This study numerically investigates a double pipe heat exchanger with triangle and rectangle rib. The simulation is performed using ANSYS package, considering turbulent flow k-e turbulence model. working fluid water in both tube annulus the arrangement counter flow. results show that, transfer of rib are higher than that normal DPHE as Reynolds number increasing transfer, coefficient transfers ...

The low frequency noise from heat recovery steam generator (HRSG) makes dominant contribution to the noise on the boundary of plant, which generation mechanism is investigated in this presentation. The non-stationary flow field and aeroacoustic noise is studied with hybrid numerical simulation, which is comprised of CFD method based on Large Eddy Simulation (LES) and acoustic analogy by using F...

Shell and tube heat exchangers are widely being used in many of industrial and power engineering applications. Different techniques have been employed in order to enhance the performance of the heat exchanger. Air bubble injection is one method to increase the turbulence of the flowing fluids which in turn enhance the heat transfer performance. Injecting air bubbles is one of the promising tech...

In this paper, first the governing parameters characterizing low-finned tubes are reviewed. Second, the more important of the available performance correlations are compared with the available experimental data. The most reliable one can be employed to develop a pressure drop relationship, which has already been used in an algorithm for exchanger sizing. Also a means for the identification of a...

In most domestic and commercial refrigeration systems, frost forms on the air-side surface of the air-to-refrigerant heat exchanger. Frost-tolerant designs typically employ a large fin spacing in order to delay the need for a defrost cycle. Unfortunately, this approach does not allow for a very high air-side heat transfer coefficient, and the performance of these heat exchangers is often air-si...

This study aims to enhancement of heat transfer in double pipe exchanger by improving the thermal properties base fluid which is water adding AL2O3-Fe2O3 nanoparticles water. Al2O3-Fe2O3/water hybrid Nanofluid were examined experimentally and numerically at different flow rates ranging between (3 -7) Lpm temperature 25°C an external tube while there was a hot 60°C rate ranged – 5) running centr...

The article presents results of numerical and experimental analyses a tube-and-fin heat exchanger. numerous studies performed so far have proved that non-uniform inflow mediums in such exchangers may significantly affect their performance. aim the presented this is to investigate impact but controlled air on double-row exchanger was first modeled numerically determine its output at uniform medi...

In this paper, a dynamic heat exchanger model that unifies the frosting and defrosting analyses is presented. A novel scheme is proposed to solve the air flow redistribution due to non-uniform frost blockage. Unlike the existing defrost models which separate analysis for tubes and fins, the proposed defrost model unifies the analysis to maintain model consistency. The first-principles based fro...