CHEMICAL ENGINEERING TRANSACTIONS VOL. 40, 2014 A publication of The Italian Association of Chemical Engineering www.aidic.it/cet Guest Editor: Renato Del Rosso Copyright © 2014, AIDIC Servizi S.r.l., I SBN 978-88-95608-31-0; I SSN 2283-9216 Fluid Dynamic Simulation of Odour Measurement Chamber Giacomo Viccione*, Daniele Spiniello, Tiziano Zarra, Vincenzo Naddeo Department of Civil Enginggering, University of Salerno, via Giovanni Paolo II n. 132, 84084 Fisciano (SA), Italy (*e-mail: gviccion@unisa.it ; Tel. +39 089 963408; Fax +39 089 968806) Arrays of chemical sensors, generally used in electronic noses (e.noses), yield a unique pattern for a given mixture of odours. In recent years, there has been an increasing interest in applications of e.noses for the characterization and monitoring of environmental odours. While they have been around over the last three decades, little effort has been devoted to the development of the measurement chamber. Within it, all sensors are placed in contact of the flux of air to characterize in terms of odours. A measurement chamber must ensure standardized conditions in term of temperature, humidity and contact time of inflow air with the sensor surfaces. Aim of this work is to numerically analyse the fluid dynamic performance of measurement chambers with different geometry in order to improve sensor response signals in terms of stability, reproducibility and response time. The Fluid dynamic study was carried out by a Computational Fluid Dynamic (CFD) commercial software. Results show an objective methodological approach that can be used to design measurement chamber for electronic noses. 1. Introduction Odour emissions from industrial plants (e.g. manufacturing plants, wastewater treatment plants, etc.) into the atmosphere may cause significant public concerns and complaints (Ampuero et al., 2003, Zarra et al., 2008, Lehtinen et al., 2012). Effects of offensive smells should be assessed as well as proper actions must be taken for the control of odour annoyance according to related local legislations, when existing. One of the limits in the diffusion of legislation is the difficult in the standardization of the measurement of odour exposure in ambient air. Odours exposure can be continuously monitored by multisensory array systems commonly known as electronic noses (e.noses) (Gardner et al., 1994, Belgiorno et al., 2013, Capelli et al., 2014). E.noses are generally composed by a sampling system, a measurement chamber, a multi-sensor array, a data acquisition system and a pattern recognition algorithm (Pioggia et al., 2007). Up to date, many researches have studied the performance of different combination of sensors in odours detection and relative pattern recognition (Zarra et al., 2009, Giuliani et al., 2012), on other way little effort seems to have been made to study the optimization of the measurement chamber in terms of proper definition of chamber size and shape (Di Francesco et al., 2005), spatial displacement of sensors (Lezzi et al., 2001), allocation and geometry of a diffuser (Falcitelli et al., 2002, Pan et al., 2009). In order to guarantee proper sensors response, it is essential to ensure gas sample concentration at the sensors as uniform and steady as possible. In addition, time exposure, needed to record an “odour signature” and related to the modulation frequency, must be long enough to appropriately capture volatilized chemical compounds. The work here presented, based on a previous numerical study (Viccione et., 2012), aims to further clarify the fluid dynamic behaviour of a sensor chamber in order to guarantee homogeneous flow conditions, that is a volatile sample moving under nearly steady conditions and to minimize the presence of regions occupied by the pre-existing air as well as by stagnant and/or recirculating volatile vortexes. Volatile sample motion is solved in space and time by integrating Navier–Stokes equations, written for compressible fluids. The k-eps turbulence model is added for problem closure. Refer to our previous work (Viccione et al., 2012) about the way ruling equations are solved in time over the computational domain. DOI: 10.3303/CET1440019 Please cite this article as: Viccione G., Spiniello D., Zarra T., Naddeo V., 2014, Fluid dynamic simulation of odour measurement chamber, Chemical Engineering Transactions, 40, 109-114 DOI: 10.3303/CET1440019 109