analysis of the influences of solar radiation and façade glazing ...

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4.2 Comments and conclusions 102 Apart from that, a reduction of the glazing area lead to a decrease in the operate temperature during the warm season, thus provided better thermal environment quality in living spaces. Furthermore, the analysis of the influence of the glazing system area on the buildings energy demands showed that there is a linear correlation, described by Eq. (3.1), between energy consumption for space heating and the window-to-wall ratio. � The next finding of this study was the determination of the relation between the energy transfer and the windows’ height above ground level for the warm season as well for the heating period – Eq. (3.2) and Eq. (3.3). Simulation results indicated that the difference between the first and the last floor is high and equal to 31 % for balcony-windows and up to 66 % for windows in winter month. The windows’ energy balance for the summer month showed that the difference between the first and the last floor is quite small due to the sun's higher elevation above the horizon. � The present work was also focused on the investigation of an intensive night ventilation system during the warm months when the ambient temperature is lower than inner air temperature. As it turned out, cooling by ambient air can be an energy-saving solution. This ventilation system, coupled with external shading devices, is sufficient to prevent living spaces from excessive overheating during the entire warm part of the year. It was found that the amplitude between day and night internal air temperatures is significantly higher for apartments with variable air volume systems. Due to this effect, we can relatively quickly reduce and stabilize the air temperature to a lower level inside living spaces. The difference between the operate temperature in apartments with constant air volume systems and with night cooling systems using the variable air volume flow increases from April to the first half of June. This value stays approximately at the same level equal to 3.5°C for the next period of the warm season. The maximum value differs from 4.1°C to 4.4°C and the mean value differs from 2.7°C to 3.0°C depending on the apartment location. � Based on the results of the multivariate testing of the buildings’ energy performance and thermal comfort conditions for warm seasons, we are allowed to state that the window shade with the highest reflection surface mounted outside and near the fenestration guarantees the best protection of gains from solar radiation. � The results indicate that if we change the collector tilt angle from 25° to 60°, the absorbed solar energy varies only about 10 % in the period of a year. However, applying the extreme angles 0° (a horizontal position) and 90° (a vertical position) leads to a significant reduction of the DHW systems efficiency. Energy conversion decreases to 70 % of the maximal value in an optimal panel position for the angle 0° and for the angle 90° the same reduction reaches about 50 %. Simulation results
4.3 Future research 103 of the annual operation of the solar domestic hot water system revealed that the best solar collector tilt angle is 70° for the cold period and 35° for summer time. If the tilt angel is fixed, the best thermal performance can be obtained at an angle of 45°. It turned out that the solar conversion process is about ten times lower in winter than those during the summer time. Based on the analysis of the influence of the volume of accumulated water on the thermal performance of the solar DHW system, it can be concluded that the recommended volume of the storage tank for the developed case is 4 m 3 . Moreover, it was shown how the increase of system thermal capacity leads to the prolonging of the storage tank operating period with raised output temperature and a simplified description of this physical process was proposed. Results of the calculations showed that the temperature of storage water increased over 50°C only between April and September. We can conclude that the total designed area of solar collectors is too small to support the heating system. � It is suggested to use the following equivalent parameters of Poroton-T9 in the calculations: heat capacity equal to 855,1 J/kgK, heat conductivity equal to 0,09 W/mK and unit weight equal to 653,15 kg/m 3 . 4.3 Future research The future work within the VASATI 2.0 project will be focused on: � design and practical application of a building performance monitoring system, � further experimental investigations of the thermal performance of complete external walls and the estimation of real energy consumption when the co-operative apartment buildings are occupied in order to verify the results of selected estimations presented in this dissertation.
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ANALYSIS OF THE INFLUENCES OF SOLAR
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than the inner air temperature. It
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4.1 SUMMARY .......................
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Subscripts σ - Stefan-Boltzmann co
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1.1 Introduction 9 Another problem,
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1.2 Background and literature revie
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2.1 Building energy simulation soft
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2.2 Experimental research methods 4
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2.2 Experimental research methods 4
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Page 53 and 54: 3.1 Building description 53 Fig. 3.
Page 55 and 56: 3.1 Building description 55 All int
Page 57 and 58: 3.1 Building description 57 Case B5
Page 59 and 60: 3.1 Building description 59 Of cour
Page 61 and 62: 3.1 Building description 61 Outside
Page 63 and 64: 3.1 Building description 63 In orde
Page 69 and 70: 3.2 Selection of the optimal glazin
Page 71 and 72: 3.3 Estimation of thermal energy ga
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Page 99 and 100: 4.1 Summary 99 4 Summary and conclu
Page 101: 4.2 Comments and conclusions 101 So
Page 105 and 106: References 105 Beausoleil-Morrison,
Page 107 and 108: References 107 Hendron, R., et al.
Page 109 and 110: References 109 Rees, S. and Haves,
Page 111 and 112: References 111 Yohanis, Y.G., et al
Page 113 and 114: Appendix 1 113 Fig. A1.1 VASATI 2.0
Page 123 and 124: Appendix 2 123 !-Generator IDFEdito
Page 125 and 126: Appendix 2 125 0.035, !- Conductivi
Page 127 and 128: Appendix 2 127 , !- Zone Inside Con
Page 129 and 130: Appendix 2 129 Discrete; !- Numeric
Page 131 and 132: Appendix 2 131 Fraction, !- Schedul
Page 133 and 134: Appendix 2 133 Air Conditioner:Wind
Page 135 and 136: Appendix 2 135 , !- Sensible Heat F
Page 137 and 138: Appendix 2 137 281, !- Lighting Lev
Page 139 and 140: Appendix 2 139 OG2 InfilTRATION, !-
Page 141 and 142: Appendix 2 141 OG3, !- Zone Name 16
Page 143 and 144: Appendix 2 143 0.004, !- Zone Heati
Page 145 and 146: Appendix 2 145 Zone15WindACAirInlet
Page 147 and 148: Appendix 2 147 0, !- Maximum Flow R
Page 149 and 150: Appendix 2 149 Zone16WindACOAMixer,
Page 151 and 152: Appendix 2 151 Zone 9 Outlet Node;
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Appendix 2 153 Stand Alone ERV 16,
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Appendix 2 155 ZoneHVAC:WindowAirCo
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Appendix 2 157 ZoneHVAC:Baseboard:C
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Appendix 2 159 Zone Control Type Sc
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Appendix 2 161 WindACPLFFPLR, !- Pa
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Appendix 2 163 Stand Alone ERV Supp
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Appendix 2 165 0.03001, !- Maximum
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Appendix 2 167 0.81, !- Sensible Ef
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Appendix 2 169 !- == ALL OBJECTS IN
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