Experimental investigation of U value of double-glazed window with inter-pane blinds using Taguchi techniques

In this research article, Taguchi L18 orthogonal array has been employed on guarded heat plate apparatus to determine ‘unit heat loss rate’ (U value) of a double-glazed window with inter-pane venetian blinds by varying processes and glazing system’s parameters, i.e. temperature difference between hot and cold plates, low-emissivity (low-e) coating and its location, slat angle of blinds, pane spacing and hot plate temperature (selected as per composite climate in India). The analyses of the raw data and signal-to-noise (S/N) ratio of the response parameters have been performed using analysis of variance (ANOVA). The insignificance of temperature of hot plate has been reiterated. The optimum parameters predicted on the basis of analyses of S/N ratio (pooled ANOVA) are (a) temperature difference of 10 °C, (b) presence of low-e coating on inner surface of outside pane, (c) slat angle of 90° and (d) pane spacing of 32 mm. The quantification of the influence of various parameters on U value has been done through prediction of percentage contribution. The significant parameters in order of their decreasing percentage contribution are presence of low-e coating (49.2 %), slat angle (32.52 %), temperature difference between hot and cold plates (8.76 %) and pane spacing (4.33 %), respectively.