to (κ/n)2. Aluminum, gold and silver are proper tothe materials of periodic micro-structure due to their strong electrical conductivityand constant absorptance in mid-and far-infrared wave band. The high absorptance peaks excited by simple grating are too narrow to meetthe requirement of aerospace thermal control system. This paper proposes adual-groove grating structure and a complex dual-groove grating structure forpassive control of system radiation property. It is proved that these two structuresincreased the effecitve wave band within interested wavelength band by combiningabsorptance peaks excited in different wavelength through structrue design. And thesimulation shows that these two structures are promising for specral radiaitonproperty improvement.It is helpful to improve the flexbility and manoeuvrability of radiation heatdisspation equipments. A sliding cover board grating structure, a filling solutiongrating structure and a comb-driven micro-actuator grating structure are proposedfor active control of system spectal radiaiton properties. The resonance mechanismand adjusting laws are investigated. It is proved that the absorptance peaks can beadjusted by changing the thickness and position of cover board, height of fillingsolutions and geometry dimensions or displacement of comb finger. This designprovides the posibility of adjusting system radiation property after the graitngstructures are frabricated, thus enable change the spectral properties according toenvironment demand. |
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