RT Journal Article ID 2042a90c0dd17f77 A1 Campo, Antonio A1 Herranz, Luis E. T1 Expanded Lumped Model for the Algebraic Evaluation of the Total Heat Rejection from a Large Plate Immersed in a Fluid during a Period of Time JF Heat Transfer Research JO HTR YR 2009 FD 2009-03-30 VO 40 IS 4 SP 305 OP 319 AB Estimates of the total heat transfer from large plates by forced convection to neighboring fluids during a certain period of time has been traditionally obtained from the classic Gröber chart. This paper proposes a simple composite lumped model of the unidirectional heat conduction equation that articulates a handful of algebraic expressions. It is demonstrated that simple composite lumped model is a capable predictive tool in the entire range of the dimensionless Bi number. A compact correlation for the so-called mean "internal Nusselt number" varying with the dimensionless time has been developed. With this information, the total heat transfer can be evaluated effortlessly by algebraic means at all dimensionless times x. The accuracy provided by the expanded lumped model exceeded expectations. PB Begell House LK https://www.dl.begellhouse.com/journals/46784ef93dddff27,2f68fdd25315ad92,2042a90c0dd17f77.html