Shell-side Pressure Drop Research Articles

Study on Shell-Side Heat Transfer Enhancement Using Cinquefoil Orifice Mixed-Flow Baffle

Abstract For traditional heat exchangers, segmental baffles form a “dead zone” on the leeward side of the baffle, reducing heat transfer efficiency and causing significant pressure loss in the shell side. In response to these issues, this paper proposed a new type of baffle—the cinquefoil orifice mixed-flow baffle which introduces cinquefoil orifices on the segmental baffle. This design retains some cross-flow while also inducing longitudinal jet-flow as the fluid passes through the cinquefoil orifice. Numerical results found that the cinquefoil orifice baffle not only reduces the adverse effects of the “dead zone” but also enhances turbulence in the shell-side fluid flow due to the jet-induced entrainment effect, thereby improving heat transfer efficiency. With identical boundary conditions, the cinquefoil orifice mixed-flow baffle heat exchanger demonstrated superior shell-side heat transfer effectiveness compared to the traditional segmental baffle configuration. For the heat exchanger studied here, when the cinquefoil orifice is positioned closer to the baffle cut, the shell-side Nusselt number can increase by up to 18.8%, concurrently leading to a reduction of 4.62% in shell-side pressure drop. But it is also found that with increasing the number of cinquefoil orifices, the shell-side heat transfer efficiency did not increase monotonically, implying that in addition of the locations of the cinquefoil orifices, the proportion of the longitudinal jet-flow to the cross-flow could be optimized to get a best heat transfer efficiency.

Comprehensive numerical investigation of the effect of various baffle design and baffle spacing on a shell and tube heat exchanger

This article explores the significance of Shell and Tube Heat Exchangers (STHX), with a focus on various baffle types such as Segmental, Double segmental, Helical, Disc-and-Doughnut, Clamping anti-vibration, and Flower-B. In this study, the commercial software ANSYS FLUENT is used to simulate the problem. The study evaluates their impact on heat exchanger performance using parameters like overall heat transfer coefficient (OHT), pressure drop (PD), and Performance Evaluation Criteria (PEC). Clamping anti-vibration, Flower-B, Helical, and Double segmental baffles exhibit reductions in shell side PD by 14%-28%. Despite OHT reductions in these designs, Disc-and-Doughnut baffles demonstrate a higher OHT (21%-24%) compared to Segmental baffles. Based on PEC values, Disc-and-Doughnut baffles are identified as the most favorable. Further investigation into different numbers of Disc-and-Doughnut baffles reveals increased OHT (17%-29%), PD (58%-59%), and cold water temperature (0.5%-1%). The STHX with Disc-and-Doughnut 10 baffles displays the highest PEC value, establishing it as the most effective STHX in the simulation.

Heat transfer performance study of Cu-ethanol/ethylene glycol/propylene glycol-water nanofluids in a wavy-walled tube heat exchanger

With the rapid consumption of nonrenewable energy sources, improving the heat transfer efficiency of conventional fixed tube plate heat exchangers, optimizing their structure, and finding more efficient coolants have become popular topics. In this paper, the cooling effect of ethanol/ethylene glycol/propylene glycol-water solution with a mass fraction of 50 % in a wavy-walled tube heat exchanger was investigated, while Cu nanoparticles with volume fractions of 1.5 % and 3.0 % were added to the cold working mass to form three different nanofluids. The effects of the three nanofluids at different volume fractions on the heat transfer performance of the wavy-walled tube heat exchanger were analyzed with numerical simulations, while the microscopic mechanism of the enhanced thermal conductivity of the nanofluids was investigated using molecular dynamics simulations. The results showed that the thermal conductivity of the nanofluids was greatly enhanced due to the formation of adsorption layers with different properties on the nanoparticle surfaces, and the Cu–ethylene glycol-water nanofluid showed the largest increase in thermal conductivity among the three nanofluids. It was also found that the shell-side pressure drop, convective heat transfer coefficient, and heat exchange quantity of the nanofluid in the wavy-walled tube heat exchanger significantly increased with an increase of volume fraction. The comprehensive heat transfer performance of the three nanofluids was found to be better compared to the base fluid. Cu-ethanol/EG/PG-water nanofluid with a volume fraction of 3.0 % increased the PEC of the heat exchanger by 10.4 %, 19.8 % and 27.6 %, respectively, at a volume flow rate of 1.53 m3/h. Therefore, the Cu-propylene glycol-water nanofluid had the best comprehensive heat transfer performance. Cu-ethanol-water nanofluid volume fraction of 3.0 % reaches a maximum PEC value of about 3.12 at Qv near about 2.0 m3/h, and Cu-EG-water nanofluid volume fraction of 3.0 % has a peak PEC value of about 4.07 at Qv of near about 2.0 m3/h. Therefore, the Cu-ethanol-water and Cu-ethylene glycol-water nanofluids are the optimal solutions for the combined heat transfer performance within the study.

An investigation on structural parameters optimization and coupled heat transfer of LNG submerged combustion vaporizer

Submerged combustion vaporizer (SCV) owns an extremely efficient multiphase heat exchanger adopted in the coastal liquefied natural gas (LNG) receiving terminal. Overall vaporization efficiency of SCV mostly depends on the matching relationship of structural parameters and coupled heat transfer characteristics, which has been rarely addressed in previous studies. In the present work, an integrated SCV experimental platform with handling capacity of 50 kg/h was set up to validate the reliability of numerical model and method. Additionally, on account of multi-parameter orthogonal combination optimization method, the effects and sensitivity orders of structural parameters (transverse tube pitch, longitudinal tube pitch, orifice size and number of distributor branch) on dynamics performance of SCV were investigated. Finally, the coupled heat transfer between gas–liquid two-phase flow and supercritical LNG gasification was revealed in view of optimized parameters. Results indicated that the transient numerical tube-side outlet temperature could be consistent with experimental data. For the shell-side heat transfer coefficient, the sensitivity order was transverse tube pitch > orifice size > longitudinal tube pitch > number of distributor branch. Nevertheless, for the shell-side pressure drop, the sensitivity order was longitudinal tube pitch > transverse tube pitch > orifice size > number of distributor branch. Under the condition of optimization scheme, the heat provided by gas–liquid two-phase flow could meet the requirements of supercritical LNG gasification, the NG outlet temperature might achieve approximately 272 K. The present outcomes could lay a foundation for the optimization design and deep understanding for actual SCV facility.

Thermo-hydraulic design of a horizontal shell and tube heat exchanger for ethanol condensation

Horizontal shell and tube condensers are widely used in several industrial applications due to its versatility and heat transfer efficacy. In the present work, the thermo-hydraulic design of a horizontal shell and tube heat exchanger intended to condense 25,000 kg/h of a pure ethanol stream was carried out. Several key design parameters were calculated such as the number of tubes, heat transfer area, overall heat transfer coefficient, shell internal diameter, baffle spacing, as well as the pressure drop for both streams. The heat exchanger type is of pull-through floating head, and will present a number of tubes of 731, a heat transfer area of 223.68 m2, an overall heat transfer coefficient of 499.36 W/m2.ºC, a shell internal diameter of 1.684 m and a baffle spacing of 0.674 m. Around 157 kg/s of chilled water will be required for this heat transfer service. The values of both the shell side (10,069.25 Pa) and tube side (42,192.63 Pa) pressure drop are below the maximum values set by the process.

Validation of modeling scheme implementing MULTID component of MARS-KS code to predict shell-side pressure drop in shell-and-tube type heat exchangers

A modeling scheme to predict the pressure drop on the shell side of the shell-and-tube type heat exchanger is developed, which is using the system thermal hydraulic code, MARS-KS. In the present scheme, the shell side of the heat exchanger is modeled by the MULTID component in rectangular shape in which, the part blocked by the segmental baffle plate and the opening part by the baffle cut are modeled by separate nodes. The form loss coefficients and its distribution for the junctions of the shell side are estimated by the assumption of the same pressure drop in each cross pass of the shell and then finalized by iterative calculation. To prove the validity of the modeling scheme, calculations are made to simulate the experiments conducted at the test heat exchanger having a size used in the industries. It is discussed whether each effect of the size of inlet/outlet nozzle and the height of the baffle cut on the overall pressure drop of the heat exchanger is properly predicted and consistent with the experimental observations. Also, the effectiveness of consideration of leakage at the clearance between the shell and the segmental baffle plates is discussed in resolving the problem of over-predicted pressure drops in the high flow region. For the simplification, the use of one-dimensional modeling to this problem is attempted. The applicability of the present method and results to the different heat exchangers is also discussed.

A design model for spiral wound heat exchangers which accounts for property variation, longitudinal heat conduction, and heat-in-leak

• A combined analytical-numerical design model for cryogenic SWHE is developed. • Analytical sizing module finds the optimum configuration of SWHE. • The effects of property variation, LHC, and heat-in-leak are investigated. • LHC impact is negligible compared to property variation and heat-in-leak. • A sensitivity analysis on the input constraint is performed. Spiral Wound Heat Exchangers (SWHEs) can be a good and reliable choice for serving as the main heat exchanger in the cryogenic gas liquefaction cycles using throttling process such as the Linde-Hampson cycle. In this application, a high pressure hot gas stream has to be cooled down via transferring heat to a low pressure cold gas in a high-effectiveness heat exchanger. Present research has been organized to develop a design model which is able to find the optimum SWHE configuration for gas liquefaction cycles. The model has to be capable of considering the important physical phenomena in the cryogenic temperature ranges, including variation of fluid properties with temperature, longitudinal heat conduction (LHC) through separating walls, and heat-in-leak. Therefore, a combined analytical-numerical design model has been developed in the present study. The design model is essentially composed of two stand-alone modules, i.e. an analytical sizing module and a numerical performance evaluation module. To develop the design model, first, the geometrical characteristics of SWHE are studied and primary geometrical parameters are recognized. Then, the analytical sizing module is developed which is able to determine the optimum values of primary geometrical parameters of SWHE minimizing the heat transfer surface area based on the input design requirements. Afterwards, a 1D finite difference numerical module is presented in which important physical phenomena can be considered in the evaluation of the thermo-hydraulic performance of all types of counter flow or parallel flow heat exchangers as well as SWHEs. Finally, the two modules are combined to construct a design model. Two examples in which the low pressure superheated vapor helium is intended to cool down the high pressure supercritical helium flowing inside the tubes are also provided to demonstrate the applicability of the proposed combined model, and also, to elucidate its sensitivity to the input constraints. It was concluded that while variations of fluid properties and the external heat fluxes due to the radiation and convection have significant influence on the performance of cryogenic SWHE, the LHC is of minor importance and can be neglected. Moreover, decreasing the shell-side allowable pressure drop from 10 kPa to 2 kPa, causes the heat exchanger length and its outside diameter to increase by 79% and 48%, respectively.

Numerical and experimental study of a shell and tube heat exchanger for different baffles

AbstractIn the present work, the shell and tube heat exchanger (STHX) is designed based on The Tubular Exchanger Manufacturers Association standards with hot fluid (water) flowing on the shell side and cold fluid on the tube side. A comparison is made between the Nusselt number and friction factor obtained from numerical and experimental results of segmental baffles (SBs) and helical baffles (HB) with different baffle inclinations. The results show that SB provided a higher Colburn factor (js) when compared with HBs STHXs (20°, 30°, 40°, and 50°), but shell side pressure drop is lower for 40° HBs STHXs for the same shell side fluid flow rates.

Numerical analysis of thermal performance of waste heat recovery shell and tube heat exchangers on counter-flow with different tube configurations

This study investigates the effect of tube layout configurations on the hydraulic-thermal performance of shell-and-tube heat exchangers (STHXs) as waste heat recovery systems. The STHXs are triangular (30°, STHX-T), rotated triangular (60°, STHX-RT), and combined (STHX-C). Water at a temperature of 10 °C was circulated through a bundle of tubes inlet to recover waste heat from hot water at the temperature of 65 °C. Water was circulated through the shell inlet within the mass flow rate range of 0.5 ≤ ṁ ≤ 3.5 kg/s. ANSYS-Fluent was used to perform a three-dimensional computational study under steady-state conditions. The turbulence model, realizable k-epsilon, was adopted because of the possible transition from laminar to turbulence. The results were validated with the Kern correlation for shell-side heat transfer coefficient and pressure drop. The temperatures, pressure drop, velocity, and overall heat transfer coefficient for all the cases were compared. Temperature contours, pressure contour, velocity vector, and velocity contour were presented for flow visualization. When the simulation results of the different STHXs were compared, the results revealed that the STHX-T layout has the highest overall heat transfer coefficient of 2307.09 W/m2K. The maximum pressure drop of 242.42 Pa, highest temperature drop in the shell zone of 4.48 K, and highest temperature rise in the tube side of 6.67 K, followed by STHX-C and STHX-RT layout were obtained.

Heat exchanger network optimisation considering different shell-side flow arrangements

Heat exchanger network synthesis (HENS) is an effective tool for heat recovery in chemical and petrochemical industries. This study aims to show a method for HENS with the consideration of different shell-side flow arrangements in shell-and-tube heat exchangers. The proposed MINLP model is modified from the stage-wise superstructure model, incorporating newly developed correlations for shell-side pressure drop calculation for the helical baffle. The objective is to minimise the total annual cost (TAC) with a trade-off between the cost of different shell-side heat exchangers, utility cost, and pumping cost. The selection of baffle design is decided by the saved pumping cost and the increased area cost. The proposed model is tested from different points of view: with/without utility constraints and different statuses of the streams. Three case studies are presented and compared with the results from the literature. The proposed method with different shell-side baffles can reduce the heat transfer area and pressure drop. For fixed utility consumptions, the TAC in a case study is decreased by 8.9% with mixed baffle types. Although the unit per area cost of the helical baffle is higher than the segmental baffle, the increased investment cost could be compensated by the reduced operation cost, especially for plants with high viscosity streams and long-term cost-saving.

A comparative numerical study of shell and multi-tube heat exchanger performance with different baffles configurations

This study presents a numerical modeling of a shell and tube heat exchanger to analyze six various baffle configurations for increasing the thermal parameters performance and hydraulic parameters performance. The baffle configurations include conventional single segmental (CSS), staggered single segmental (SSS), Flower segmental (FS), hybrid segmental (HS), circular ring baffle (CR), and circular ring with holes (CRH) baffles. Flow of water field characteristics, pressure loss, and heat transfer performance, including effectiveness (ε) and the heat transfer coefficient (h) are studied with a variation of Reloads numbers from 10500 to 38500 to analyze the best performance. The effectiveness and the heat transfer coefficient increase with increasing the Reynolds numbers. The HS configuration results are the largest shell side pressure loss while HS and CR thermal influence on heat exchanger performance augmentation is found to be more significant compared to other configurations for all test cases. Compared to the CSS and SSS baffle configurations, the dead spaces and the recirculation zones are disappearing in both FS and HS configurations where the RCH is superior in overcoming the dead zones completely. The maximum values of the effectiveness and heat transfer coefficient of STHX are achieved in the case of CRH type with enhancement about 166% and 142% respectively, compared to CSS baffle. The CRH accomplished less friction losses than hybrid and ring baffles where the shell side pressure drop for HS was the highest value. The heat transfer coefficients per pressure loss of the RCH are about 138% higher than that of other configurations.

A Numerical Approach to Study Shell-Side Fluid Flow in Shell-and-Tube Heat Exchangers

The detailed CFD simulation of the shell-side flow inside shell-and-tube heat exchangers results prohibitive for large-size components, due to the large number of tubes, together with the multi-scale nature of the flow features. To overcome this issue, the porous media approach can be adopted, substituting the tube bundle with a porous domain, where a suitable momentum sink term in the Navier-Stokes equation is provided. In this paper, a novel numerical approach to estimate the crossflow shell-side pressure drop is presented: a complete characterization of the tube bundle was performed by running 2D-CFD steady-state isothermal analyses, collecting pressure gradient magnitudes and directions for different mass flow rates and angles of attack of the incoming flow. The approach was validated against numerical results and compared to the methodologies currently available. Models, assumptions, and boundary conditions are herewith reported and thoroughly discussed, alongside the main results obtained.

Design, Fabrication and Performance of Twisted Tube Heat Exchanger

Abstract: Heat exchangers are very much essential industrial as well as domestic equipment usedeveryday. The fundamental basis for this statistic is shell and tube technology is a cost effective, proven solution for a wide variety of heat transfer requirements. There are various limitations with technology which include inefficient usage of shell side pressure drop, dead or low flow zones around the baffles where fouling and corrosion can occur, and flow induced tube vibration, which can ultimately result in equipment failure. This paper presents a recent innovation and development of a latest heat exchanger technology, known as Twisted Tube Technology, which has been able to overcome the limitations of conventional technology. This technology provides solution to almost all mentioned problems and provide good overall heat transfer coefficients through tube side enhancements. This paper primarily focuses on thermal analysis on twisted tube Heat exchangers. Keywords: Heat exchangers, Twisted tube technology, conventional technology, thermal analysis

Experimental investigation on heat transfer performances in half-cylindrical shell space of different heat exchangers

The superheated steam cooling section and the condensate cooling section of the power plant feedwater heaters and the countercurrent U-tube heat exchangers all involve heat transfer in half-cylindrical shell space. The overall and shell-side heat transfer coefficients (h.t.cs.), pressure drop, and the comprehensive performances of some half-cylindrical space heat exchangers with different baffle structures were experimentally investigated. The investigated structures include three ladder helical baffle types [single inclined ladder helical (SH), dual inclined ladder helical (DH) and folded ladder helical (FH)], three orifice baffle types [fillet triangle orifice (F), trefoil-orifice (T) and quatrefoil-orifice (Q)], and segmental baffles (S), and all schemes are of two baffle pitches. Under the same baffle pitch and working condition, the experimental results show that the shell-side h.t.cs. of the ladder helical baffle schemes are higher than those of the orifice baffle schemes and segmental baffle ones; and the shell-side pressure drops of the orifice baffle schemes are much lower than those of the ladder helical baffle schemes and the segmental ones. The values of average comprehensive index hoΔpo−1/3 of the ladder helical schemes FH-40, DH-40 and the orifice baffle schemes F-40 and T-40 are respectively 14.26%, 17.58%, 15.62% and 12.82% higher than that of the segmental scheme S-40.

Numerical study on the flow characteristic of shell-side film flow of floating LNG spiral wound heat exchanger

A mathematic-physical model was established to investigate the shell-side flow characteristic of film flow in spiral wound heat exchanger (SWHE), which was used for floating liquefied natural gas (FLNG). The numerical study was carried out based on CLSVOF model and dynamic contact angle model, and the numerical accuracy was validated by experimental data. According to the results under static conditions, the shell-side frictional pressure drop gradient increased with decreasing pressure and increasing mass flux and heat flux. Sloshing motion could significantly shorten the process of film flow in the heat exchanger, promote the early occurrence of flow pattern transition and lead to the remarkable change in frictional loss. Therefore, the effects of sloshing parameters and working parameters on shell-side frictional pressure drop gradient were investigated, where sloshing amplitude, sloshing period, pressure and mass flux respectively were 5 ∼15o, 5 ∼ 15 s, 0.2 ∼ 0.6 MPa and 60 ∼ 100 kg/(m2·s). As a result, in order to maintain the stable operation of FLNG SWHE, the heat exchanger should be placed near the gravity center of FLNG, and the shell-side pressure and mass flux should be respectively increased to 0.6 MPa and 80 kg/(m2·s), as far as possible. These results will provide some instructions in the design and operation for FLNG SWHE.

Modeling of heat transfer of supercritical water in helical finned double pipe

Supercritical water (SCW) is a promising fluid for achieving high thermal efficiency. In the present work, the SST k-ω turbulence model is employed to numerically simulate flow and heat transfer behavior of supercritical water in horizontal double pipe with helical fins. Grid independence test was firstly carried out and then model was validated with experimental data. Different combinations of width, height and pitch in helical double pipe numerical model, width varying from 2 mm to 4 mm, height ranging from 2 mm to 6 mm and pitch available from 15 mm to 25 mm, were examined. In addition, effects of buoyancy force, hot fluid temperature and mass flux on the heat transfer performance were investigated. Buoyancy disturbs the flow field by inducing secondary flow. The flow field is symmetrically distributed on the tube-side. In contrast, the presence of the fins in shell-side breaks the symmetrical distribution and generates a swirling flow at the top of the fins. The results indicated that the peak tube-side and overall heat transfer coefficients emerged at hot fluid slightly greater than the pseudo-critical point temperature. Moreover, the overall heat transfer coefficient improved as mass flux on both the tube-side and the shell-side. However, the shell-side would induce a greater magnitude. Also, the shell-side pressure drop closely related to the shape factor and increased with it. The performance evaluation criterion for case 8 and case 9 were 2.08 and 1.88, respectively. Nevertheless, the pressure drop of case 8 was more than twice case 9. Consequently, case 9 may be an optimal configuration simultaneously considering the coupling effect of heat transfer and pressure drop.

Building a MATLAB applicaton for preliminary design and optimization of shell and tube heat exchangers

Designing shell and tube heat exchangers is a complex and time-consuming procedure. Since they are one of the most common process units in process industry, great effort should be made to improve their design and to facilitate the design procedure. Therefore, in this study, an easy-to-use MATLAB application for shell and tube heat exchanger preliminary design and optimization was developed. The application enables users to select operating parameters manually and test their effect on heat transfer area and pressure drop. Moreover, the application helps users to optimize the preliminary design, in terms of finding the minimal heat transfer area required to meet the process requirements. The validity of the application was tested on the example from the literature, where the heat transfer area was 61.91 m2. During the proposed optimization procedure, different parameter values were tested and an optimal combination of parameters was found within 5 seconds (for all combinations), resulting in the heat transfer area of 53.27 m2. The application has a great feature of displaying the impact of baffle cut value and baffle spacing on most important design parameters: heat transfer area, tube-side pressure drops and shell-side pressure drops. Also, new correlations were developed for the calculation of the Colburn heat transfer factor and friction factor as a function of Reynolds number and baffle cut value. Overall, the application has proven to be useful for the preliminary design of shell and tube heat exchangers, and can represent the foundation for the development of advanced heat exchanger design applications.

Parametric & CFD Analysis of Shell and Tube Heat Exchanger by Varying Baffles Geometry

The Shell and Tube Heat Exchanger are most commonly used in current industrial production. In this study, the effect of baffle spacing on pressure drop and heat transfer coefficient are considered in a shell and tube heat exchanger with single segmental baffles and staggered tube layout. The effects of number of baffles are considered 4, 6, 8, 10, 12, and 14 and baffle spacing are considered 366.67, 220,157.14, 122.22, 100, and 84.61 respectively with 38% baffle cut are investigated to study the effect of pressure drop and heat transfer coefficient.Shell and tube heat exchanger with single segmental baffles is designed with same input parameters using Kern’s theoretical method and Bell-Delaware method. From the CFD simulation results, heat transfer coefficient and pressure drop values for varying tube layout are provided.Variation of number of baffles with shell side pressure drop heat transfer coefficient are shown. It is discussed that for both methods (analytical calculation and CFD result) pressure drops will be increases with increases number of baffles. K- Standard turbulence model with second order discretization and fine mesh is selected for CFD simulation considered.The result are shown highly sensitive to tube layout orientation selection, it is observed for this heat exchanger geometry 30 tube layout and 14 baffle arrangement gives slightly better results. Keywords : CFD Ansys simulation, Heat transfer coefficient, Pressure drop DOI: 10.7176/IEL/10-3-03 Publication date: November 30 th 2020

An analytical method for spiral-wound heat exchanger: design and cost estimation considering temperature-dependent fluid properties

PurposeSpiral-wound heat exchangers (SWHEs) are widely used in different industries. In special applications, such as cryogenic (HEs), fluid properties may significantly depend on fluid temperature. This paper aims to present an analytical method for design and rating of SWHEs considering variable fluid properties with consistent shell geometry and single-phase fluid.Design/methodology/approachTo consider variations of fluid properties, the HE is divided into identical segments, and the fluid properties are assumed to be constant in each segment. Validation of the analytical method is accomplished by using three-dimensional numerical simulation with shear stress transport k-ω model, and the numerical model is verified by using the experimental data. Moreover, the HE cost is selected as the main criterion in obtaining the proper design, and the most affordable geometry is selected as the proper design.FindingsThe accuracy of different heat transfer and pressure drop correlations is investigated by comparing the analytical and numerical results. The average errors in the calculation of effectiveness, shell-side pressure drop and tube-side pressure drop using the analytical method are 2.1%, 13.9% and 13.3%, respectively. Moreover, the effect of five main geometrical parameters on the SWHE cost is investigated. The results indicate that the effect of longitudinal pitch ratio on the SWHE cost can be neglected, whereas other geometrical parameters have a significant impact on the total cost of the SWHE.Originality/valueThis work contains a versatile and low-cost analytical method to design and rating the SWHEs considering the variable fluid property with consistent shell geometry. The previous studies have introduced complex methods and have not considered the consistency of shell geometry.

Analysing thermal-hydraulic performance and energy efficiency of shell-and-tube heat exchangers with longitudinal flow based on experiment and numerical simulation

In this study, diverse baffled longitudinal flow shell-and-tube heat exchangers (STHX) are contrasted with segmental baffle shell-and-tube heat exchanger (SG-STHX). Experimental data are obtained with municipal water served as the working fluid, and the shell-side volume flow rate ranges from 1.79 m3/h to 7.42 m3/h. The components of the shell-side pressure drop are discussed stand on different flow patterns. The maximum proportion of pressure drop in tube bundle section of rod baffle shell-and-tube heat exchanger (RB-STHX) is 12%, while it has nearly taken up 70% shell-side pressure drop for both SG-STHX and large-and-small hole baffle shell-and-tube heat exchanger (LSHB-STHX). The energy efficiency of three tested STHXs is deliberated from three perspectives, including entropy generation, exergy destruction, and efficiency evaluation criterion. The longitudinal flow pattern performed superior energy efficiency, particularly for RB-STHX with the least irreversible energy loss and the most available work. Grounded on the energy-saving potential of RB-STHX, further numerical simulations on the shell-side thermo-hydraulic performance of RB-STHX are conducted. The nexus between geometrical parameters of RB-STHX and its thermal-hydraulic performance are studied. The thermal-hydraulic performance and energy efficiency discussed in this study support further design and application of longitudinal flow STHX to retain inherent superiorities with advanced performance.