In this paper,the main factors impacting the plug flow pattern of a clearwell were investigated by integrating pilot-scale,full-scale clearwell tracer testing and computa-tional fluid dynamics(CFD)simulation.It was fo...In this paper,the main factors impacting the plug flow pattern of a clearwell were investigated by integrating pilot-scale,full-scale clearwell tracer testing and computa-tional fluid dynamics(CFD)simulation.It was found that pilot tracer testing,full-scale tracer testing and CFD simulation all demonstrated that the correlation between the ratio of t_(10)/T and L/W can be approximately expressed by:t_(10)/T=0.1894ln(L/W)−0.0494.This study confirmed that the installation of baffles within clearwells is an efficient way to optimize their configuration.In addition,the inlet velocity has a minimal contribution to the ratio of t_(10)/T.However,the ratio of turning channel width to channel width(d/W)significantly contributes to the ratio of t_(10)/T.The optimal ratio of d/W is 0.8-1.2 for maintaining better plug flow pattern.The number of turning channels is one of the main factors that impact the ratio of t_(10)/T.When increasing the number of turning channels,a lower ratio of t_(10)/T is obtained.展开更多
基金This work was supported by the National High-Tech Research and Development(863)Program of China(Grant No.2002AA601120)by the Foundation from Beijing Science and Technol-ogy Commission(Grant No.D0605004040421).
文摘In this paper,the main factors impacting the plug flow pattern of a clearwell were investigated by integrating pilot-scale,full-scale clearwell tracer testing and computa-tional fluid dynamics(CFD)simulation.It was found that pilot tracer testing,full-scale tracer testing and CFD simulation all demonstrated that the correlation between the ratio of t_(10)/T and L/W can be approximately expressed by:t_(10)/T=0.1894ln(L/W)−0.0494.This study confirmed that the installation of baffles within clearwells is an efficient way to optimize their configuration.In addition,the inlet velocity has a minimal contribution to the ratio of t_(10)/T.However,the ratio of turning channel width to channel width(d/W)significantly contributes to the ratio of t_(10)/T.The optimal ratio of d/W is 0.8-1.2 for maintaining better plug flow pattern.The number of turning channels is one of the main factors that impact the ratio of t_(10)/T.When increasing the number of turning channels,a lower ratio of t_(10)/T is obtained.