lightSIMheat - Coupled building and lighting simulation for complex façade systems

Project leader University of Innsbruck: Wolfgang Streicher, Martin Hauer

Project staff: Matthias Werner, Daniel Plörer, Christian Kofler (Master student)

Project partner

Bartenbach GmbH

SFL Technologies

Funding organisation: FFG

Duration: 01.05.2013 - 31.12.2016

The use of complex daylight-guiding façade systems offers a high savings potential compared to the state of the art. Preliminary studies show a savings potential of almost 50% in total energy demand (heating, cooling, lighting). However, the simulation of such systems is currently still only possible to a limited extent.

Example of an innovative façade:

Office space with daylight control system

lichtlenkendes Tageslichtsystem — Light-directing daylight system

In lightSIMheat, a methodology and detailed numerical models are being developed for the coupled thermal and photometric building simulation of complex façade systems with integrated daylight control systems .

To this end, existing knowledge from the predecessor project "Light from Façade" is being utilised and the following topics are being implemented in greater depth:

Characterisation of the solar gain of complex daylight control systems with two-dimensional dependence on the angle of incidence (angle-dependent g-value)
Detailed basic development for the thermal and photometric modelling of complex daylight deflection systems
(Further) development of simplified calculation algorithms for thermal modelling of complex façade systems in TRNSYS, validation with the detailed model according to ISO15099 + BSDF (Bidirectional Scattering Distribution Function) (Fig. 2)
Development of a new TRNSYS type for time-step-coupled thermal and lighting simulation based on the 3-phase method in RADIANCE (Fig. 1)
Development of a prototype and testing of a new in-situ measurement concept for determining the g-value in façade systems with integrated louvre systems (Fig. 3)
Validation of the simulation models using detailed measurements in the g-value measurement chamber at Bartenbach GmbH and long-term thermal measurements at the Celllab of SFL technologies
Development of a simplified calculation algorithm as a basis for use in market-oriented planning and development tools