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...

In this study, a reputable Kalina cycle system, KCS 11, is simulated and analysed. Within this efficient cycle, there are three heat exchangers: the first heat exchanger is designated for heat absorption from the heat source, the second heat exchanger is designed for heat release to the cold source, and the third heat exchanger is designed for energy recovery. In order to achieve precise si...

In the presented research, heat transfer of a mobile electrolyte alkaline fuel cell (AFC) (which the electrolyte has cooling role of system) has been considered. Proper control volumes of system with specific qualification have been chosen. Consequently, heat and mass transfer in control volumes have been assessed. Considerations on them and contributed models lead to approve a double tube heat...

This study presents an innovative and simple way to increase the rate of heat transfer in a spiral plate heat exchanger model. Several circular cross-section rods, as continuous vortex generators, have been inserted within the spiral plate heat exchanger in the cross-stream plane. The vortex generators are located at various azimuth angles of α=30◦, 60◦, 90◦, and 120◦ with non-dimensional diame...

many studies are performed by researchers about shell and tube heat exchanger but the multi-objective big bang-big crunch algorithm (mobba) technique has never been used in such studies. this paper presents application of thermal-economic multi-objective optimization of shell and tube heat exchanger using mobba. for optimal design of a shell and tube heat exchanger, it was first thermally model...

One of the key stages in designing a heat exchanger is optimization process. The enhancement in thermal performance results in a rise in pressure drop and total annual costs. So, finding optimal dimensions of heat exchanger is a key stage in designing process. In this paper, optimization has been done based on entropy generation minimization, where Cuckoo Algorithm aided to reach better results...

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...

Heat exchangers are widely used in power engineering and industrial applications, many techniques such as coiled tube, surface tension devices, rough surfaces, extended surfaces have been investigated to enhancethermal performance and to minimize the cost and size of the heat exchanger equipment. One of the most important techniques is tube insert. In general,tube inserts can be classified into...