Experimental and numerical study of the adsorption process in a carbon canister

Carbon canisters are used in automobiles to reduce evaporative emissions from the fuel system. Predicting the performance of a canister under different conditions can be useful in improving the canister design for efficient operation. In the present study, experiments were set up with fixed-bed carbon canisters to study the process of hydrocarbon adsorption. Time-accurate simulations have also been performed to model the adsorption process. Solutions from the experiment and simulations were compared. The computational fluid dynamics software FLUENT was used to simulate the cases.; The first set of experiments and simulations involved the use of isooctane for the adsorbate. Two canisters with different length-to-diameter ratios were used. Information such as the temperature history at four axial locations and the exit concentration were recorded. These plots were compared with those obtained from the simulations.; The next set of experiments and simulations used n-butane as the adsorbate. Three different inlet concentrations were studied. As before, the temperature history and exit concentration profiles were compared between experiments and the simulations. Results showed good agreement for all cases considered. The simulations were based on the Dubinin-Polanyi adsorption potential model and the linear driving force model.; A full factorial experiment set was designed to study the effect of the inlet flow rate and concentration on the breakthrough time, shape of the breakthrough curve and maximum bed temperature. A second-order regression model was used to fit the response to the two control parameters. Predictions from these regression models were found to have an average error of 3%.