船舶空调舱室热舒适性是影响船员工作效率和生活品质的重要因素。文章分析了影响空调舱室热舒适性的诸多因素,讨论了PMV(Predicted Mean Vote预测平均满意值)指标的作用及其运算方法,建立了舱室简化模型,并结合实际海况,计算了不同温度...船舶空调舱室热舒适性是影响船员工作效率和生活品质的重要因素。文章分析了影响空调舱室热舒适性的诸多因素,讨论了PMV(Predicted Mean Vote预测平均满意值)指标的作用及其运算方法,建立了舱室简化模型,并结合实际海况,计算了不同温度、相对湿度组合下的PMV、PPD(Predicted Percentage of Dissatisfied,预测不满意率)值及系统热负荷,分析了舱室内温度、相对湿度对其热舒适性及能耗的影响。在满足热舒适性指标的情况下,优化船舶空调设计参数以实现节能的目的。对船舶空调的设计及舱室温微气候参数的选择具有借鉴意义。展开更多
International standards state the thermal comfort requirements that office spaces must comply with. These are based on a model developed by Prof. Paul Ole Fanger of the Centre for Indoor Environment and Energy, Denmar...International standards state the thermal comfort requirements that office spaces must comply with. These are based on a model developed by Prof. Paul Ole Fanger of the Centre for Indoor Environment and Energy, Denmark. Today, forty-year research shows an evolution in these experiences. The work presented here is to develop a tool to evaluate the thermal comfort of working environments of office buildings. A methodology is devised on the basis of on-site measurements and questionnaire responses. For measurements, a mobile unit equipped with sensors is used, whereas the questionnaire obtains user responses on thermal quality of the work space. The thermal conditions of thirty office buildings presenting different acclimatization systems have been surveyed. The correlation between objective and subjective data allows developing a formula that shows the thermal comfort level for a given environment as a function of local aspects. For the surveyed buildings, the resulting comfortable temperature was 23.3℃, and the minimum percentage of user individuals experiencing discomfort with such temperature was 7%.展开更多
When temperature of paraffinic mineral oil base stocks is decreased belowcloud point,waxy hydrocarbonscome out of solution and growinto plates and needles wax crystalsforming a three-di mensional networkthat totallyi ...When temperature of paraffinic mineral oil base stocks is decreased belowcloud point,waxy hydrocarbonscome out of solution and growinto plates and needles wax crystalsforming a three-di mensional networkthat totallyi m-mobilizes the oil.Addition of a properlyselected PPD will provide a verylarge enhancement of low-temperature perfor-mance of the oil at verylowconcentrations.Howtoselect a right PPDfor your formulations are discussedinthis paper.展开更多
文摘船舶空调舱室热舒适性是影响船员工作效率和生活品质的重要因素。文章分析了影响空调舱室热舒适性的诸多因素,讨论了PMV(Predicted Mean Vote预测平均满意值)指标的作用及其运算方法,建立了舱室简化模型,并结合实际海况,计算了不同温度、相对湿度组合下的PMV、PPD(Predicted Percentage of Dissatisfied,预测不满意率)值及系统热负荷,分析了舱室内温度、相对湿度对其热舒适性及能耗的影响。在满足热舒适性指标的情况下,优化船舶空调设计参数以实现节能的目的。对船舶空调的设计及舱室温微气候参数的选择具有借鉴意义。
文摘International standards state the thermal comfort requirements that office spaces must comply with. These are based on a model developed by Prof. Paul Ole Fanger of the Centre for Indoor Environment and Energy, Denmark. Today, forty-year research shows an evolution in these experiences. The work presented here is to develop a tool to evaluate the thermal comfort of working environments of office buildings. A methodology is devised on the basis of on-site measurements and questionnaire responses. For measurements, a mobile unit equipped with sensors is used, whereas the questionnaire obtains user responses on thermal quality of the work space. The thermal conditions of thirty office buildings presenting different acclimatization systems have been surveyed. The correlation between objective and subjective data allows developing a formula that shows the thermal comfort level for a given environment as a function of local aspects. For the surveyed buildings, the resulting comfortable temperature was 23.3℃, and the minimum percentage of user individuals experiencing discomfort with such temperature was 7%.
文摘When temperature of paraffinic mineral oil base stocks is decreased belowcloud point,waxy hydrocarbonscome out of solution and growinto plates and needles wax crystalsforming a three-di mensional networkthat totallyi m-mobilizes the oil.Addition of a properlyselected PPD will provide a verylarge enhancement of low-temperature perfor-mance of the oil at verylowconcentrations.Howtoselect a right PPDfor your formulations are discussedinthis paper.
