Enclosed parking garages require mechanical ventilation fans to dilute concentrations of pollutants emitted from vehicles,which contributes to energy use and peak electricity demand.This study develops and applies a s...Enclosed parking garages require mechanical ventilation fans to dilute concentrations of pollutants emitted from vehicles,which contributes to energy use and peak electricity demand.This study develops and applies a simulation framework combining multi-zone airflow and contaminant transport modeling,fan affinity laws,and realistic assumptions for vehicle traffic patterns and carbon monoxide(CO)emissions to improve our ability to predict the impacts of various ventilation control strategies on indoor air quality and fan energy use in parking garages.The simulation approach is validated using measured data from a parking garage case study and then applied to investigate fan energy use,peak power demand,and resulting CO concentrations for four different ventilation control strategies in a model underground parking garage under a variety of assumptions for model inputs.The four ventilation control strategies evaluated include one simplistic schedule(i.e.,Always-On)and three demand-based strategies in which fan speed is a function of CO concentrations in the spaces,including Linear-Demand Control Ventilation(DCV),Standardized Variable Flow(SVF),and a simple On-Off strategy.The estimated annual average fan energy consumption was consistently lowest with the Linear-DCV strategy,resulting in average(±standard deviation)energy savings across all modeled scenarios of 84.3%±0.4%,72.8%±3.6%,and 97.9%±0.1%compared to SVF,On-Off,and Always-On strategies,respectively.The utility of the framework described herein is that it can be used to model energy and indoor air quality impacts of other parking garage configurations and control scenarios.展开更多
Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, ...Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, and Cu in PM10 samples, were determined using atomic absorption spectrometer （AAS）. Beta attenuation method was applied to observe the hourly variation of PM10 levels. Results show that average PM10 concentrations at the entrance and at the exit were 101.3 μg/m3 and 234.4 μg/m3, respectively, and average PM2.5 concentrations at the entrance and at the exit were 47.7 μg/m3 and 62.7μg/m3, respectively. PM pollution was worse at the exit than at the entrance. Hourly PMlo concentration was weakly correlated with traffic flow. Regarding element concentrations, the most enriched element in PM10 samples was Fe. Re-suspension of soil dust at the exit is an important source of PM10.展开更多
基金This work was supported by Nagle Energy Solutions,LLC,which provided empirical data utilized in this studyThis study was funded in part by an ASHRAE New Investigator Award to Mohammad Heidarinejad and an ASHRAE Graduate Grant-In-Aid to Afshin Faramarzi.
文摘Enclosed parking garages require mechanical ventilation fans to dilute concentrations of pollutants emitted from vehicles,which contributes to energy use and peak electricity demand.This study develops and applies a simulation framework combining multi-zone airflow and contaminant transport modeling,fan affinity laws,and realistic assumptions for vehicle traffic patterns and carbon monoxide(CO)emissions to improve our ability to predict the impacts of various ventilation control strategies on indoor air quality and fan energy use in parking garages.The simulation approach is validated using measured data from a parking garage case study and then applied to investigate fan energy use,peak power demand,and resulting CO concentrations for four different ventilation control strategies in a model underground parking garage under a variety of assumptions for model inputs.The four ventilation control strategies evaluated include one simplistic schedule(i.e.,Always-On)and three demand-based strategies in which fan speed is a function of CO concentrations in the spaces,including Linear-Demand Control Ventilation(DCV),Standardized Variable Flow(SVF),and a simple On-Off strategy.The estimated annual average fan energy consumption was consistently lowest with the Linear-DCV strategy,resulting in average(±standard deviation)energy savings across all modeled scenarios of 84.3%±0.4%,72.8%±3.6%,and 97.9%±0.1%compared to SVF,On-Off,and Always-On strategies,respectively.The utility of the framework described herein is that it can be used to model energy and indoor air quality impacts of other parking garage configurations and control scenarios.
基金supported by the Fundamental Research Funds for the Central Universities of China(Grant No. 2011PY049)
文摘Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, and Cu in PM10 samples, were determined using atomic absorption spectrometer （AAS）. Beta attenuation method was applied to observe the hourly variation of PM10 levels. Results show that average PM10 concentrations at the entrance and at the exit were 101.3 μg/m3 and 234.4 μg/m3, respectively, and average PM2.5 concentrations at the entrance and at the exit were 47.7 μg/m3 and 62.7μg/m3, respectively. PM pollution was worse at the exit than at the entrance. Hourly PMlo concentration was weakly correlated with traffic flow. Regarding element concentrations, the most enriched element in PM10 samples was Fe. Re-suspension of soil dust at the exit is an important source of PM10.
