STUDIES

4.3 SPOT MEASUREMENTS

4.3.1 Temperature

| COMPUTER LAB 01

Temperature spot measurements were taken of the computer lab-1 on October 26th, 2021, at 3 different times of the day, namely at 9:00 am, 2:00 pm, and 6:00 pm under clear, cloudy, and partly cloudy sky conditions by 16 Morwell street. The sunset by 6:30 pm. The results are depicted in Fig.4.3.1.1, Fig. 4.3.1.2 and Fig 4.3.1.3 The shown temperature ranges between 220C to 250C throughout the day at various spots due to the space being mechanically controlled by a central HVAC system.

According to the IT lab staff, the thermostat is set to a temperature of 220C throughout the day. The rise in temperature above this set value is due to heat generated from the computers and occupants in the space.

To begin with, the temperature in the computer lab with 5 occupants at 9.00 AM was registered at an average of 22.5°C, while the outdoor temperature which was registered on Morwell Street adjacent to the lab was 13°C. Thus, an 9K difference can be identified between the outdoor temperature and that of the computer lab. Similarly, the temperature recorded at 2.00 PM with 9 occupants provided similar results with the indoor temperature being an average of 22.5°C though the outdoor temperature was 18°C on Morwell Street. The fact that the thermostat’s set temperature controls the space, affected the recorded indoor value.

On the other hand, the temperatures recorded at 6.00 PM were in the range of 240C while the outdoor temperature was 160C. This was due to an increase in the number of occupants to 10 and the use of appliances generating heat and warming up the air.

The graph in Fig 4.3.1.4 clearly shows that the temperature variation throughout the space in various spots lie in the comfort range for an occupant in the computer lab.

4.3 SPOT MEASUREMENTS 4. INDOOR STUDIES | COMPUTER LAB 01

4.3.2 Relative Humidity

Apart from the temperature, spot measurements for relative humidity were also noted down at the same period (October 26th, 2021, at 9:00 am, 2:00 pm, and 6:00 pm). The results are depicted in Fig. 4.3.2.1, Fig. 4.3.2.2, and Fig 4.3.2.3. show recorded relative humidity levels ranging from a minimum of 42% to a maximum of 56% throughout the day at various spots in the computer lab, while the outdoor humidity level was around 62%

The higher values of the recorded humidity ranging from 53%-57% are during mid-day. However, the humidity level decreases to about 44% by evening. This can be attributed that the increase in temperature due to systems and occupants’ resulting in a drop in humidity levels.

The graph in Fig. 4.3.2.4 clearly shows that the relative humidity variation throughout the space in various spots is lower than that of the outdoor atmosphere.

4. INDOOR STUDIES | COMPUTER LAB 01

4.3 SPOT MEASUREMENTS

4.3.3 Illuminance

Similar to the previous analyses, the spot measurement for illuminance levels was conducted and are illustrated in Fig. 4.3.3.1 and Fig. 4.3.3.2 with and without artificial lighting in the space at 9 am.

At first, the illuminance level of the adjacent outdoor spaces, the New Yard and the Morwell street with a lux of 6225 and 8042 were registered respectively, which was the highest measured value of all. The illuminance level was then measured at the same time with and without artificial lighting in the room. The readings near the windows facing Morwell street was ranging from 20-60 lux, while the values of that near the window facing the new yard ranged between 40-68 lux when the lights were switched off. However, with the use of artificial lights, the illuminance levels ranged from 150 -250 lux and 270 -470 lux on the sides with windows facing Morwell Street and the new Yard respectively. The side of the new yard compared to the other spaces of the computed lab showed higher illuminance values, due to its sizeable south-west facing windows.

According to the measurements, the illuminance levels varied from 150-400 lux and 2-10 lux, with and without the usage of artificial lights respectively, in the central aisle. As already predicted in the previous analysis, the aisle presents a general lack of daylight and receives a negligible amount of daylight into the space. Lastly, it can be observed that there is a need for artificial lights to reach the range of comfort illuminance levels without which there are negligible daylight conditions in the space. However, various solutions may also be proposed to receive adequate daylight. It can be concluded that in general, the recorded measurements corroborate the findings which were predicted in the solar and shadow analyses.

The graph in Fig. 4.3.3.4 clearly shows that there is a significant variation in the illuminance levels with and without artificial lights.

4. INDOOR STUDIES | COMPUTER LAB 01

4.4 DAYLIGHT ANALYSIS

4.4.1 Theoretical Daylight Calculation

Daylight Factor

South-West Facade (Morwell Street)

Average Indoor Temperature 14.3

Average Outdoor Temperature 1826.8

Threshold Level

Recommended illuminance level 300

Daylight Factor 0.0078

Daylight Factor

North-East Facade (New Yard)

Average Indoor Temperature 14.3

Average Outdoor Temperature 1439.75

Threshold Level

Recommended illuminance level 300

Daylight Factor 0.0099

Before moving on to computational analysis, the team decided to conduct a theoretical study with regard to daylight availability. To carry out this experiment, the team conducted an on-site experiment of measuring the illuminance at three different spots, them being, the computer lab, the new yard, and the 16 Morwell Street at the same time (figure 4.4.1.3). This series of 8 recordings were done at an interval of 2 minutes for a span of 15 minutes. Figure 4.4.1.1 and figure 4.4.1.2 indicate the variation in lux levels and daylight factors respectively.

After averaging these values, a threshold level was calculated which showed that the computer lab receives about 9% to 20% of sufficient daylight for the northeast and southwest façade respectively, of the entire working year as seen in figure 4.4.1.4.

4. INDOOR STUDIES | COMPUTER LAB 01

4.4 DAYLIGHT ANALYSIS

4.4.2 Illuminance

To study the illuminance required for our computer lab, a series of computational analyses were carried out using parametric tools. Summer and winter solstice along with equinox were the three different times of the year, that were considered as our period of analysis.

Figure 4.4.2.1 clearly shows the inadequacy in daylight distribution for most parts of the year, the lowest being in December, with a certain increase in lux levels during summer. Due to less amount of natural daylight, it was concluded that certain usage of artificial lighting needed to be used, keeping in mind the function of the space.

4. INDOOR STUDIES | COMPUTER LAB 01

4.4 DAYLIGHT ANALYSIS

4.4.3 Daylight Autonomy | Useful Daylight Illuminance

Digital simulations were further done to compare the results with theoretical calculations and to understand the daylight availability of the space.

Figure 4.4.3.1 shows results from these simulations, which indicate a negligible percentage of daylight that is received throughout the year.

Similarly, figure 4.4.3.2 shows results for daylight autonomy, which further indicates that only 15% of daylight, throughout the year, receives a minimum of 300 lux.

These diagrams, helped us come to certain conclusions, one of which was that the need for artificial lighting was inevitable, taking into account the lack of natural light due to the obstructions, surrounding the space and certain specific requirements for work mode systems in terms of light.

Introduction Overview Outdoor Indoor Conclusions References Appendices

4.4 DAYLIGHT ANALYSIS 4. INDOOR STUDIES | COMPUTER LAB 01

4.4.4 Visualization

The same simulation tools helped us get image-based analysis for the computer lab. Figure 4.4.4.1 shows fisheye images with contour lines and fluorescent images, in candela per square meter. These images also indicate the inadequacy of daylight distribution throughout the interior of the space.

Through these studies the team was able to get a better understanding of the parameters that needed to be looked into. Solar control being one of them, however taking into consideration the space and its funtion, it is also important to note that the use of artificial light was inevitable, in order avoid glare and create discomfort for the occupants.

4. INDOOR STUDIES | COMPUTER LAB 01

4.5 DATA-LOGGER RESULTS

The data loggers were placed in the computer lab for indoor temperature data measurement and in the new yard, AA terrace, Bedford Square, and Morwell Street for the collection of outdoor data measurement (Fig 4.5.1- 4.5.4).

Due to the space being controlled by a central HVAC system, the conditions at which the measurements were taken were constant unless manually altered. During the logging period, the temperature was set to 22°C on the first 3 days (1/12- 3/12) and was altered to 18°C on 3/12. For the weekend (4/12- 5/12) the temperature was then set back at 23°C by the staff and then remained constant.

Based on gathered and evaluated data from the data-loggers, which are depicted in Figure 4.5.5 and the interview we had with the occupant, the following conclusions were drawn:

- The occupancy pattern in the working hours of the school varied between 5-15 occupants over the day during weekdays and a maximum of 6 occupants on the weekends. The windows on the northeast and the southwest sides of the space remain closed throughout the year. Due to the presence of a mechanical ventilation system, there is little influence from the occupants and external environmental conditions.

-The outdoor conditions differed each day, with a lot of alternations between cloudy, partly cloudy, and rainy weather. The outdoor temperature difference on the same day was 15 K (3/12). The maximum measured outdoor temperature was 11°C (03/12 at 19:00) and the minimum was 2°C (2/12 at 9:00).

-In general, it can be observed that there is a negligible variation in the temperature between outdoor spaces within the AA building premises and the ones outside.

Additionally, spot measurements were taken on 06/12 at 9:00, 12:00, and 16:00 and it was observed that there was a similarity in the datalogger measurements and the spot measurements.

Introduction Overview Outdoor Indoor Conclusions References Appendices

4.6 MInT STUDIES 4. INDOOR STUDIES | COMPUTER LAB 01

Moving on to the soft computations, three cases of the current scenario along with summer, winter weeks, and a solution case for summer were considered to predict the indoor temperatures.

For the first three cases, from figure 4.6.1 certain parameters were taken into account with the help of standards (CIBSE) and on-site measurements and calculations. These simulations were carried out for a day in November with an outdoor temperature of 150C. As observed in the graph, there is a significant increase in the indoor temperature as the number of occupants increase which in turn increases the heat gains due to appliance loads.

Similarly in the summer condition case, an outdoor temperature of 230C with a maximum of 37 occupants was considered, which showed a predicted indoor temperature of 35.10C, resulting in a rise of 120C above the outdoors. This resulted in an environmental condition where the occupants would experience extreme discomfort and the space would not be suitable for work. Hence as a solution for this, additional ventilation of 15 ac/h was provided along with changing the glazing properties and it was observed that there was a significant drop in temperature to 27.50C which is well within the comfort band.

Under winter conditions it is observed that due to a drop in temperature outside (80C), the predicted mean indoor temperature is well within the comfort limit. This case is done by considering maximum occupants with maximum systems on working mode.

Figure 4.6.2 emphasizes that the major reason for the rise in the indoor temperature is due to the appliances as compared to the solar gains. This varies with varying occupants. The temperature rise can be controlled by finding design solutions that help in increasing heat loss and thus improving the thermal performance of the computer lab.

It can also be observed that the rise in temperatures above outdoor for cases with maximum occupants is similar irrespective of the outdoor temperatures, however, there is a significant drop as soon as additional ventilation is provided.

4.7

Changing Glazing Properties

Use of Double Low-e argon glass, which helps in reducing external heat gains during summer and internal heat loss during winters (Figure 4.7.5). This also helps in increasing daylight in the space. The thin, transparent hard pyrolytic Low-E coating allows 67% of the solar heat gain to be transmitted and 78% visible transmittance into the space, aiming at comparatively higher daylight to enter the computer lab.

Controlled Natural Cross Ventilation

The use of natural ventilation and ventilative cooling is the potential for low operational energy use associated with low CO2 emissions and operational costs (Figure 4.7.1) (Dejan

Mumovic

et al, 2013)

Louvered Windows

Positioning of adjustable sashes to direct the wind flow. Due to the issue of security for windows towards Morwell Street, louvered windows at the top and bottom are the most optimum solution, still having a high ventilation capacity along with fixed windows in between, not obstructing visual comfort (Figure 4.7.2). In addition to this, the use of night shutters was introduced during winters, which would help retain the heat generated through the systems and balance the heat losses to gains during operational hours (Figure 4.7.4)

We further proposed operable sliding windows, facing towards the courtyard by eliminating security as an issue and can be controlled as and when needed by the occupants (Figure 4.7.3). However, it is important to note that louvered windows do have a less satisfactory seal and increased ventilation loss in winter (Dejan Mumovic et al, 2013).

Solar control strategies are adaptive for effective light distribution and glare prevention. Adaptability becomes a key issue when real-time control is needed to modulate between maximal and minimal exposure to the outside. The addition of louvers in the fenestration, allowing the room to run on a free-running mode, also allows reflection of incident daylight as the material of the louvers are acrylic and can be manually operated to optimize maximum daylight.

4. INDOOR | COMPUTER LAB 01

4.8 MODEL CALIBRATION

To achieve indoor comfort with energy efficiency, understanding the thermal performance of the space is very important, hence the team came up with several thermal simulations to understand how these spaces behave throughout the year, with the comfort band ranging from 19°C to 25°C. These simulations will be discussed in detail in the following section.

A 3D model was created using Rhinoceros, energy+, and open studio softwares. The specifications were derived from the data received from the architectural association archives. Table 4.8.1 shows the summary of the parameters used for this case. Here it was observed that there was a set temperature (HVAC) ranging from 18°C to 24°C. These conditions were applied throughout the year. It is important to note that the results obtained from the simulations will have slight variations, due to the varying parameters considered.

A comparison was made of onsite measurements and simulations carried out, for an operational period ranging from 1st December to 7th December in this case. Figure 4.8.2 indicates the graph where simulations are plotted against measured data. The two graphs were found to have a similar pattern in the temperature range.

4. INDOOR | COMPUTER LAB 01

4.9 THERMAL STUDIES

4.9.1 Annual Performance

the base case scenario in this section shows annual indoor temperatures along with annual heating and cooling loads. The simulations, in this case, consider the internal floors as adiabatic surfaces, hence an assumption is made that there are no heat gains and loosed from adjacent surfaces. This can be seen as a limitation, as the results can be affected by heat exchange through adjacent surfaces. Table 4.9.1.3 shows the considered parameters used to run simulations.

The seasonal schedule pattern used in the simulations is 10th January to 25th March and 25th April to 18th of December as an operational period with the rest being considered as a vacation.

A set temperature (HVAC) ranging from 22°C to 24°C throughout the day was considered as the base case along with simulations for free running with varying occupancy patterns. It is noted that there is no fixed schedule for several occupants. Hence a minimum of 3 and a maximum of 37 occupants have been considered throughout the cases, with a floor area of 125m2

Appliance load of 100 W per system as 60% working efficiency is considered, along with varying occupancy patterns. Lighting loads were assumed to be 8.5 W/m2, considering the base case scenario.

Figure 4.9.1.4 shows the annual graph for the base case and a free-running case with maximum and minimum occupancy. It was observed that the heat generated by the systems was one of the major reasons for heat gains, hence for most of the period, the free-running case is ranging away from the comfort zone. As a result, mechanical ventilation (HVAC) was used to achieve the required temperature range.

Figure 4.9.1.1 shows the annual heating and cooling demand with a significant energy consumption of 221 W/m2 and 35W/m2 respectively. These energy consumptions are relatively high. Annual heat gains and losses, from different parameters for the base case, can be seen in figure 4.9.1.2.

100 W per System

Introduction Overview Outdoor Indoor Conclusions References Appendices

4. INDOOR | COMPUTER LAB 01

4.9 THERMAL STUDIES

4.9.2 Typical Summer Week

The thermal performance for the base case, over a typical summer week, is seen in this section. As seen in figure 4.9.2.1, the period chosen for this week dates from 6 July to 12 July, where the outdoor temperature is ranging between 12°C to 21°C. The daily global horizontal solar radiation is seen to reach a maximum of 850 Watts. The indoor thermal comfort band is between 22°C to 27°C for the entire month. It is important to note that the operational hours are considered from Monday to Saturday, with Sunday being non-operational.

According to the simulation results it can be seen that, for free-running mode, with maximum occupancy, the temperature ranges from 27°C (minimum) to 43°C (maximum). However, the simulations with minimum occupancy show a temperature variation from 22°C (minimum) to 36°C (maximum). This indicates that the temperature ranges are not in the comfort zone during operational hours.

The HVAC base case result is hence achieved within the comfort band, with a cooling load of 2.03W/m2 for the considered summer week. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.2.2.

Typical Summer Week

4. INDOOR | COMPUTER LAB 01

4.9 THERMAL STUDIES

4.9.3 Typical Winter Week

The thermal performance for the base case, over a typical winter week, is seen in this section. As seen in figure 4.9.3.1, the period chosen for this week dates from 30 November to 6 December, where the outdoor temperature is ranging from 2°C to 13°C. The daily global horizontal solar radiation is seen to reach a maximum of 200 Watts. The indoor thermal comfort band is between 19°C to 25°C for the entire month. It is important to note that the operational hours are considered from Monday to Saturday, with Sunday being non-operational.

According to the simulation results it can be seen that, for free-running mode, with maximum occupancy, the temperature ranges from 7°C (minimum) to 22°C (maximum). However, the simulations for minimum occupancy show a temperature variation from 9°C (minimum) to 20°C (maximum). This indicates that the temperature ranges are below the comfort zone during operational hours.

The HVAC base case result is hence achieved within the comfort band, with a heating load of 6.86W/m2 for the considered winter week. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.3.2.

Introduction Overview Outdoor Indoor Conclusions References Appendices

4.9 THERMAL STUDIES 4. INDOOR | COMPUTER LAB 01 4.9.4 Summer | Mixed Mode

The thermal performance for the base case summer along with mixed-mode is seen in figure 4.9.4.1. It is important to note that usage of HVAC is considered for operational hours and natural ventilation is considered for non-operational hours, considering this scenario as the mixed-mode case.

According to the simulation results it can be seen that there is a significant overlap of the existing HVAC case with the mixed-mode case. The temperature for HVAC in the mixed-mode case is set to a range from 22°C to 24°C, which is giving a cooling load of 0.60W/m2. It can be seen from the graph that there is a slight shift in the peaks, which are still outside the comfort zone.

A comparison of the annual cooling demand, for the base case and mixed-mode case, can be seen in figure 4.9.4.3, which shows a drastic drop of 88.50% in energy consumption. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.4.2.

4. INDOOR | COMPUTER LAB 01

4.9 THERMAL STUDIES

4.9.5 Summer | Extra Ventilation + Additional Insulation

The thermal performance for the base case summer along with mixed-mode is seen in figure 4.9.5.1. It is important to note that usage of HVAC is considered for operational hours along with the use of natural ventilation as and when required by the temperature limit, considering this scenario as the mixed-mode case, along with introducing change in glazing properties for improving insulation.

According to the simulation results it can be seen that there is a significant overlap of the existing HVAC case with the mixed-mode case. Double Low-e argon glass, as additional insulation which helps in reducing external heat gains during summer, with a U-value of 2.08 W/K is used. The temperature for HVAC in the mixed-mode case is set to a range from 22°C to 24°C, which is giving a cooling load of 0.25W/m2. It can be seen from the graph that the slight shift from the previous case, is resolved in this one by achieving the temperature variations within the comfort zone.

A comparison of the annual cooling demand, for the base case and mixed-mode case, can be seen in figure 4.9.5.3, which shows a drastic drop of 88.50% energy consumption, which is further improved by the mixed-mode case to 89.50%. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.5.2.

4.9 THERMAL STUDIES 4. INDOOR | COMPUTER LAB 01 4.9.6 Winter | Mixed Mode

The thermal performance for the base case winter along with mixed-mode is seen in figure 4.9.6.1. It is important to note that usage of HVAC is considered for operational hours and natural ventilation is considered for non-operational hours, taking this scenario as the mixed-mode case.

According to the simulation results it can be seen that the temperature variations in the operational hours are within the comfort band, for the mixed-mode case. The temperature for HVAC in the mixed-mode case is set to 20°C, which is giving a heating load of 2.14W/m2.

A comparison of the annual heating demand, for the base case and mixedmode case, can be seen in figure 4.9.6.3, which shows a drop of 20% in energy consumption. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.6.2.

4. INDOOR | COMPUTER LAB 01

4.9 THERMAL STUDIES

4.9.7 Winter | Night Shutters + Additional Insulation

The thermal performance for the base case winter along with mixed-mode is seen in figure 4.9.7.1. It is important to note that usage of HVAC is considered for operational hours along with the use of natural ventilation as and when required by the temperature limit, and the use of night shutters during non-operational hours, considering this scenario as the mixed-mode case, along with introducing change in glazing properties for improving insulation.

Similar to the previous simulation results it can be seen that the temperature variations in the operational hours are within the comfort band, for the mixedmode case, however, there is an impact in the reduction of annual heating demand. Double Low-e argon glass, as additional insulation which helps in reducing external heat gains during summer, with a U-value of 2.08 W/K is used. Furthermore, introduction of 50mm thick night shutters with thermal conductivity as a common insulation material (0.04W/mK) is done. The temperature for HVAC in the mixed-mode case is set to 20°C, which is giving a heating load of 1.98W/ m2.

A comparison of the annual heating demand, for the base case and mixedmode case, can be seen in figure 4.9.7.3, which shows a drop of 20% in energy consumption, further improved by the mixed-mode case to 31.5% as mentioned above. Annual heat gains and losses, from different parameters for this case, can be seen in figure 4.9.7.2.

5. INDOOR STUDIES | COMPUTER LAB 02

5.1 SPATIAL LAYOUT

The analysis of computer lab 02 will be carried out in this section. It is located on the ground floor and accessed either through 39 Bedford square or 16 Morwell Street in the Architectural Association building premises. The computer lab is operational on all days throughout the year except for days when the school is closed for vacations.

In terms of the layout (Figure 5.1.1), the computer lab has an area of 20.70 m2 with a height of 3.5 m. This layout is considerably smaller than that of the computer lab studied earlier. It consists of computer work-stations parallelly placed across the room.

The room has top-hung windows on the northeast facade facing a small courtyard, and a casement window on the southeast facade facing a barren site. All windows are single-glazed (Figure 5.1.2, 5.1.3). The windows on the northeast facade consist of roller blinds and are openable up to 50%, while the other window with a higher sill level is fully openable and does not have any blinds. It can also be observed that due to no building obstructions in close vicinity with the space, a large amount of daylight is received through this fenestration. The room also consists of 3 radiators which are manually operated as per user convenience.

The flooring has black carpet and the workstations are of a white matt finish, which prevents glare. The walls and ceiling are white which gives a sense of a larger space as understood from occupant interviews.

The lab consists of 13 computers. Though the space has varying occupancy patterns, the computers are never turned off throughout the week. The maintenance and efficiency of the systems are affected by external environmental conditions.

Furthermore, the area is well equipped with ceiling-mounted compact fluorescent lights that are user-controlled as required.

Finally, the ceiling slab is exposed to the exterior along with a pyramidal skylight present at the center. Hence, given the name ‘Lantern room’ to this space. However, the skylight is currently closed by wooden paneling due to issues of security and excess glare into the room.

3 RADIATORS MANUALLY OPERATRED

PYRAMID SKYLIGHT CLOSED WITH WOODEN RAFTER 0 - 13 OCCUPANTS

ORIENTATION |NE - SW

DIMENSIONS | 5.3M x 5.4M

AREA | 20.70 SQ.M

COMPUTERS |13

WALL-WINDOW RATIO

NORTH EAST | 37%

SOUTH EAST | 15%

BLINDS | ROLLER BLINDS

NORTH- EAST WINDOWS

NORTH EAST SLIDING WINDOWS (2)

1.0 X 2.1M

SOUTH EAST CASEMENT WINDOW (1)

1.1 X 1.0M

5. INDOOR STUDIES | COMPUTER LAB 02

5.2 GENERAL SURVEY

To get a better judgment on the thermal performance of the spaces, the team conducted an online survey. These surveys were answered by students who were found to use the lab regularly. A total of 11 responses were received. When it comes to different opportunities for adaptive comfort, it is observed that a majority of students are well clothed, to improve their level of comfort. This was considered to be an important factor at the time of the survey, as the computer lab 02 is in free-running mode and has a radiator that can be mechanically controlled as and when required by the occupants.

In terms of thermal comfort, figure 5.2.1 shows a majority of 63% of occupants experiencing the space to be warm. Considering the volume of the computer lab 02, it was observed that the heat generated by the systems was one of the major reasons for heat gains. When it comes to noise levels, air quality, and visual comfort a majority of votes were towards a certain level of discomfort. Not having enough fresh air supply, good daylight distribution were some of the reasons for the above.

Some of the specific comments from the students, which said that the space felt too stuffy, lack of fresh air, was small for the number of systems showed clear signs of occupant discomfort, and helped the team analyze the parameters that needed to be worked on, to improve the indoor performance.

5. INDOOR STUDIES | COMPUTER LAB 02

5.3 SPOT MEASUREMENTS

5.3.1 Temperature

Temperature spot measurements were also noted down at the same period (October 26th, 2021, at 9:00 am, 2:00 pm, and 6:00 pm). The results are depicted in Fig 5.3.1.1, Fig 5.3.1.2, Fig 5.3.1.3.

The computer lab is a free-running module and is hence affected by the outdoor conditions to a greater extent when compared to the computer lab studied earlier. The windows being closed and the radiators not being in use were the conditions of the computer lab while the measurements were taken.

To begin with, the temperature in the computer lab with no occupants at 9.00 AM was registered at an average of 24°C, while the outdoor temperature which was registered on Morwell Street was 13°C. A difference of 11K was observed between the outdoor temperature and that of the computer lab. Similarly, the temperature recorded at 2.00 PM with occupants provided similar results with the indoor temperature being an average of 25°C though the outdoor temperature was 18°C. Furthermore, the temperature recorded at 6.00 PM with no occupants in the space showed a temperature range of 250C while the outdoor temperature was 160C. Due to the windows being closed and negligible changes observed in the space during the time of spot measurement, it is clear that was no significant effect by the external environment.

The graph in Fig 5.3.1.4 shows that the temperature variation throughout the space in various spots lie in the comfort range for an occupant.

To be able to identify potential causes of heat exchange and losses several thermal camera Images were taken. The images (Fig 5.3.1.5, 5.3.1.6, 5.3.1.7, 5.3.1.8 and 5.3.1.9) show a clear illustration of the heat transfers that occur within the openings of the room.

13°C

Figure

Temperature Analysis at 2:00 PM Sky Conditions | Clear

| 18.8°C Occupancy |

Temperature Analysis at 6:00 PM

5. INDOOR STUDIES | COMPUTER LAB 02

5.3 SPOT MEASUREMENTS

5.3.2 Relative Humidity | Illuminance

Humidity and Illuminance spot measurements were taken of the computer lab-2, on October 26th, 2021, at 3 different times of the day, namely at 9:00 am, 2:00 pm, and 6:00 pm under clear, cloudy, and partly cloudy sky conditions. The results depicted in Fig. 5.3.2.1, Fig. 5.3.2.2 and Fig. 5.3.2.3 shows relative humidity levels ranging from a minimum of 38% to a maximum of 50% throughout the day at various spots, while the outdoor humidity level was around 62%

The computer lab is a free-running module and is hence affected by the outdoor conditions to a greater extent when compared to the computer lab 01. Higher values of the recorded humidity ranging from 46%-50% are observed to be during mid-day around 2.00 pm, however, the humidity level is in the lower ranges of about 39-46% for early times of the day and the evenings. This can be attributed that the increase in temperature due to system and occupant-generated heat resulting in a drop in humidity levels.

The graph in Fig. 5.3.2.7 shows humidity variations throughout the space in various spots are lower than that of the outdoor atmosphere.

At first, a lux of 4025 was measured in the illuminance level of the adjacent outdoor spaces, the small courtyard, which was the highest measured value of all. The illuminance level was then measured at the same time with and without artificial lights in the room. The illuminance levels near the windows facing the courtyard were around 15-40 lux, while the values of that near the window facing the barren site ranged between 15-25 lux when the lights were switched off. However, with the use of artificial lights, the illuminance levels ranged from 150250lux and 270-470lux on the sides with windows facing courtyard and baren site respectively. The side of the barren site compared to the other spaces of the computed lab presented the higher illuminance values, due to the sill height, lesser building obstructions, and south-facing facade.

According to the measurements, the illuminance levels varied from 140-170 lux and 20-40 lux, with and without artificial lights respectively, in the central aisle. As already predicted in the previous analysis, the aisle presents a general lack of daylight and receives a negligible amount, as the skylight is covered by a solid wooden panel. The results depicted in Fig. 5.3.2.4, Fig. 5.3.2.5.

Lastly, it can be observed that there is a need for artificial lights to reach the range of comfort illuminance levels, however various solutions may also be proposed to receive adequate daylight. Hence, it can be concluded that the recorded measurements corroborate the findings which were predicted in the solar and shadow analyses.

The graph in Fig 5.3.2.8 shows that there is a stark variation in the illuminance levels with and without artificial lights.

5. INDOOR STUDIES | COMPUTER LAB 02

5.4 DAYLIGHT ANALYSIS

5.4.1 Illuminance

To study the illuminance required for our computer lab, a series of computational analyses were carried out using parametric tools. Summer and winter solstice along with equinox were the three different times of the year, that were considered as our period of analysis.

Figure 5.4.1.1 clearly shows the inadequacy in daylight distribution for most parts of the year, the lowest being in December, with a certain increase in lux levels during summer. Due to less amount of natural daylight, it was concluded that certain usage of artificial lighting needed to be used, keeping in mind the function of the space

5. INDOOR STUDIES | COMPUTER LAB 02

5.4 DAYLIGHT ANALYSIS

5.4.2 Daylight Autonomy | Useful Daylight Illuminance

Digital simulations were further done to understand the daylight availability of the space. Figure 5.4.2.1 shows the existing exterior image of the smaller computer lab. After enquiring to the facilities about the skylight being covered up from the inside, we were informed that the reasons were excess glare along with security issues. The team then identified the parameters required to resolve these issues, along with the lack of natural ventilation.

Figure 5.4.2.3 represents the daylight received by the room in the current situation with the skylight being sealed by a wooden panel, receiving a minimum of 7% of sufficient daylight. To resolve this, the wooden panel was then replaced by clear glass. However, though the room receives adequate light of almost 59% as observed in Figure 5.4.2.4, there is additional glare which is unfavorable for the working conditions. Furthermore, the skylight was covered with double Low-E argon glazing as a thermal barrier, allowing adequate daylight for 30% of the year as observed in Figure 5.4.2.5. The comparison for the same can be seen in Figure 5.4.2.2.

These iterations through simulations, helped us come to certain conclusions. The change in glazing properties, taking into account glare and security issues, can resolve and help achieve the recommended daylighting levels in the room.

5. INDOOR STUDIES | COMPUTER LAB 02

5.4 DAYLIGHT ANALYSIS

5.4.3 Visualization

The same simulation tools helped us get image-based analysis for the computer lab. Figure 5.4.3.1 shows fisheye images with contour lines and fluorescent images, in candela per square meter. These images also indicate the inadequacy of daylight distribution throughout the interior of the space.

Through these studies the team was able to get a better understanding of the parameters that needed to be looked into. Solar control being one of them, however taking into consideration the space and its funtion, it is also important to note that the use of artificial light was inevitable, in order avoid glare and create discomfort for the occupants.

5. INDOOR STUDIES | COMPUTER LAB 02

5.5 DATA-LOGGER RESULTS

The data loggers were placed in the computer lab for indoor temperature data measurement and in the new yard, AA terrace, Bedford Square, and Morwell Street for the collection of outdoor data measurement (5.5.1- 5.5.4)

Due to the space being in free-running mode, the conditions at which the data logger measurements were taken, are as follows:

- The windows were closed at all times on the first 3 days and were open to 25% during the operational hours, for the rest of the days of the logging period. The radiator was turned off for all days of the logging period, except for the last day.

-The occupancy pattern in the working hours of the school varied between 0-9 occupants over the day during weekdays and a maximum of 4 occupants on the weekends.

Based on the gathered and evaluated data from the data-loggers, depicted in Figure 5.5.5 and the occupant interview, the following conclusions were drawn:

-The outdoor conditions differed each day, with alternations between cloudy, partly cloudy, and rainy weather. The outdoor temperature difference on the same day reached 15 K (3/12). The maximum measured indoor temperature was 24°C (03/12 at 19:00) and the minimum was 19°C (4/12 at noon), while the maximum measured outdoor temperature was 11°C (03/12 at 19:00) and the minimum was 2°C (2/12 at 9:00).

- In general, it can be observed that there is a negligible variation in the temperature between outdoor spaces within the AA building premises and the ones outside.

-The temperature within the computer lab varied by 10K from that of the outside, it followed a similar pattern with the rise and fall in temperature on the first 3 days of the logging period (1/12- 3/12). However, there was a difference in the indoor temperature from 4/12 - 6/12 with a drop of 4-5°C from that was the previous, due to the windows being opened on the north-east facade during operational hours.

- As expected, from 4/12 - 6/12, since the windows were open during nonoperational hours, a temperature drop of 2-3°C was observed, ranging from 1922°C and reduced even further at times with zero occupants. Yet, the temperature always ranged within the comfort band almost for the entire measured period, ranging from 19-25°C.

- Furthermore, we observed a rise in temperature on the last day of the logging period as an effect of the radiator being turned on and the windows being closed in addition to the rise in outdoor temperature.

Additionally, spot measurements were taken on 06/12 at 9:00, 12:00, and 16:00 and it was observed that there was a similarity of the measurements taken in the dataloggers and the spot measurements.

Introduction Overview Outdoor Indoor Conclusions References Appendices

5. INDOOR STUDIES | COMPUTER LAB 02

5.6 MInT STUDIES

Moving on to the soft computations, three cases of the current scenario along with summer, winter weeks, and a solution case for summer were considered to predict the indoor temperatures.

For the first three cases, from figure 5.6.1 certain parameters were taken into account with the help of standards (CIBSE) and on-site measurements and calculations. These simulations were carried out for a day in November with an outdoor temperature of 150C. As observed in the graph, there is a significant increase in the indoor temperature as the number of occupants increase which in turn increases the heat gains due to appliance loads.

Similarly in the summer condition case, an outdoor temperature of 230C with a maximum of 13 occupants was considered, which showed a predicted indoor temperature of 33.90C, resulting in a rise of 10.90C above the outdoors. This resulted in an environmental condition where the occupants would experience extreme discomfort and the space would not be suitable for work. Hence as a solution for this, additional ventilation of 15 ac/h was provided along with changing the glazing properties and it was observed that there was a significant drop in temperature to 27.50C which is well within the comfort band.

Under winter conditions it is observed that due to a drop in temperature outside (80C), the predicted mean indoor temperature is well within the comfort limit. This case is done by considering maximum occupants with maximum systems on working mode.

Figure 5.6.2 emphasizes that the major reason for the rise in the indoor temperature is due to the appliances as compared to the solar gains. This varies with varying occupants. The temperature rise can be controlled by finding design solutions that help in increasing heat loss and thus improving the thermal performance of the computer lab.

It can also be observed that the rise in temperatures above outdoor for cases with maximum occupants is similar irrespective of the outdoor temperatures, however, there is a significant drop as soon as additional ventilation is provided.