Research On The Effect Of Indoor Environment Of Building On Comfort And Learning Performance

An increase in temperature and change of correlated color temperature(CCT)and sound type would affect cognitive performance and human physiology.The indoor environment has a great effect on health and comfort,which indirectly affects learning performance.Different environmental factors have different effects on comfort and learning performance,and the temperature of the thermal environment has the greatest impact.At present,the effect of sound type of the acoustic environment and CCT of the luminous environment on building comfort has not been clearly understood,and the interaction between multiple environmental factors has gradually become a hot research topic in the field of building comfort.Therefore,it has a theoretical basis and research prospect to study the effect of the interaction of multiple environmental factors on comfort and learning performance.The dependence on energy in modern architecture is more and more obvious.The HVAC(Heating,Ventilation and Air Conditioning)is the main energy consumption,which accounts for about 50% of the building energy consumption and 20% of the total energy consumption.If the indoor environment is only regulated through HVAC,the rate of thermal dissatisfaction expressed by users is still higher than 60%,which not only causes a huge waste of energy but also fails to provide a comfortable and satisfactory indoor environment for the user.The improvement of a particular environmental factor to bring about the synchronous change of other comfort has not been considered,which may be one of the reasons for the high thermal dissatisfaction rate under high energy consumption conditions.Therefore,it is of great financial implications to explore whether changing the acoustic and luminous environment in the building could alleviate the effect of thermal discomfort on users.In this thesis,in order to study the effects of acoustic and luminous environment on comfort and learning performance in different thermal environments,subjective questionnaires,cognitive test and physiological data of 20 subjects were collected under three CCT(3000K,4500 K and 6000K)and three temperatures(26℃,28℃ and 30℃),five sound types(classic,pop,fan,water and quiet)and two temperature(26℃ and 30℃).The subjective questionnaire was used to evaluate comfort,including thermal sensation and overall comfort.The N-Back cognitive test was used to measure learning efficiency and electrocardiogram(ECG)was used to reflect physiological state.The main results are as follows:(1)In terms of the effect of thermal and luminous environment on comfort,here are significant differences between CCT and thermal sensation index of comfort.When the temperature is 26℃,28℃,the CCT and thermal sensation is a significantly negative correlation,consistent with the “Hue-heat” hypothesis.When the temperature difference is 2℃,the comfort could be improved by changing the CCT,and the effect of temperature on thermal sensation could be reduced,thus reducing energy consumption.When the temperature difference is greater than 2℃,the effect of CCT on thermal sensation is weak,and the thermal sensation is mainly controlled by temperature.When the CCT difference reaches 3000 K,the CCT has a significant effect on the thermal sensation of the subjects at all three temperatures,and the higher CCT can make the thermal sensation of the subjects shift to the cold side.Therefore,it can be considered to increase the CCT within the acceptable temperature range to alleviate the influence of higher temperature on the thermal sensation of the subjects.(2)In terms of the influence of thermal and acoustic environment on comfort,there is a significant negative correlation between temperature and overall comfort,while the correlation between sound type and overall comfort is weak.When the temperature is26℃,creating an appropriate acoustic environment is helpful to improve the comfort of the indoor environment of the building,and the effect of classical music is better than that of pop music.When the temperature reaches 30℃,the overall comfort of the building decreases significantly,so the sound source should be rejected.A quiet environment is more in accord with the requirements for the building comfort,and the sound of the fan has the most negative impact on people.(3)HRV can be used as a potential physiological indicator to measure the comfort of the building’s indoor environment,including thermal sensation and overall comfort.When the thermal sensation is "neutral" and "slightly warm",the heart rate variability(HRV)is close to 1,and when the thermal sensation is "warm" and "hot",the HRV is greater than 2.When the overall comfort level is between "uncomfortable" and "slightly uncomfortable",there is an obvious downward trend,and the closer it is "comfortable",the closer the HRV is to 1.(4)There is no significant difference between the N-Back test score and the temperature,CCT and sound type in the indoor environment of the building.According to the arouse model,the short-term learning efficiency is less affected by temperature in the acceptable temperature range(26℃-30℃).Because of the complexity of learning process,whether HRV can be used as a potential evaluation index of learning efficiency needs to be further explored.Figure [25] table [16] reference [74]...