The aim of this thesis is to evaluate different ways of colouring the fluid layers of a fluidized glass façade system. Moreover, a cross-stream filtration process for reversible (de-)colouring is analyzed. The innovative components of the fluid glass system are the two fluid layers, which are thermally separated and which can be used for different purposes. Both liquid layers can be dyed to control the solar transmission through the façade element. Thereby the liquids work as shading devices and solar absorber. Overall, the fluid glass system replaces an insulating façade, a shading device, a heating and cooling system and functions as a solar collector within a thickness of a few centimeters. During the evaluation of different colouring options – mainly dyes and pigments – it was determined that dyes deviate strongly from the ideal transmission spectrum. Standard dyes do not absorb solar radiation in the near infrared area of the spectrum and therefore have a relatively high value for solar transmittance compared to the value for light transmittance. Consequently, dyes darken the room quickly, but lack in an efficient energy control. Furthermore, the use of dyes is restricted due to their lack of light fastness and their low values for the colour rendition index. Pigments, on the other hand, have better properties. Their spectral transmittance is very constant on a level that can easily be changed by in- or decreasing the concentration of the pigment. Therefore, the energy and light transmittance of Pigment A reaches the best values of the test. The colour rendition index remains on a very high level and the light fastness for pigments in general is higher than for dyes. The disadvantage of pigments is their tendency to agglomerate. Thus, particle size increases and the influence of scattering effects can reach a level, where the optical properties of the fluid layer deteriorate. The last part of the thesis is to determine an effective way of decolouring the fluid layers. Cross-stream filtration was chosen from a huge variety of different separation techniques. A reverse osmosis membrane for decolouring soluted dyes and an ultrafiltration membrane for decolouring dispersed pigments are evaluated in order to analyze the maximum rejection rate achievable and the energy demand. The work in this thesis shows that pigments outdo dyes concerning the main criteria. Moreover, it proves that cross-stream filtration is an effective way to decolour the fluid due to its high rejection rate. The calculated energy demand (0,057 kWh/m2a for Basacid) seems almost negligible compared to the total energy demand of ca. 52 kWh/m2a (Model-room, fluid glass façade, Munich, south-west-orientation), but it has to be stated, that this value might increase significantly because of the design of the membrane, which needs to be done in a subsequent work.     «

The aim of this thesis is to evaluate different ways of colouring the fluid layers of a fluidized glass façade system. Moreover, a cross-stream filtration process for reversible (de-)colouring is analyzed. The innovative components of the fluid glass system are the two fluid layers, which are thermally separated and which can be used for different purposes. Both liquid layers can be dyed to control the solar transmission through the façade element. Thereby the liquids work as shading devices...     »

The aim of this thesis is to evaluate different ways of colouring the fluid layers of a fluidized glass façade system. Moreover, a cross-stream filtration process for reversible (de-)colouring is analyzed. The innovative components of the fluid glass system are the two fluid layers, which are thermally separated and which can be used for different purposes. Both liquid layers can be dyed to control the solar transmission through the façade element. Thereby the liquids work as shading devices and solar absorber. Overall, the fluid glass system replaces an insulating façade, a shading device, a heating and cooling system and functions as a solar collector within a thickness of a few centimeters. During the evaluation of different colouring options – mainly dyes and pigments – it was determined that dyes deviate strongly from the ideal transmission spectrum. Standard dyes do not absorb solar radiation in the near infrared area of the spectrum and therefore have a relatively high value for solar transmittance compared to the value for light transmittance. Consequently, dyes darken the room quickly, but lack in an efficient energy control. Furthermore, the use of dyes is restricted due to their lack of light fastness and their low values for the colour rendition index. Pigments, on the other hand, have better properties. Their spectral transmittance is very constant on a level that can easily be changed by in- or decreasing the concentration of the pigment. Therefore, the energy and light transmittance of Pigment A reaches the best values of the test. The colour rendition index remains on a very high level and the light fastness for pigments in general is higher than for dyes. The disadvantage of pigments is their tendency to agglomerate. Thus, particle size increases and the influence of scattering effects can reach a level, where the optical properties of the fluid layer deteriorate. The last part of the thesis is to determine an effective way of decolouring the fluid layers. Cross-stream filtration was chosen from a huge variety of different separation techniques. A reverse osmosis membrane for decolouring soluted dyes and an ultrafiltration membrane for decolouring dispersed pigments are evaluated in order to analyze the maximum rejection rate achievable and the energy demand. The work in this thesis shows that pigments outdo dyes concerning the main criteria. Moreover, it proves that cross-stream filtration is an effective way to decolour the fluid due to its high rejection rate. The calculated energy demand (0,057 kWh/m2a for Basacid) seems almost negligible compared to the total energy demand of ca. 52 kWh/m2a (Model-room, fluid glass façade, Munich, south-west-orientation), but it has to be stated, that this value might increase significantly because of the design of the membrane, which needs to be done in a subsequent work.     «

The aim of this thesis is to evaluate different ways of colouring the fluid layers of a fluidized glass façade system. Moreover, a cross-stream filtration process for reversible (de-)colouring is analyzed. The innovative components of the fluid glass system are the two fluid layers, which are thermally separated and which can be used for different purposes. Both liquid layers can be dyed to control the solar transmission through the façade element. Thereby the liquids work as shading devices...     »