Research On Environmental Control Strategy Of Residential Bathroom Based On Human Thermophysiological Changes

Although the bathing room is an auxiliary space for residential buildings,bathing behavior around bathing rooms has important influence on the thermo-physiological health of the occupants.The bathing process is dynamic and continuous,and the human body is influenced of by environmental factors such as hot water,thermal radiation,and air flow,and the posture of bathing when naked.Therefore,bathing person is in an nonuniform,dynamic and changing thermal environment.In their home life,the adaptability of the elderly to the environment is reduced and their dependence is enhanced.The inappropriate thermal environment of bathing rooms and bathing behavior are likely to cause thermo-physiological changes in the elderly,and induce sudden onset of dizzy,cerebral infarction and falls.In this paper,the thermo-physiological changes of the elderly during bathing are taken as the research contents.From the angle of human body temperature and blood pressure changes,the thermal environment of the bathroom is analyzed and studied.The characteristics and manner of the temperature and blood pressure changes during the bathing process were clearly defined.A comprehensive analysis and assessment of the environmental causes and influencing mechanisms of temperature and blood pressure changes were made,and the corresponding control strategies for the thermal environment of bathing rooms were put forward.First,through literature review and field investigation,the research on the bathing room in hot summer and cold winter was conducted,and the thermal environment of the bathroom was clarified.The environmental factors and personal factors that may lead to the changes of body thermo-physiology are summarized.Secondly,field bathing experiments are carried out in the surveyed area,with emphasis on monitoring the changes of physiological parameters such as temperature and blood pressure under different conditions.The monitoring results are used to verify the model,and the thermal environment data are used as model boundary conditions at the same time.Thirdly,based on a thermo-physiological model using the negative feedback regulation mechanism proposed by Stowljik et al.,a multi node numerical heat transfer model for predicting human skin temperature and body temperature under non-uniform unsteady state environment was developed.In combination with a cardiovascular control model based on the relationship between blood pressure and vasodilatation,which is driven by human body temperature changes and was proposed by Yoshioka and Hokoi,a new human body temperature and blood pressure coupling prediction model was developed.Finally,the thermo-physiological changes in a human body under various bathing conditions are predicted.The quantitative relationship between the thermal environment of bathing rooms and the changes of body temperature and cardiovascular system was analyzed and evaluated,and the time profiles of human body temperature and blood pressure under different working conditions were obtained.The influence of air temperature and hot water temperature on the body temperature and blood pressure were compared and analyzed.The temperature calculated by the proposed model agreed with the measured result within±0.2 degrees.The prediction accuracy of the human body temperature change rate is ±0.01 degrees centigrade/minute.The temperature model could accurately reproduce the temperature changes of each node in the body.The cardiovascular model could reasonably reflect the trend of blood pressure change.Based on the simulation results,the setting up the front room of the shower room was recommended and quantifying the relevant environmental factors during bathing was put forward.To clarify the mechanism of human body’s thermal and physiological changes in bathing room is an urgent need to avoid accidents in residential bathing rooms,and also conducive to healthy and intelligent residential design in the future.The prediction model of human thermal physiology under non-uniform and unsteady conditions can be also a useful tool and scientific basis for developing other protective measures,which is conducive to the design,renovation and evaluation of healthy thermal environment.The simulation of human body temperature based on the negative feedback regulation mechanism is widely used in the fields of aerospace and special operations.However,there are few physiological and psychological assessments in daily life.At the same time,the temperature change as a driving force predicts the cardiovascular regulation in practical conditions.It will help and support the research and practice of building thermal environment based on human health conditions.Words: 72471;Figures and Tables: 133.