J. Alstan Jakubiec Jeff Neimasz Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 1 / 30

Transcription

1 Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module J. Alstan Jakubiec Jeff Neimasz Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 1 / 30

2 The Big Idea: Modeling Occupant Behavior and Control Systems Visual Comfort Occupant Behavior and Controls Daylight Availability Energy We want to model the effects of occupant behavior, experience and building controls on daylight availability and lighting energy use. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 2 / 30

3 The Ability to Model Different Kinds of Shading Systems No Shades Single Blind System Split Blind System Daylit Area 69% DA mean = 65% Lighting = 5.7 kwh/m 2 yr Daylit Area 45% DA mean = 45% Lighting = 7.8 kwh/m 2 yr Daylit Area 62% DA mean = 57% Lighting = 6.3 kwh/m 2 yr Percent of Occupied Hours % Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 3 / 30

4 Use Results in Thermal Simulations Oriented Towards Window (blinds primarily closed) EUI kwh/m Month Lighting [x20] Heating Cooling Lighting 11.8 kwh/m 2 Heating kwh/m 2 Cooling 34.9 kwh/m 2 Total kwh/m 2 (blinds closed 75% of occupied time) Oriented Away From Window (blinds open in Summer) EUI kwh/m Month Lighting [x20] Heating Cooling Lighting 8.4 kwh/m 2 Heating kwh/m 2 Cooling 48.7 kwh/m 2 Total kwh/m 2 (blinds closed 30% of occupied time) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 4 / 30

5 Behind the Scenes of DAYSIM and Climate-Based Metrics 100% Percent Occupied Hours 500lx (DA 500lx) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 5 / 30

6 Why Model Occupants? unobstructed. device might be open or closed as it makes a large difference in the amount of available daylight. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 6 / 30

7 In DIVA via the Shading Controls Button Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 7 / 30

8 Advanced Shading Results Overall Results Daylit Area Mean Daylight Factor Climate-Based Metrics Electric Lighting Use Occupancy Schedule Lighting Schedules Shading Schedules Effective Visual Comfort Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 8 / 30

9 Two Methods of Modeling Dynamic Shading in DIVA 1. Conceptual Dynamic Shading When shades are closed, direct component is neglected and diffuse component scaled by 25%. Only one simulation. Unnecessary to model shading geometry, but above assumptions are made. 2. Detailed Dynamic Shading Each state of a shading device (up, half-open, down, etc.) is simulated separately and pieced together annually based on shading controls. As many simulations as shading device states. Geometry of shading devices must be created in separate Radiance files. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 9 / 30

10 Detailed Dynamic Shading: Mechanical versus Switchable Detailed dynamic shading allows control over the geometry of shades, their operation, the setting of multiple shading states and material properties. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 10 / 30

11 Conceptual Dynamic Shading orange. 2 is found at a workplane node, conceptual blinds are closed until lunch or the next day. Setting workplane nodes is important, as it tells the simulation where people sit. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 11 / 30

12 Conceptual Dynamic Shading Results 100% Percent Occupied Hours 300lx (DA 300lx) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 12 / 30

13 How much does it matter? 100% Percent Occupied Hours 300lx (DA 300lx) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 13 / 30

14 Detailed Dynamic Shading - An Example We want to simulate fixed exterior louvers which can be rotated by the occupants or automatically controlled. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 14 / 30

15 Model Setup: Layers Each shading state gets placed on a separate layer. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 15 / 30

16 Model Setup: Shading Controls and the 30 and 60 degree layers make up state 1 and state 2 which are operated by the occupants. Nodes can be selected to inform the simulation where users sit or sensors are located. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 16 / 30

17 Simulation: Visual Comfort 30-degree (West View) 60-degree (West View) results for each shading state for the entire year. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 17 / 30

18 Simulation: Visual Comfort Annual glare simulations are run for both occupants sitting near the window, because either one might Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 18 / 30

19 Simulation: Climate-Based Metrics Select use DGP schedules to account for the visual comfort results you just simulated in controlling the shading when calculating annual illuminance metrics. Otherwise occupants will avoid direct 2 when controlling the louvers. Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 19 / 30

20 Results 100% Percent Occupied Hours 300lx (DA 300lx) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 20 / 30

21 Different Shading Control Scheme Options Controlled Manually by Visual Comfort 44.3% Mean Daylight Autonomy 6.2 kwh/m 2 /year Lighting Energy Controlled by Direct Sunlight on Workplane Sensors 41.9% Mean Daylight Autonomy 7.2 kwh/m 2 /year Lighting Energy Maintaining Less than 2500lx on the Workplane 39.1% Mean Daylight Autonomy 8.0 kwh/m 2 /year Lighting Energy Closing Shades During Unoccupied Periods in Winter (while maintaining less than 2500lx on the workplane) 39.1% Mean Daylight Autonomy 8.0 kwh/m 2 /year Lighting Energy Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 21 / 30

22 Automated Shading Controls: Thermal Control with Occupancy During unoccupied hours, close the shades during this cooling period Return to previous shading state if illuminance <500lx Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 22 / 30

23 Automated Shading Controls: Automated Glare Control Exterior illuminance that activates blinds to the room Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 23 / 30

24 Electrochromic Glass Example: SAGE Conference Room Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 24 / 30

25 Assumptions - Exterior Faribault Minnesota (44.33 N, E) N Weather File: USA_MN_Faribault.Muni.AWOS _TMY3.epw 1 mile away Conference Room Exterior modelled beyond 100 radius. 35% Reflectance for exterior surfaces (not measured) 10% Reflectance for ground surface (not measured) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 25 / 30

26 Assumptions - Interior Interior photograph 3/16/2012 1:15pm Occupancy: 8 am to 6 pm with DST Target work surface illuminance : 300 lux Lighting Set point 300 lux Interior sensors in lower right of right panes of Sage Glass Threshold set to 1.4 klx to 6.6 klx for vertical glass Manual control for Skylight glass. Rhino-Radiance Model Skylight: 62-2% VLT Ceiling: 80% Reflectance Floor: 20% Reflectance Wall: 60% Reflectance Southeast panes: SAGE Glass: variable % VLT Southwest panes: Clear Glass: 40% VLT Skylight panes: SAGE Glass: variable 62-2% VLT Fabric Shade: 5% VLT Floor: 20% Reflectance Wood trim: 35% Reflectance Work surfaces: 20% Reflectance Mullions: 20% Reflectance (metal) Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 26 / 30

27 Rhino Model - Sensor Locations Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 27 / 30

28 Sensor Illuminance with Electrochromic States Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 28 / 30

29 Results Fabric Shade - Manual Control DA300lux[50%] = 49% Shade is open 27% of occupied hours Electrochromic Shade - Sensor Control DA300lux[50%] = 100% Clear state (VLT 62%) 40% of occupied hours Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 29 / 30

30 Thank you. J. Alstan Jakubiec Solemma, LLC MIT Building Technology Jeff Neimasz Solemma, LLC Modeling Dynamic Shading Devices with the DIVA Advanced Shading Module 30 / 30