Assessment Of Air Environmental And Research Of Control Strategy For Ventilation And Air-conditioning In Office Buildings

In this paper, a combination of methods of field testing and questionnaire researchfocused on three separate office buildings in Xi’an indoor air environment conditionhad been conducted. The basic data which can reflect the true conditions of Xi’anoffice buildings indoor air environment was obtained via field measurement. Compareindoor air environment and analysis the real thermal comfort condition of the officestaff under different ventilation modes. We also figure out the neutral environmentaltemperature under different ventilation modes. Statistical methods had been applied toanalysis of different factors on human thermal comfort and indoor air environment,and the thermal adaptive behavior of the staff within the office building had beeninvestigated as well. Finally, a new control strategy of ventilation and air-conditioningwas presented for energy cascade utilization.In this paper, contaminant energy utilization factor, contaminant removalefficiency and non-uniform coefficient were used for evaluating the indoor airdistribution performance of different ventilation modes in selected typical room. Thisstudy found out energy utilization factor, contaminant removal efficiency andnon-uniform coefficient is low and had a poor indoor air quality.According to the assessment of indoor air environment condition of the officebuildings, it is noticed that office staff are not very sensitive to indoor air velocity andhumidity. The risk analysis on impact of indoor environmental quality status of variousfactors were analyst by the statistical software SPSS, and the results shows that the ORvalues of the indoor air quality to environmental quality was49.939(strong contact). During heating season, staff neutral temperature is20.6℃, which is0.7℃higher than19.9℃in the natural ventilation of the transition season. It is noticed that the toleranceof room temperature changes with the variation of environment. Comparison of PMVand TSV, PMV model, ignored the potential of human adaptation, cannot reflect theactual thermal comfort situation. The office staff‘s actual thermal comfort temperaturerange is18.4~22.8℃in heating season. Thus, we can reduce winter air temperaturesetting to20℃, which also provide date support to China’s architecture saving energydesign standard.Finally, after comparing natural ventilation with air-conditioning ventilation, andthe investigation of the adaptive behavior of the staff within the office building, thepreliminary design concept for a new type control strategies of ventilation and airconditioning was composed, basic on the multi-ventilation and dynamicair-conditioning theory. The control strategies with a variety of energy cascadeutilization will meet the indoor comfort and air quality requirements at the same time.