简介:摘要:本文根据北京阿苏卫垃圾焚烧发电厂项目引进比利时西格斯多级炉排及其控制炉排的SIGMA系统为例,讨论介绍其自动燃烧控制方式,并对炉排炉的炉膛温度控制进行讨论和探索。
简介:针对微弱重力信号测量中加速度计的数字输出接口电路应具有高分辨率的问题,引入了开关电容(SC)sigma—delta调制器(SDM).基于SDM的工作原理和拓扑结构,分析了过采样比、内部量化器位数以及级联结构对提高微弱信号检测精度的影响,设计了满足加速度计接口电路高分辨率要求的理想二阶1位低失真SDM结构.通过研究各模块在SC电路实现中的非理想特性及其对电路功耗的影响,设计了基于不同带宽的低功耗SDM实现参数,给出了相应的功耗估计.利用Simulink对各设计方案进行了时域的行为级仿真.结果表明,所设计SDM在低功耗的前提下其分辨率可达21位以上,其电路实现参数可用于指导晶体管级电路设计.
简介:Asemi-implicit3-Dnumericalformulationforsolvingnon-hydrostaticpressurefree-surfaceflowsonanunstructured,sigmagridisproposed.Pressure-splittingand9semi-implicitmethodsareinheritedandreformedfromCasulli'sz-coordinateformulation.Thenon-orthogonalsigma-coordinatetransformationleadstoadditionalterms.Theresultinglinearsystemforthenon-hydrostaticcorrectionisdiagonallydominantbutunsymmetric,anditissolvedbytheBiCGstabmethod.Incontrastwithz-coordinatenon-hydrostaticmodels,thenewmodelfitsverticalboundariesmuchbetter,whichisimportantforthelong-timesimulationofsedimenttransportandriverbeddeformation.Alock-exchangedensityflowiscomputedtodeterminewhetherthenewschemeisabletosimulatenon-hydrostaticfree-surfaceflows.ThenewmodelisfurtherverifiedusingthefielddataofanaturalriverbendofthelowerYangtzeRiver.Goodagreementbetweensimulationsandearlierresearchresults,fielddataisobtained,indicatingthatthenewmodelisapplicabletohydraulicprojectsinrealrivers.