Assignability of Thermal Comfort Models to nonstandard

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1 Department of Architecture Institute of Building Climatology Assignability of Thermal Comfort Models to nonstandard Occupants P. Freudenberg Dresden,

2 Thermal Comfort Models: Motivation Objectives of thermal comfort models: Prediction of thermal comfort and its effects on productivity, healing processes and other aspects Based on these predictions/models: optimization of buildings and/or HVAC- system operation What s the definition of thermal comfort? ASHRAE, ISO- Definition: [ ] condition of mind which expresses satisfaction with the thermal environment. Thermal sensation very subjective Dependence on individual physiology (constitution, age, ) Dependence on individual psychology (mood, experiences, ) Comfort Model Adaption Slide No. 2 of 15

3 Thermal Comfort Models: Basic Parameters Physiological Aspects Aspects of Behavior, Psychology Respiration sensible Food- and drinkintake Adaption Respiration latent Metabolic heat generation Radiation Exchange Sweating Convection Diffusion Conduction Actual and previous zone and outdoor conditions: air and radiant temperature, air velocity, relative humidity, Comfort Model Adaption Slide No. 3 of 15

4 Comfort Models Types Physiological Aspects: Static Models People are passive receptors of thermal conditions Thermal comfort can be predicted by the help of heat balance results Surveys are needed to correlate heat balance results with subjective comfort sensation Example authors: DeDear, Brager, McCarthy, Nicol, Humphreys Further Aspects: Adaptive Models People are active manipulators of thermal conditions Thermal sensation depends strongly on outside weather conditions Surveys are needed to correlate tolerance range with outside weather conditions Example authors: Fanger, Gagge, Stollwijk, Azer, Hsu Comfort Model Adaption Slide No. 4 of 15

5 Static Models: Principle Fanger Heat Balance L = QMet QRe s,s QRe s,l QDiff QSweat QRad QConv L;M Q Res,S Q Res,L Q Sweat Q Conv Q met Q Rad Q Diff Indoor climate conditions Person Properties ϑzoneair; ϑzonerad; ϕzoneair;v ZoneAir I CL;M PMV = L e Q Met ABody Comfort Model Adaption Slide No. 5 of 15

6 Adaptive Models: Principle DeDear/ Brager Approach θ e (t) Adaption immediate and long- time adaption of behavior Physical adaption (acclimatization) Psychological adaption (experiences) θ = θ Comf Average,month Climate conditions (Adaption supposed) Person Properties: (Adaption supposed) ϑzoneair; ϑzonerad; ϕzoneair;v ZoneAir I CL;M Comfort Model Adaption Slide No. 6 of 15

7 Application Case: Patients General conclusions: Limitation of physical adaption (e.g. change of location in zone, adaption of clothing, adaption of activity) Non- standard physical properties (e.g. due to age, constitution, state of health, disabilities, ) Adaptive Models definitely not applicable Application of Static Models should be proved (data implementation and results verification) Comfort Model Adaption Slide No. 7 of 15

8 Application Case: Data Implementation Bedding System Insulation Equations for bed- clothing combinations available, e.g. McCullough 1993 Metabolic Activity (Reduced for bed-ridden patients) Field study results for different building types available, e.g. Verheyen 2011 (patient activities) Influence of Age (Child, Adults, Elderly) Variations in core and skin temperature, sweat secretion rates, metabolic activity for defined age ranges, e.g. Tsuzuki-Hayakawa 1995 (properties of children) Medication (e.g. Morphine, Tranquillizer) Implementation not possible because of multiple medication and contrary effects Disabilities Marginal differences, implementation not necessary (Web & Parsons 1999) Comfort Model Adaption Slide No. 8 of 15

9 Application Case: Input Data Type w body h body θ n,core θ n,skin Q met I clo g Sweat [kg] [cm] [ C] [ C] [W/m²] [ m²k/w] [g/hm²] Child, laying, covered Adult, laying, covered Elderly, laying, sl.cov Elderly, laying, cov Adult, standing Adult, working Comfort Model Adaption Slide No. 9 of 15

Fanger, Steady- State Static Model Q Res,S Q Res,L PMV = L 0.352 e Q Met 0.042 + 0.

10 Fanger, Steady- State Static Model Q Res,S Q Res,L PMV = L e Q Met ABody Q Sweat Q Conv Q met C body = 0 Q Rad Q Diff L Body (Q met, Q sweat, Q Diff, Q Rad,Q Conv, Q Res,L,Q Res,S ) Comfort Model Adaption Slide No. 10 of 15

11 Gagge, Stollwijk-PMV*- Transient Static Model Q Res,S ( ) PMV = L θ e ET Q Met ABody Q Res,L Q Sweat C Skin ( ) PMV = L θ e SET Q Met ABody Q Conv Q met Q Ex,Blood C Core Q Ex,Blood QEx,Cond Q Rad Q Diff L Core (Q met, Q sweat, Q Diff, Q Rad,Q Ex,Cond, Q Ex,Blood ) L Skin (Q Res,L,Q Res,S, Q Ex,Cond, Q Ex,Blood ) Comfort Model Adaption Slide No. 11 of 15

Azer/ Hsu- TSV- Transient Static Model Q Res,S Q Res,L TSV = ε + ε ε 1.46 3.75 6.19 2 3 Vasoc Vasoc Vasoc TSV = ϕ ε + 5.0 5.56 ( 0.

12 Azer/ Hsu- TSV- Transient Static Model Q Res,S Q Res,L TSV = ε + ε ε Vasoc Vasoc Vasoc TSV = ϕ ε ( 0.5) Sweat Q Sweat C Skin C Core Q Conv Q met Q Ex Q Diff Q Rad L Core (Q met, Q sweat, Q Diff, Q Rad,Q Ex ) L Skin (Q Res,L,Q Res,S, Q Ex ) Comfort Model Adaption Slide No. 12 of 15

13 Calculation vrs. Field Studies Type θ Opt,Fanger θ Opt,GaggeET θ Opt,GaggeSET θ Opt,AzerHsu [ C] [ C] [ C] [ C] Child, laying, covered * 21.9 Adult, laying, covered * 22.1 Elderly, laying, sl.cov. -* * 24.5 Elderly, laying, cov. -* * 23.5 Adult, standing * 26.1 Adult, working Predicted Comfort (Calculation) *simulated values exceed or fall below C (temperature range of evaluation period) Type Source θ Opt,Requested [ C] Adult Patient Smith & Rae 1977, England Adult Patient Skoog et al. 2005, Sweden 22.4 Requested Comfort (Field Studies) Adult Patient Hwang et al. 2007, Taiwan 24.0 Adult Patient Khodakarami & Knight, 2008, Iran Adult, working Yau & Chew, 2009, Malaysia Comfort Model Adaption Slide No. 13 of 15

14 Conclusion Prediction of thermal comfort can be performed via adaptive and static models, both models are limited For particular occupant properties or/and limited physical or psychological adaption: only static models are appropriate Static comfort models allow implementation of occupant properties like neutral core and skin temperatures, weight, size,. Two of these static comfort models produce realistic results for the chosen application case of patients: Gagge- PMV (ET) and Azer-Hsu TSV Comfort Model Adaption Slide No. 14 of 15

15 Thank you for your attention! Comfort Model Adaption Slide No. 15 of 15

Environmental Engineering

Environmental Engineering 1 Indoor Environment and Thermal Comfort Vladimír Zmrhal (room no. 814) Master degree course 1 st semester (winter) Dpt. of Environmental Engineering 1 Environmental Engineering