Review of advanced heat transfer enhancement techniques for next generation household heating systems

Global energy demands have been increasing at a rapid rate due to population growth, industrialization, and urbanization in recent years. Electric ovens utilized for cooking needs have low heating rates and low efficiency, having typical operating efficiencies of only 10–12%. The necessity to enhance heat transfer efficiency in such ovens to reduce energy consumption and environmental pollution. The present review takes a critical overview of various techniques utilized to enhance heat transfer with focus on utilizing fins, surface roughness, and air flow management. Heat transfer characteristics of micro fins, porous fins, and metal foam fins are discussed in detail. Surface roughness and emissivity effect on radiative heat transfer is discussed in detail. Fan blade and baffle design for improving air flow uniformity is discussed in detail with focus on uniform air flow and pressure drop minimization. With the considerable improvement so achieved, optimization of such techniques towards mass production is an illusion. Future research must be focused towards devices utilizing multiple techniques for maximum heat transfer efficiency. The review paper will act as a guide for researchers and engineers to design energy efficient heating devices. Keywords: Heat transfer enhancement, Energy efficiency, Household heatingappliances, Micro fins, Metal foam fins, Surface roughness, Airflow management,Thermal performance