**4. Model assumptions and development**

The picture of the experimental setup in a prefabricated outdoor room is presented in **Figure 3**. The solar noon annual solstices and equinoxes days are selected for performing sensitivity analysis to achieve range of: (i) temperatures of pre-conditioned fresh air available; (ii) electric power generation vis-à-vis surface temperatures of photovoltaic modules; (iii) integrated noise insulation values due to noise fields of composite wave elements transmitted into the room. Computer aided simulation model is developed for an airflow window system located in Montréal. Some examples of noise insulation calculations are illustrated using newly devised noise measurement equations for noise of sol, noise of therm, noise of scattering

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels DOI: http://dx.doi.org/10.5772/intechopen.93296*

**Figure 3.** *Prefabricated outdoor room at Concordia University.*

*Noise and Environment*

noise;

gives positive values of noise;

gives negative values of noise.

**3.2 Noise reduction coefficients**

author [1–60].

i.Each unit of sol, sip and bel is divided into 11 parts, 1 part is 1/11th unit of

ii.The base of logarithm used in noise measurement equations is 11.

Reference value of I2 is −1 W m−2 with I1 on positive scale of noise, should be taken with negative noise measurement expression (see Eqs. 3, 5 and 7), therefore it

Reference value of I2 is 1 W m−2 with I1 on negative scale of noise, should be taken with positive noise measurement expression (see Eqs. 3, 5 and 7), therefore it

uct and system of noise scales and their units distinguished from prevailing *decibel* units (which have its limitations) in the International System of Units. More discussions on energy conversion, noise characterization theory and choice of noise scales and its units are presented in many papers by the

where ΔoS is noise of therm reduction (noise transmission loss) in oncisol.

where ΔoSi is noise of scattering reduction (noise transmission loss) in oncisip.

where ΔoB is noise of elasticity reduction (noise transmission loss) in oncibel.

The picture of the experimental setup in a prefabricated outdoor room is presented in **Figure 3**. The solar noon annual solstices and equinoxes days are selected for performing sensitivity analysis to achieve range of: (i) temperatures of pre-conditioned fresh air available; (ii) electric power generation vis-à-vis surface temperatures of photovoltaic modules; (iii) integrated noise insulation values due to noise fields of composite wave elements transmitted into the room. Computer aided simulation model is developed for an airflow window system located in Montréal. Some examples of noise insulation calculations are illustrated using newly devised noise measurement equations for noise of sol, noise of therm, noise of scattering

Noise reduction coefficient for noise of sol (thermal power):

Noise reduction coefficient for noise of sip (fluid power):

Noise reduction coefficient for noise of bel (sound power)

**4. Model assumptions and development**

The choosing of *onci* in noise units is done so as to have separate market prod-

−∆ = − oS/22 NRC 1 11 (8)

−∆ = − oSi/22 NRC 1 11 (9)

−∆ = − oB/22 NRC 1 11 (10)

**114**

and noise of elasticity. The sensitivity analysis for an outdoor duct is also conducted for critical design of ventilation requirements with supply of varying outdoor mass flow rate to a single building zone. The improved method is useful for accurately predicting ventilation air requirements along with designing integrated thermal and sound insulation through a double or cavity wall building structure.

**Table 3** has provided properties of physical domain. **Tables 4**–**10** have presented sensitivity analysis and noise characterization values for the exterior duct based on mass flow rate, solar irradiation and size of duct. The thermal modeling results are presented in **Figures 4**–**8**. **Figure 4** has presented efficiencies of the building integrated photovoltaic airflow window system viz., electrical efficiency of PV module and combined efficiency of the system. **Figure 5** has presented thermal model results of PV Module, insulation panel and air with respect to height of the spandrel section. **Figure 6** has presented thermal model results for PV module temperatures with solar time for forced and natural convection and air temperatures for forced and natural convection for air cavities I and II. **Figure 7** has results for useful energy generated and solar energy absorbed by a photovoltaic module. **Figure 8** has provided variation of hydraulic diameter, velocity and flow rate vs. pressure drop on a log scale.

The thermo-physical properties of photovoltaic modules, air and insulating panel were assumed constant along all directions i.e. x-, y-, and z-ordinates. The thermo-physical properties of insulating panel with building insulation were obtained from tests conducted with heat flow meter and related specifications from the manufacturer [3]. The temperature differences along x-direction are obtained by assuming same temperature difference per unit thickness of material along x- and y-ordinates [3]. The heat storage capacity for temperature differences across x-direction is negligible of the heat storage capacity for temperature differences across y-direction. Therefore temperatures are assumed uniform and lumped in x-direction. The pair of glass coated photovoltaic modules was having three layers of material viz., a flat sheet of solar cells, with glass face sheets on its exterior and interior sides. The measurements were collected for a pair of successive runs at same solar intensities [3]. The thermal model is validated by comparing its predicted results with those obtained from the experimental apparatus. The agreement between the predictions of the thermal model and experimental results was presented to be very good [3].


#### **Table 3.**

*Properties of physical domain.*


#### **Table 4.**

*Temperature difference and noise of sol with solar irradiation (air velocity: 0.75 ms−1).*


**117**

**Table 10.**

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels*

**Noise of therm oS (oncisol)**

**Noise of scattering oS (oncisip)**

*Noise of elasticity with air particle velocity (impedance Z0 = 413 N·s·m−3 at 20°C).*

**s −1)—room**

*Thermo-fluid noise transmission loss and noise reduction coefficient.*

*Acoustic noise transmission loss and noise reduction coefficient.*

*Fluid noise transmission loss and noise reduction coefficient.*

**Mass flow rate (kg** 

15.50 0.01376 71.09 19.5602 15.28 0.0231 117.65 21.868 18.90 0.01275 80.325 20.119 18.22 0.0171 103.85 21.296 22.40 0.0120 89.6 20.614 22.40 0.0120 89.6 20.614 25.90 0.0115 99.2833 21.043 28.15 8.1 × 10−3 76.0 19.866 29.40 0.0111 108.78 21.505 29.80 6.2 × 10−3 61.59 18.898

> **Sound pressure (N·m−2)**

**Noise of therm oS (oncisol) room**

21.868 25 0.02095 28.721 6.853 0.52619

**Noise of elasticity oB (oncibel)—room v = 0.15 m·s−1**

**Noise of scattering oS (oncisip)—room v = 0.15 m·s−1**

24.97 9.29 15.68 0.81896

15.02 7.64 7.38 0.55264

1.35 47.62 17.72 557.5 752.7 30.36 1.05 37.0 16.50 433.65 455.33 28.05 0.75 26.45 15.02 309.75 232.31 24.97 0.45 15.87 12.65 185.85 83.63 20.24 0.15 05.29 07.64 61.94 09.29 10.12

**(ΔT) °C Mass** 

**flow rate (kg s−1)**

> **Sound power intensity (W·m−2)**

> > **Transmission loss ΔoS (oncisol)**

**Transmission loss ΔoB (oncibel)**

**Transmission loss ΔoS (oncisip)**

**Thermal power (Wm−2)**

**Noise of therm oS (oncisol)**

**Noise of elasticity oB (oncibel)**

> **Noise reduction coefficient**

**Noise reduction coefficient**

**Noise reduction coefficient**

*DOI: http://dx.doi.org/10.5772/intechopen.93296*

**Thermal power (Wm−2)**

**flow rate (kg s−1)**

*Mass flow rate and noise of therm with (ΔT) °C.*

**Fluid power (W·m−2)**

> **(ΔT) °C room**

**(ΔT) °C Mass** 

**Table 6.**

**Air velocity (m·s−1)**

**Table 7.**

**oS (oncisol) duct**

**Table 8.**

**Table 9.**

**Noise of therm** 

**Noise of elasticity oB (oncibel)—duct v = 0.75 m·s−1**

**Noise of scattering oS (oncisip)—duct v = 0.75 m·s−1**

#### **Table 5.**

*Temperature difference and noise of scattering with air velocity (S = 650 Wm−2).*


*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels DOI: http://dx.doi.org/10.5772/intechopen.93296*

#### **Table 6.**

*Noise and Environment*

Ambient heat transfer

coefficient

Ambient air temperature

Building space temperature

Thickness of outer wall of duct

Absorptance of outer wall with flat black

Thermal conductivity of aluminum alloy for HVAC duct

*Properties of physical domain.*

RSI value 1.0 m2

paint

**116**

**Table 5.**

**Air velocity (ms−1)**

**Table 4.**

**Table 3.**

**Fluid power (Wm−2)**

*Temperature difference and noise of sol with solar irradiation (air velocity: 0.75 ms−1).*

*Temperature difference and noise of scattering with air velocity (S = 650 Wm−2).*

**Air temperature difference (ΔT) °C**

1.35 47.62 15.28 17.72 1.05 37.0 18.22 16.50 0.75 26.45 22.40 15.02 0.45 15.87 28.15 12.65 0.15 05.29 29.80 07.64

**Solar irradiation (Wm−2) Air temperature difference (ΔT) °C Noise of sol oS (oncisol)**

450 15.50 28 18.90 28.93 22.40 29.7 25.90 30.36 29.40 30.91

**Property Value Property Value** Solar irradiation 650 W m−2 Width of air gap 0.025 m

Width of duct 1.0 m Prandtl number of air 0.708

0.0025 m Air velocity for

0.95 Stefan Boltzmann

K W−1 Number of nodes in x

137 W m−1 K −1 Emissivity of back

Height of duct 3.0 m Kinematic viscosity

Thickness 0.04 m Number of nodes in y

13.5 W m−2 K−1 Thermal conductivity

−5°C Specific heat of air

of air

(Cp)

of air

obtaining mass flow rate

constant for surface of duct walls

surface of duct walls

direction

direction

20°C Density of air 1.1174 kg m−3

**Noise of scattering oS (oncisip)**

0.02624 W m−1 K−1

1000 J kg−1 K−1

15.69 × 10−6 m2

0.75 m s−1

5.67 × 10−8 W m−2 K−4

0.95

Nx = 3

Ny = 10, Δy = 0.3 m

s−1

*Mass flow rate and noise of therm with (ΔT) °C.*


#### **Table 7.**

*Noise of elasticity with air particle velocity (impedance Z0 = 413 N·s·m−3 at 20°C).*


#### **Table 8.**

*Thermo-fluid noise transmission loss and noise reduction coefficient.*


#### **Table 9.**

*Acoustic noise transmission loss and noise reduction coefficient.*


#### **Table 10.**

*Fluid noise transmission loss and noise reduction coefficient.*

**Figure 4.** *Efficiencies: (a) electrical efficiency of PV module and (b) combined efficiency of the system.*

**119**

**Figure 7.**

**Figure 6.**

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels*

*Thermal model results: (a) PV module temperatures and (b) air temperatures.*

*Useful energy generated and solar energy absorbed by a photovoltaic module.*

*DOI: http://dx.doi.org/10.5772/intechopen.93296*

**Figure 5.** *Thermal model results: (a) PV module, (b) insulation panel, and (c) air.*

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels DOI: http://dx.doi.org/10.5772/intechopen.93296*

**Figure 7.** *Useful energy generated and solar energy absorbed by a photovoltaic module.*

*Noise and Environment*

**118**

**Figure 5.**

**Figure 4.**

*Efficiencies: (a) electrical efficiency of PV module and (b) combined efficiency of the system.*

*Thermal model results: (a) PV module, (b) insulation panel, and (c) air.*

**Figure 8.** *Variation of (a) hydraulic diameter, (b) velocity, and (c) flow rate vs. pressure drop on a log scale.*

### **5. Conclusion**

A study on integrated insulation modeling of an airflow window with a PV solar wall via energy conversion is performed. The noise interference and characterization equations as per speed of a composite wave are presented. The sources of noise measurement equations (sun, light, sound, heat, electricity, fluid and fire) are described depending on their speed of noise interference. Noise measurement equations and their units are coined. The acoustic insulation systems are classified as per source signals of solar power, electric power, light power, sound power, heat power, fluid power and fire power. Based on sensitivity analysis conducted on an outdoor duct exposed to solar radiation, integrated insulation model has calculated noise transmission losses and noise reduction coefficients, besides calculating individual values of oncisol, oncisip and oncibel for various types of noises.

Several performance and optimization issues are considered in development of the model including optimal air velocity for heat transfer, dimensions of PV

**121**

**Author details**

**Acknowledgements**

Himanshu Dehra

Monarchy of Concordia, India

provided the original work is properly cited.

\*Address all correspondence to: anshu\_dehra@hotmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels*

module (height), selection of cavity width to reduce pressure drops, and prediction of temperature rise of air as it flows out of the airflow window system and into the outdoor test-room. The airflow is adjusted to a constant value to optimize necessary temperature for integrated photovoltaic array as well as for pre-heated fresh air into the outdoor test-room. It is envisaged that inside an airflow window integrated with PV, cooling by forced convection is essential, without which, the temperature of PV cell reaches very high (51°C), which decreases the efficiency by more than 20% [4]. The combined efficiency (electrical and thermal) of the system reaches 50%. A building integrated photovoltaic airflow window (BIPV-AW) system is developed for the purpose of combined generation of electricity, thermal energy and daylighting. This approach will have additional following advantages: (a) there will be reduction in peak heating loads, which will reduce the required capacity of the heating/cooling system; (b) there will be reduction in energy consumed for heating and lighting in the building; and (c) electricity demand of the building will

The author conducted part of the work at Department of Building, Civil and Environmental Engineering, Concordia University, Montréal, Québec, Canada.

*DOI: http://dx.doi.org/10.5772/intechopen.93296*

be reduced and energy utilities will get peak surplus.

*Noise Transmission Losses in Integrated Acoustic and Thermo-Fluid Insulation Panels DOI: http://dx.doi.org/10.5772/intechopen.93296*

module (height), selection of cavity width to reduce pressure drops, and prediction of temperature rise of air as it flows out of the airflow window system and into the outdoor test-room. The airflow is adjusted to a constant value to optimize necessary temperature for integrated photovoltaic array as well as for pre-heated fresh air into the outdoor test-room. It is envisaged that inside an airflow window integrated with PV, cooling by forced convection is essential, without which, the temperature of PV cell reaches very high (51°C), which decreases the efficiency by more than 20% [4]. The combined efficiency (electrical and thermal) of the system reaches 50%.

A building integrated photovoltaic airflow window (BIPV-AW) system is developed for the purpose of combined generation of electricity, thermal energy and daylighting. This approach will have additional following advantages: (a) there will be reduction in peak heating loads, which will reduce the required capacity of the heating/cooling system; (b) there will be reduction in energy consumed for heating and lighting in the building; and (c) electricity demand of the building will be reduced and energy utilities will get peak surplus.
