The first and second law characteristics of fluid flow and heat transfer over a static and a moving wedge are investigated. With the help of suitable similarity transformations, the governing boundary layer equations for the velocity and temperature fields are transformed into ordinary differential equations and are solved numerically. The velocity and the temperature profiles are obtained for various parameters and are utilized to compute the entropy generation number Ns and the Bejan number Be. The effects of various physical parameters on the entropy generation number and the Bejan number are depicted through graphs and are discussed qualitatively. It is observed that the entropy production rate is less in case of wedge moving in the opposite direction to flow as compared to static wedge. 1. Introduction Newton’s second law of motion and laws of thermodynamics are the fundamental principles on which all the flow and heat transfer systems are built today. All other laws play a supportive role. First law of thermodynamics gives information about the energy of the system quantitatively. On the other hand, second law of thermodynamics states that all real life processes are irreversible. The irreversibility of the processes is measured by entropy generation. The pioneer work on entropy generation in flow systems was done by Bejan [1, 2]. He showed that the engineering design of a thermal system can be improved by minimizing the entropy generation. Later on, a lot of research has been done by many other investigators by taking different geometrical configurations related to the thermally designed systems and fluid flow processes. Sahin [3] analyzed the entropy effects in viscous fluid flow in a circular duct with the isothermal boundary condition. The first and second law characteristics of fluid flow and heat transfer in a channel having two parallel plates with a finite gap between them were analytically investigated by Mahmud and Fraser [4]. Yilbas et al. [5] discussed the entropy production effects in a semiblocked pipe by taking into consideration the swirling effects. The influence of magnetic field on entropy generation in laminar forced flow past a horizontal flat plate was examined by Al-Odat et al. [6]. Selamet and Arpaci [7] investigated the entropy effects in boundary layer flows. Makinde and Osalusi [8] studied entropy effects in a liquid film falling along an inclined heated porous flat plate. Makinde [9] extended his work and analyzed the irreversibility effects in non-Newtonian liquid film falling under the influence of gravity force. The
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