\begin{table}%t1
%\centering
\par
\small \caption{Values of the porosity, $p$, for particles with different $N$ and shapes (PCA and BPCA) used in the model.}\label{porosity}
\begin{tabular}{c c c}
\hline \hline
$N$ & $p$(PCA)& $p$(BPCA) \\
\hline
5 &  0.802  &0.689\\
15 & 0.951&0.817\\
30&  0.980&0.842\\
50 &0.990 &0.851\\
100 &0.996 & 0.859\\
\hline
\end{tabular}
\end{table}