“…The dimensionless group forming the coefficient to the time derivative term in the Darcy equation is 1 χ , where χ = φPr Da was named the Vadasz number by Straughan (2001Straughan ( , 2004, followed by Lombardo and Mulone (2002), Mulone and Straughan (2006), Sheu (2006), Bhadauria (2007), Mahmud and Hashim (2011), Roslan, Mahmud and Hashim (2011), Bhadauria and Kiran (2013 and more. It is only through this combined dimensionless group that Prandtl number is affecting the flow in porous media.…”