Heat exchanger is an essential device used in complex engineering systems related to heat transfer processes in many industrial applications. Plate Heat Exchanger (PHE) is an important part of a condensing or evaporating system. Among many of factors which should concentrate on, the heat transfer and pressure drop is most important part during sizing and rating the performance of PHE. Due to th...

Leakage in heat exchanger tubes can result in unreliable products and dangerous situations, which could cause great economic losses. Along with fast development of modern acoustic detection technology, using acoustic signals to detect leakage in heat exchange tube has been gradually accepted and considered with great potential by both industrial and research societies. In order to further advan...

A numerical and experimental investigation of flow and heat transfer in a gas- liquid Thermosyphon Heat Exchanger "THE" with built in heat pipes and aluminum plate fins for moderate Reynolds numbers has been carried out. It's module is composed of 6 rows and 15 columns copper pipes with aluminum plate fins with dimensions of 130cm height, 47cm width and  20cm depth. The tubes have been fill...

Air pre-cooling equipment is normally being employed in air-conditioning systems for pre-cooling the ambient outdoor air to enhance the air-conditioning systems performance. In this study, the potential of a passive water-to-air heat pipe based heat exchanger (HPHEX) for air pre-cooling purpose in air-conditioning systems for the high cooling load demanding regions of Iran was investigated. To ...

Analysis of a thermoelectric generator (TEG) in an ocean thermal energy conversion (OTEC) application is presented. An analytic model is developed for describing the heat exchanger-TEG interactions. This model is used to illustrate limitations of applying conventional fixed junction temperature assumptions to systems experiencing significant temperature drops across the heat exchanger surfaces....

A-Type heat exchangers are used to meet required heat load with minimum duct dimensions in air-conditioning applications. This greatly reduces the air-conditioning system footprint in residential and commercial applications. The angle and tube spacing of the A-type heat exchangers should be optimized for minimum duct size and maximum heat load. However, existing air side heat transfer and press...

This paper provides a review on the fouling mechanism and its effect onto the performance of finned tube heat exchangers in HVAC systems. Fouling tends to degrade the performance of heat exchangers by decreasing the heat transfer coefficient and increasing the air-side pressure drop across the heat exchangers. Air side fouling depends on a number of factors on the air side, including type and c...

Leakage in heat exchanger tubes can result in unreliable products and dangerous situations, which could cause great economic losses. Along with fast development of modern acoustic detection technology, using acoustic signals to detect leakage in heat exchange tube has been gradually accepted and considered with great potential by both industrial and research societies. In order to further advan...

The paper presents two methods that are aimed at detecting fouling in cross-flow heat exchangers under normal operating conditions, using measurements that can easily be obtained, i.e. inlet and outlet temperatures and the mass flows of the hot and cold fluids. The methods are a) a physical method that is based on number of transfer units (NTU) relations and b) a black box model that is estimat...

1. The anatomy of the counter-current heat exchanger of skipjack tuna is described and the pattern of blood flow is analysed. 2. The pattern of blood flow is from the dorsal aorta, through the exchanger to segmental arteries to the tissues, from the tissues to segmental veins and back through the exchanger to the post-cardinal vein. 3. The vessels in the exchanger are about the same size as sys...