A gas contained within a pistoncylinder assembly undergoes three processes in series: Process 12: Constant volume from p1 5 1 bar, V1 5 4 m3 to state 2, where p2 5 2 bar. Process 23: Compression to V3 5 2 m3 , during which the pressurevolume relationship is pV 5 constant. Process 34: Constant pressure to state 4, where V4 5 1 m3 . Sketch the processes in series on pV coordinates and evaluate the work for each process, in kJ.
1. Introduction: Rough Surface in Contact I. Surface of Engineering Materials: Generals Surfaces have chemical properties, which are different from bulk virgin material. o Most metallic surfaces in air have oxide layers, which change the chemical and mechanical properties of the surfaces. Surfaces have mechanical properties, which are different from bulk material. o Machining or sliding contact makes strain hardened (or work hardened) layer and highly deformed layer, whose strength are different from bulk. Real engineering surfaces are rough. Mirror like smooth surface AFM image