125 YMCB Microclimate and Architecture 2 nd Lecture

Transcription

1 ČVUT v Praze Fakulta stavební Katedra technických zařízení budov 125 YMCB Microclimate and Architecture 2 nd Lecture prof. Ing. Karel Kabele, CSc. A227b kabele@fsv.cvut.cz PROBLEMS RELATED TO INDOOR ENVIRONMENTAL QUALITY 125 YMCB 2013/014 prof.karel Kabele 29 1

2 Indoor Environment and Health Sick Building Syndrome (SBS) set of symptoms and problems associated with users stay in a building without a clear cause Symptoms Complaints of discomfort, irritation of eyes, nose, headaches, fatigue, difficulty in concentrating; The cause is not known; Most problems disappear after leaving the building. 125 YMCB 2013/014 prof.karel Kabele 30 Indoor Environment and Health Building Related Illness (BRI) Diagnosed disease associated with stay in a building with a clear cause: occurrence of mold, gases concentration, Symptoms Users complain about the cold, stiff neck, fever, convulsions There are known causes - such as drafts, poor job Remedy usually lasts longer and the problems do not stop after leaving the building 125 YMCB 2013/014 prof.karel Kabele 31 2

3 Symptoms of SBS and BRI are identical to the most common health problems. Which of the following health problems you have had in the last 6 months? Top 10 health problems of CR population (%) Headache Running nose Cold Fatigue Cough Sore throat Flu Joint pain Back pain Insomnia 125 YMCB 2013/014 prof.karel Kabele 32 However, what is a healthy building: Experience with sick building syndrome 125 YMCB 2013/014 prof.karel Kabele 33 3

4 Truly healthy building 125 YMCB 2013/014 prof.karel Kabele 34 Factors of indoor climate with known quantitative effects on productivity Ventilation and sick leave Ventilation and work performance Perceived indoor air quality and task performance Temperature and work performance 125 YMCB 2013/014 prof.karel Kabele Rehva GB

5 Ventilation rates and sick leave 125 YMCB 2013/014 prof.karel Kabele Rehva GB 6 37 Temperature and performance Rehva GB YMCB 2013/014 prof.karel Kabele 38 5

6 Adaptation There may be defined three categories of adaptation to indoor climate (Folk 1974, 1981, Goldsmith 1974, Prosser 1958, Clark and Edholm 1985): 1. Behavioural Adjustment; 2. Physiological; 3. Psychological. Adjustment Behavioural /technological changes to the heat balance (clothing and activity, personal environmental control) Adaptation to Indoor Climate Habituation Psychological adaptation changing expectations (expectations and thermal memory, adaptive opportunity) Acclimatization Long term physiological adaptation to climate (genetic adaptation) The three components of adaptation to indoor climate (adapted from ASHRAE RP 884) 125 YMCB 2013/014 prof.karel Kabele 39 Heat - moisture Psychical Elmg field Indoor environment of buildings Air Lighting Acoustics HEAT MOISTURE IE THERMAL COMFORT 125 YMCB 2013/ prof.karel Kabele 6

7 Heat moisture microenvironment State of the internal environment in terms of heat and moisture flows between the human body and its surroundings... T a T p 125 YMCB 2013/ prof.karel Kabele Heat Exchange Between the Human Body and its Surroundings Metabolic heat M Heat transfer between the body and the - environment Q Respiration Convection Radiation Conduction Evaporation Convection Heat balance equation M = Q thermal comfort M > Q warm M < Q cold Radiation Conduction 125 YMCB 2013/ prof.karel Kabele 7

8 Factors Influencing Thermal Comfort Factors of Human Metabolic Heat Clothing Insulation Factors of Environment Air Temperature (Dry-Bulb) Relative Humidity Air Velocity Radiation (Mean Radiant Temperature) 125 YMCB 2013/014 prof.karel Kabele 56 Factors of Human - Metabolic Heat Basal Metabolism Metabolic Heat Muscle Metabolism 125 YMCB 2013/ prof.karel Kabele 8

9 Factors of Human - Metabolic Heat Unit 1 MET is defined as the production of energy of sitting person, when an adult consumes 3.4 ml respectively 3.6 milliliters of oxygen per kilogram of body weight per minute 1 Met = 58 W/m 2 0 up to 16,9 Met 125 YMCB 2013/014 prof.karel Kabele 58 Factors of Human - Metabolic Heat W/m Basal Metabolism x age, sex AGE MUŽI ŽENY Source: Jokl YMCB 2013/014 prof.karel Kabele 60 9

10 Factors of Human - Metabolic Heat Activity EN ISO 7730 Metabolic heat W/m 2 Lying 46 0,8 Relaxed Sitting 58 1,0 Work in a sitting position (offices, apartments, schools, laboratories) Standing, medium work (salesman, housework, work on machines) met 70 1,2 93 1,6 Jokl YMCB 2013/ prof.karel Kabele Metabolic Heat directly proportional to the surface of the human body Human body surface according to Du-Bois BSA = ( H 0,725 W 0,425 ) 0, BSA Body Surface Area cca 1,9 [m 2 ] W weight in kg, H hight in cm E.g.: 58 W/m 2 x 1,8 m 2 = 104 W 125 YMCB 2013/ prof.karel Kabele 10

11 I cl Factors of Human - Clothing Daily common clothing 0,3 panties, T-shirt, light socks, sandals 0,45 briefs, panties, stockings, light dresses with sleeves, sandals 0,5 pants, shirts with short sleeves, light trousers, light socks, shoes 0,6 pants, shirts, light pants, socks, shoes EN ISO ,7 underwear, shirts, pants, socks, shoes (panties, petticoat, stockings, dresses, shoes) Unit 1 clo=0,155m 2.K/W clo < 0,5 0,6-1,2 >3,5 125 YMCB 2013/ prof.karel Kabele Factors Influencing Thermal Comfort Factors of Human Metabolic Heat Clothing Insulation Factors of Environment Air Temperature Relative Humidity Air Velocity Radiation (Mean Radiant Temperature) 125 YMCB 2013/014 prof.karel Kabele 65 11

12 Factors of the Environment Air temperature State variable describing the kinetic energy of particles of the system. Thermodynamic /Kelvin/ T [K] Celsius t [ C] t= T-273,15 Fahrenheit [ F] 1 F=5/9 C ( F-32).5/9 = C The air temperature is without the influence of radiation, measured with a thermometer, protected from radiation heat source. 125 YMCB 2013/ prof.karel Kabele Factors of the Environment Mean Radiant Temperature MRT (also effective temperature of the surrounding surfaces, medium temperature of radiation) is defined as the uniform temperature of an imaginary enclosure in which the radiant heat transfer from the human body is equal to the radiant heat transfer in the actual non-uniform enclosure t r 1 n r1.t... rn.t 273 where tr = mean radiant temperature Ti = temperature of the surrounding surface i, i=1,2,...,n φ rn = shape factor which indicates the fraction of total radiant energy leaving the clothing surface 0 and arriving directly on surface i, i=1,2,...n 125 YMCB 2013/ prof.karel Kabele 12

13 Factors of the Environment Operative Temperature is defined as a uniform temperature of a radiantly black enclosure in which an occupant would exchange the same amount of heat by radiation plus convection as in the actual nonuniform environment. It can be defined as the average of the mean radiant and ambient air temperatures, weighted by their respective heat transfer coefficients. t o hct a h c hr t h r r Calculated value Where t op = operative temperature t a = air temperature t r = mean radiant temperature (MRT) h c = convective heat transfer coefficient h r = mean radiative heat transfer coefficient 125 YMCB 2013/ prof.karel Kabele Factors of the Environment Resultant Temperature (globe temperature) is measured with a globe thermometer, it includes the effect of air velocity and radiant heat source. to t g Naměření hodnota Valid for low air velocity (up to 0,2 m/s) and small differencies between t a and t r (up to 4 C), Jokl YMCB 2013/ prof.karel Kabele 13

14 Factors of the Environment Stereo temperature measured directional globe thermometer, includes the effect of air velocity and uniformity of radiant heat source Measured value Jokl,Jirák YMCB 2013/ prof.karel Kabele Measuring equipment 125 YMCB 2013/ prof.karel Kabele 14