A new transient analytical model for heat transfer of earth-to-air heat exchangers

Application of ZnO/TiO2 Nanocomposite for the Improvement of Heat Transfer Coefficient in Tube Heat Exchangers

The potential of nanofluids for the improvement of heat transfer coefficient in various heat exchangeequipment has been considered and studied as a major application during recent decades. In this research,heat transfer coefficient of ZnO, TiO2 and ZnO/TiO2 nanofluids in a shell and tube heat exchanger has beenstudied experimentally. ZnO nanoparticle was synthesized through pre...

A Fundamentally New Approach to Air-cooled Heat Exchangers

We describe breakthrough results obtained in a feasibility study of a fundamentally new architecture for air-cooled heat exchangers. In conventional “fan-plus-finned-heat-sink” air-cooled heat exchangers, the primary physical limitation to performance (i.e. achieving low thermal resistance) is the boundary layer of motionless air that adheres to and envelops all surfaces of the heat exchanger. ...

Heat Transfer to Separation Flow in Heat Exchangers

Analytical Entropy Analysis of Recuperative Heat Exchangers

The analytical solutions for the temperature variation of two streams in parallel flow, counter flow and cross-flow heat exchangers and related entropy generation due to heat exchange between the streams are presented. The analysis of limiting cases for the relative entropy generation is performed, and corresponding analytical expressions are given. The obtained results may be included in a mor...

Heat transfer enhancement due to air bubble injection into a horizontal double pipe heat exchanger

If an air flow is injected into a liquid fluid, many ambulant air bubbles are formed inside the fluid. Air bubbles move inside the liquid fluid because of the buoyancy force, and the mobility of these air bubbles makes sizable commixture and turbulence inside the fluid. This mechanism was employed to enhance the heat transfer rate of a horizontal double pipe heat exchanger in this paper. Howeve...