Abstract: A method for evaluating energy efficiency of electric arc furnace steelmaking comprises: obtaining original smelting information of the electric arc furnace; processing the original smelting information, and calculating an electrical energy efficiency evaluation index and a chemical energy efficiency evaluation index for process operation; wherein the electrical energy efficiency evaluation index comprises circuit efficiency, transformer tap capacity utilization rate and electrical energy thermal efficiency, and the chemical energy efficiency evaluation index comprises oxygen utilization rate, carbon powder utilization rate and chemical energy thermal efficiency; and evaluating an energy utilization condition of the electric arc furnace comprehensively based on the electrical energy efficiency evaluation index and the chemical energy efficiency evaluation index.

Abstract: A low geometric squish ratio piston for internal combustion engines to facilitate squish inducing mixing and intensified turbulence near engine top dead center The piston comprises a piston head having a height and a width and a depth with a top surface, and a skirt region with a ring region to define a body. The top surface defines an outer radius and is equipped with a combustion bowl recessed in the top surface and concentric therein to define an inner radius. The outer radius and the inner radius define a low geometric squish ratio. The combustion bowl has a deep piston center depth and a relatively high re-entrant angle at a periphery of the combustion bowl radius.