曝气诱导内波破坏水库水温分层的过程与效果

中国环境科学2015，35(2)：434~441ChinaEnvironmentalScience曝气诱导内波破坏水库水温分层的过程与效果孙昕，卞晶，解岳，叶丽丽，马兰(西安建筑科技大学环境与市政工程学院，陕西西安710055)摘要：针对传统的水库破坏分层技术的低效率、高能耗等普遍问题，研制了能模拟基于自然对流而形成水温分层的中试模型水库，研究了曝气诱导形成内波混合破坏水温分层的可行性，过程和效果．扬水曝气产生的周期性出流能作为扰动源，在分层水环境中诱导形成内波．内波频率及波幅与曝气量有关．在曝气量0．07～0．28m／(I112．h)，跃温层温度梯度0．29~0．48~C／m的中试条件下，内波破坏分层过程主要以减小表层和底层水温差别、驱使跃温层下潜、等温层变薄为特征，破坏分层的速度与曝气量正相关、与温度梯度负相关．内波通过垂向振荡和横向传播，促进不同温度的水层之间的热交换．相对传统的循环水流混合，在温度梯度约0．32~C／m和0．46C／m的条件下，当曝气量从0．07m／(m2-h)逐渐增加到O．28m／(m2．h)时，内波混合可分别将破坏分层效率提高25．0％～40．0％和41．2％～60．0％．关键词：曝气：内波；破坏分层：效率；影响因素；水库中图分类号：X524文献标识码：A文章编号：1000—6923(2015)02—0434-08Processandefeetivenessofdestratificationbyaeration—inducedinternalwavesinareservoir．SUNXin。．BIANJing，XIEYue，YELi-li，MALaJl(SchoolofEnvironmentalandMunicipalEngineering，Xi’anUniversityofArchitectureandTechnology，Xi’all710055China)．ChinaEnvironmentalScience，2015，35(2)：434~441Abstract：AimingatthecommonproblemsofconventionaldestratificationtechnologiessuchashighenergyconsumptionandlOWenergyefnciency．apilotmodelreservoirwithathermalstructureevolvedfromthenaturalconvectionwasdevelopedandconstructed，thefeasibilityofdevelopinginternalwavesinducedbyaerationwasexplored，andtheprocessandeffectivenessofdestratificationbyintemalwaveswereanalyzed．Periodicoutflowfromthewater．1iftingaeratorcouldactasadisturbingsourcetogenerateinternalwavesinstratifiedwaterenvironments，andtheperiodsandamplitudesofinternalwavesdependedontheairflowrate．Undertheexperimentalairflowratesof0．07～0．28m／(m2．h1andtemperaturegradientsofO．29～0．48*C／minthethermocline．thedestratificationprocesswasmainlycharacterizedbyreducingthetemperaturedifferencebetweenepilimnionandhypolimnion，impellingthethermoclinedownwardsandthinningthehypolimnion，thespeedofdestratificationincreasedwiththeairflowratebutdecreasedwiththetemperaturegradient．Heatexchangebetweenwaterlayersofdifferenttemperaturescouldbeenhancedthroughverticalfluctuationsandhorizontalpropagationbyinternalwaves．Comparedwiththeconventionaldestratificationbycirculatedflow，underthetemperaturegradient