Hrishiraj Ranjan – författare

This Brief deals with heat transfer and friction in plate and fin extended heat transfer enhancement surfaces. It examines Offset-Strip Fin (OSF), Enhancement Principle, Analytically Based Models for j and f vs. Re, Transition from Laminar to Turbulent Region, Correlations for j and f vs. Re, Use of OSF with Liquids, Effect of Percent Fin Offset, Effect of Burred Edges, Louver fin, heat transfer and friction correlations, flow structure in the louver fin  array, analytical model for heat transfer and friction, convex louver fin, wavy fin, 3D corrugated fin, perforated fin, pin fins and wire mesh, types of vortex generators, metal foam fin, plain fin, packings, numerical simulation of various types of fins.

This Brief stands as a primer for heat transfer fundamentals in heat transfer enhancement devices, the definition of heat transfer area, passive and active enhancement techniques and their potential and benefits and commercial applications.

This Brief deals with externally finned tubes, their geometric parameters, Reynolds number, dimensionless variables, friction factor, plain plate fins on round tubes, the effect of fin spacing, correlations, pain individually finned tubes, circular fins with staggered tubes, low integral fin tubes, wavy fin, enhanced plate  fin geometries with round tubes, Offset Strip Fins, convex louver fins, louvered fin, perforated fin, mesh fin, vortex generator, enhanced circular fin geometries, spine or segmented fin, wire loop fin, flat extruded tubes with internal membranes, plate and fin automotive radiators, performance comparison, numerical simulation, advanced fin geometries, hydrophilic coatings, internally finned tubes and annuli, spirally fluted and  indented tube, advanced internal fin geometries, and finned annuli. The book is ideal for professionals and researchers dealing with thermal management in devices.

This Brief concerns heat transfer and pressure drop in heat transfer enhancement for boiling and condensation. The authors divide their topic into six areas: abrasive treatment and coatings, combined structured and porous surfaces, basic principles of boiling mechanism, vapor space condensation, convective vaporization, and forced condensation inside tubes. Within this framework, the book examines range of specific phenomena including  abrasive treatment, open grooves, 3D cavities, etched surfaces, electroplating, pierced 3D cover sheets, attached wire and screen promoters, non-wetting coatings, oxide and ceramic coatings, porous surfaces, structured surfaces (integral roughness), combined structured and porous surfaces, composite surfaces, single-tube pool boiling tests, theoretical fundamentals like liquid superheat, effect of cavity shape and contact angle on superheat, entrapment of vapor in cavities, nucleation at a surface cavity, effect of dissolved gases, bubble departure diameter, bubble dynamics, boiling hysteresis and orientation effects, basic principles of boiling mechanism, visualization and mechanism of boiling in subsurface tunnels, and Chien and Webb parametric boiling studies.

This Brief deals with Performance Evaluation Criteria (PEC) for heat exchangers, single phase flow, objective function and constraints, algebraic formulation, constant flow rate, fixed flow area, thermal resistance, heat exchanger effectiveness, relations for St and f, finned tube banks, variations of PEC, reduced exchanger flow rate, exergy based PEC, PEC for two-phase heat exchangers, work consuming, work producing and heat actuated systems. The authors explain Performance Criteria of Enhanced Heat Transfer Surfaces—the ratio of enhanced performance to the basic performance—and its importance for Heat Transfer Enhancement and efficient thermal management in devices.

This Brief deals with electrode design and placement, enhancement of both liquid and gas flow, vapor space condensation, in-tube condensation, falling film evaporation, correlations. It further provides a fundamental understanding of boiling and condensation, pool boiling, critical heat flux, convective vaporization, additives for single-phase liquids like solid particles, gas bubbles, suspensions in dilute polymer and surfactant solutions, solid additives and liquid additives for gases, additives for boiling, condensation and absorption, mass transfer resistance in gas phase (condensation with noncondensible gases, evaporation into air, dehumidifying finned tube heat exchangers, water film enhancement of finned tube exchanger), controlling resistance in liquid phase, and significant resistance in both phases. The volume is ideal for professionals and researchers dealing with thermal management in devices.