BuffermetryFundamentals of moisture buffering Properties of hygroscopic materials Diffusion enhanced materials and structures Experimental: Sorption experiments Experimental: Diffusion experiments Incorporating the buffer in the construction Whole room simulations and experiments Experiment in the Passys environmental room Appendices - instruments and procedures Wiki howto |
Development of humidity buffering building materials - progress to November 2009The planned experimental work is nearly finished - measurements continue with double thickness perforated unfired brick, which has a very high buffer performance. We are scaling up to room size by taking over a larger version of our experimental chamber. This is a small room with a more robust flux generator. A standard condensation dehumidifier drips water into a weighed tank which has a heating coil as evaporator. A draft article is here (substantially changed November 23, 2009): Draft report (pdf 2Mb). The spreadsheet underpinning the numbers is here, and here is an explanation of the calculations. Anyone is welcome to comment here on this article. This page is editable. Particular queries: Can anyone improve on the unit name 'buf' with symbol B? Can anyone improve on the formulation of the buffer capacity as a single number? The meaurements will continue with other materials, currently leca block, but the research emphasis will shift to a study of the chemical properties of the unfired brick - particularly emission of sulphur dioxide through oxidation of iron sulfides in the original clay. We will also investigate the absorption by the bricks of pollutants such as acetic acid vapour, which is a problem in film archives. We note the successful completion of the DTU-BYG student project to investigate the physical properties of the unfired brick. A further project is now beginning: to investigate the possibility to use the brick as a solar powered dehumidifier for buildings. tim padfield 2009-09-06 |