Comments on "Flow, thermal, and entropy generation characteristics inside a porous channel with viscous dissipation" by S. Mahmud and R.A. Fraser

Lead Engineer, Namavaran Delvar Engineering and Construction Company, Tehran, Iran We comment on the paper by Mahmud and Fraser [1]. The paper presents closed form solutions to the velocity and temperature distributions that would be very useful for benchmark checks of numerical computations. They are also useful for parametric studies for cases that involve large number of parameters. However, when such solutions are not free from mistakes one may no longer be able to use them. A typo in the average velocity, i.e. Eq. (10) of [1], is observed (in addition to some typos in the text for example Ref. [2] is repeated as [30]). The correct expression for the average velocity is  −∂∂=−DaDaDaxpu

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