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In this study, results of HTRI Xchanger software used in the analysis of shell and tube heat exchangers (STHE), and Kern and Bell-Delaware methods, which are the conventional methods used for calculation of shell side heat transfer coefficient (SSHTC) and pressure loss (PL), were compared with experimental data. An experimental study was considered for Heat exchanger (HE) dimensions and fluid properties from literature. Then SSHTC and PL values were calculated using Kern and Bell-Delaware methods and HTRI Xchanger software for the measured shell side flowrates. SSHTC and PL values calculated for lower shell side mass flowrates by Kern method deviated from experimental results at low ratios. In addition, deviations in high flowrates values increasingly moved away from experimental results. In the Bell-Delaware method, although low deviations were observed in the high shell-side mass flowrates, the deviations increased at low flow rates and diverged from the experimental results. The deviation of SSHTC values calculated by the HTRI Xchanger program was found to be massively independent from the shell side flowrate. In addition, as in Bell-Delaware method, it has been observed that deviations in the shell side pressure loss (SSPL) calculations increased with increasing shell-side mass flowrate. As a result, SSHTC was calculated with average deviations of + 17, −11, and + 18%, by Kern and Bell-Delaware methods and HTRI Xchanger software respectively. Similarly, shell side PL was found with + 64, −25, and −32% average deviation, respectively. [ABSTRACT FROM AUTHOR]

In this study, the effects of geometric properties such as baffle spacing, baffle cut, sealing strips, gaps between heat exchanger components, number of tubes and tube passes have been investigated for shell and tube heat exchangers (STHE). For this purpose, geometrical dimensions and data of a specific heat exchanger (HE) used in an industrial application have been obtained. The HTRI Xchanger Suite Educational software was utilized to analyze the reference HE, to verify the results of the software and the output temperatures of the fluids, the shell side heat transfer coefficient (HTC) and the pressure loss (PL) values were compared with the experimental data. After confirming that the results of the software were within the acceptable deviation values, the geometric dimensions of the reference design were changed and new analyzes were carried out to examine the effects of several dimension options on the performance of STHE. Results were discussed in a detailed and comprehensive manner via curves. [ABSTRACT FROM AUTHOR]

• It is novel design of sudden expansion tube with dimpled fin. • Effect of D2/D1, DT, and NF vol.% on thermohydraulic performance investigated. • The bottom wall has performed higher convective heat transfer than the top wall. • The highest PEC occurred in D2/D1=2.5 and P/ d = 3 by using 2.0 vol.% NF at Re =2000. Sudden expansion geometry plays an important role in the design of many engineering applications such as heat exchangers to avoid thermal stress on welded joints. While the heat transfer in these geometries is maximized at the reattachment points, it decreases to a minimum in the recirculation regions created by the fluid. To prevent this situation and improve the performance of the expansion tubes, nanofluid, and expanded surfaces can be used. For this purpose, forced convection of magnetite nanofluid flow in various expansion ratios has been investigated numerically in this study. Analyses have been performed on Reynolds (Re) numbers ranging from 100 to 2000, constant and uniform heat flux at 600 W/m2, and volume concentrations (1.0≤ φ ≤2.0 vol.%). The result showed that while the Nu number increases with increasing Re number , the most efficient case is Dimpled Tube (DT) 9, and the highest value of performance evaluation criteria (PEC) has been obtained at φ =2.0 vol.%. Compared with the water, the highest Nu number value has been obtained as 3.34% increased at Re =2000 and φ =2.0 vol.%. When compared to the DT9 and Smooth Tube (ST) 1 where water was used as the working fluid at Re =2000 and φ =2.0 vol.%, the PEC value increased by 8.66% and 110.31%, respectively. In addition, the bottom wall of the DT9 case performs higher convective heat transfer rate than the top wall. [ABSTRACT FROM AUTHOR]