1 3 Experimental and numerical analysis of gas distribution in molten 4 carbonate fuel cells 5 6 7 Corrado Schenone ⇑ , Davide Borelli 8 Department of Mechanical Engineering – DIME, University of Genova, Genova, Italy 9 10 12 highlights 13 14  Flow rate distribution in a MCFC stack is analyzed to determine improvement actions. 15  The flow field inside a MCFC package of 150 cells is experimentally studied. 16  Flow rate distribution inside anodic and cathodic manifolds is numerically modellized. 17  Flow maldistribution for different operating conditions is assessed for both anodic and cathodic manifolds. 18  Different design solutions to get more uniform gas distribution inside the cell package are analyzed. 19 21 article info 22 Article history: 23 Received 2 September 2013 24 Received in revised form 24 January 2014 25 Accepted 5 February 2014 26 Available online xxxx 27 Keywords: 28 Fuel cells 29 Gas distribution 30 Maldistribution 31 Manifold 32 Numerical modelling 33 34 abstract 35 Flow maldistribution through the cell package affects the efficiency of the fuel cells, thus limiting the reli- 36 ability and the diffusion of such a technology. This subject is a key-point in the progress of the fuel cells, 37 so deserving the greatest attention and the most thorough research. This paper faces the issue by evi- 38 dencing the possibility to improve the quality of flow distribution through an appropriate design based 39 on the use of numerical methods. In particular, this research deals with the gas flow rate distribution in a 40 Molten Carbonate Fuel Cell (MCFC) and with the effect on maldistribution of baffles inserted into the inlet 41 manifolds. To this extent, an experimental set-up was built to analyze the flow field inside the cell: the 42 test section reproduces full-scale inlet manifolds for the anodic and cathodic supply of a MCFC stack of 43 150 cells. Experimental runs covered start-up as well as loading conditions. Air was used to simulate 44 actual flow conditions inside the fuel cell package, basing similarity on inlet Reynolds numbers equiva- 45 lence. Gas flow rate distribution has been evaluated by measuring the exit velocity at the outlet of the 46 experimental set-up, operating at different working conditions for both cathode and anode, with and 47 without the presence of baffles inside the inlet manifolds. Uneven distributions were observed for high 48 mass flow rates at the cathode manifold without baffle. For the anode, manifold flow distribution resulted 49 acceptably uniform for all working conditions. The baffle improved the distribution for both cathode and 50 anode manifold; particularly, sharp peaks of velocity observed for cathode in absence of the baffle disap- 51 peared at all. Then, velocity and flow rate distributions were modelled by means of a 3D computer code. 52 In order to validate the accuracy of the model, calculated results were compared with experimental data; 53 as a result, their agreement was very good and suggested the opportunity of a manifold design based on a 54 numerical approach. The numerical model was finally utilized to predict flow rate distributions for all 55 working conditions, by taking into account the detailed actual geometry of the manifolds. Numerical 56 analysis of flow rate distribution by means of specific indexes permitted to better understand critical 57 conditions and the reasons of maldistribution. The model was finally used to analyze various design 58 solutions and get a more uniform gas distribution of flow rates. Thus, the numerical modelling can be 59 effectively used during FC plants’ design to analyze the flow distribution, by taking into account devices 60 and systems to improve the uniformity of the distribution. In this way, the numerical modelling permits 61 to avoid expensive and time-consuming experiments, and to optimize, with a limited effort, the mani- 62 folds according to the cell package characteristics and mass flow rates. 63 Ó 2014 Published by Elsevier Ltd. 64 65 66 http://dx.doi.org/10.1016/j.apenergy.2014.02.006 0306-2619/Ó 2014 Published by Elsevier Ltd. ⇑ Corresponding author. Tel.: +39 010 3532577. E-mail addresses: corrado.schenone@unige.it, c.sche@libero.it (C. Schenone). Q2 Q1 Applied Energy xxx (2014) xxx–xxx Contents lists available at ScienceDirect Applied Energy journal homepage: www.elsevier.com/locate/apenergy APEN 4984 No. of Pages 22, Model 5G 17 February 2014 Please cite this article in press as: Schenone C, Borelli D. Experimental and numerical analysis of gas distribution in molten carbonate fuel cells. Appl Energy (2014), http://dx.doi.org/10.1016/j.apenergy.2014.02.006 C D er eri he he l dn la so fg sd ni nm