the purpose of this study is to identify parameters influence on the particle deposition within fin and tube heat exchanger of air-conditioning systems by cfd analysis. first the basic sketch of periodic geometry drawn and meshing operation including boundary conditions was performed. then the gas side properties and flow parameters were solved by ansys fluent 14.5 software. lagrangian equation...

A comprehensive study of two-phase flow mechanisms and pressure drop in horizontal small hydraulic diameter tubes was conducted. Co-current flow of air-water mixtures in four round tubes and one rectangular tube with hydraulic diameters ranging from 5.5 mm to 1.3 mm were investigated. Bubble, dispersed, elongated bubble, slug, stratified, wavy, annular-wavy, and annular flow patterns were obser...

the performance of a γ-al 2 o 3 /n-decane nanofluid shell-and-tube heat exchanger in a biomass heating plant is analyzed to specify the optimum condition based on the maximum heat transfer rate and performance index for wide range of nanoparticle volume fraction (0–7%). compared with pure          n-decane, the obtained results in this research show that by using γ-al 2 o 3 /n-decane nanofluid ...

longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. in the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. the effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...

Studies show that the performance of transcritical R744 systems is highly sensitive to the high side pressure in the gas cooler. Hence use of appropriate strategy to control the high side pressure is essential to extract the best performance from these systems. In the present study, a R744 based air conditioning cycle with two expansion valves is considered for proper control of high side press...

Heat and moisture exchanging filters (HMEFs) can be blocked by secretions. We have studied HMEF performance under wet conditions to see which particular design features predispose to this complication. Dar Hygrobac-S (composite felt filter and cellulose exchanger), Dar Hygroster (composite pleated ceramic membrane and cellulose exchanger) and Pall BB22-15 (pleated ceramic membrane) HMEFs were t...

Heat exchangers: types .................................................................................................................................. 1 Plate heat exchangers ................................................................................................................................ 4 Shell-and-tube heat exchangers ............................................................