Numerical Studies on Convergent Tube-in-Tube Heat Exchanger

2015 ◽  
Vol 787 ◽  
pp. 62-66
Author(s):  
M. Ajai Thangaswami ◽  
S.R. Arjun ◽  
M.K. Easwar ◽  
M. Suresh
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Cold Working ◽  
Heat Energy ◽  
Working Fluid ◽  
Simple Modification ◽  
Tube Heat Exchanger ◽  
Numerical Studies ◽  
Transfer Equations ◽  
External Tube

HHeat exchangers have been used since the start of industrialisation, and since then have been modified in a plethora of complex and intricate ways to suit the needs of the corresponding application, but in this paper a simple modification on the existing design has been investigated numerically, which has proven to be effective. A standard tube-in-tube heat exchanger has been modified such that the external tube tapers (converges) to a smaller diameter. The inner tube carries the cold working fluid which absorbs the heat energy carried by the fluid in the outer tube. A numerical simulation has been carried out, taking into account the mass flow rate, fluid temperatures, heat transfer etc., which are governed by fundamental heat transfer equations. The results of the simulation are used to analyse the effect of this modification (convergent tube) on the efficiency of the heat exchanger, which has been found to increase significantly along with the rate of heat transfer.

scholarly journals Numerical Analysis for Heat Transfer Augmentation in a Circular Tube Heat Exchanger Using a Triangular Perforated Y-Shaped Insert

Fluids ◽  
2021 ◽  
Vol 6 (7) ◽  
pp. 247
Author(s):  
Lokesh Pandey ◽  
Satyendra Singh
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Friction Factor ◽  
Circular Tube ◽  
Tube Wall ◽  
Constant Heat Flux ◽  
Working Fluid ◽  
Tube Heat Exchanger ◽  
Heat Transfer Augmentation ◽  
Plain Tube

The present investigation constitutes CFD analysis of the heat transmission phenomenon in a tube heat exchanger with a Y-shaped insert with triangular perforation. The analysis is accomplished by considering air as a working fluid with a Reynolds number ranging from 3000 to 21,000. The segment considered for analysis consists of a circular tube of 68 mm diameter and 1.5 m length. The geometrical parameter considered is the perforation index (0%, 10%, 20%, and 30%). The constant heat flux is provided at the tube wall and a pressure-based solver is used for the solution. The studies are performed for analyzing the effects of inserts on the heat transfer and friction factor in the circular tube heat exchanger which results in augmented heat transfer at a higher perforation index (PI) and lower friction factor. The investigation results show that the highest heat transfer is 5.84 times over a simple plain tube and the maximum thermal performance factor (TPF) is 3.25 at PI = 30%, Re = 3000.

scholarly journals Investigation on fluid flow heat transfer and frictional properties of Al2O3 nanofluids used in shell and tube heat exchanger

2020 ◽  
Author(s):  
sreejesh S R chandran ◽  
Debabrata Barik ◽  
ANSALAM RAJ T G ◽  
Reby ROY
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Transfer Rate ◽  
Working Fluid ◽  
Flow Properties ◽  
Counter Flow ◽  
Tube Heat Exchanger ◽  
Frictional Properties ◽  
Flow Heat ◽  
Shell And Tube

Abstract Nanofluids are generally utilized in providing cooling, lubrication phenomenon, controlling the thermophysical properties of the working fluid. In this work, nanoparticles of Al2O3 are added to the base fluid which flows through the counter flow arrangement in a turbulent flow condition. The hot and cold fluids used are ethylbenzene and water respectively and have different velocities on both shell and tube side. This study emphasizes the analysis of flow properties, friction loss, and energy transfer in terms of heat using nanofluid in the heat exchanger. The heat transfer rate of present investigation with nanoparticle addition is 4.63% higher in comparision to Dittus Boelter correlation. Apart from this, the obtained friction factor is 0.0376 very much closer to Gnielinski and Blasius correlations. This investigation proved that appropriate nanoparticle additions and baffle inclinations have fabulous impact upon the performance of heat exchanger and its effectiveness.

scholarly journals Design and Analysis of double- stacked Heat Exchanger for Brewery Application

2020 ◽  
Vol 9 (1) ◽  
pp. 1793-1798
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Pressure Drop ◽  
Heat Transfer Rate ◽  
Flow Rate ◽  
Transfer Rate ◽  
Working Fluid ◽  
Support Weight ◽  
Tube Heat Exchanger ◽  
Shell And Tube

A heat exchanger is a device intensively used for enhancing the transfer of heat energy between two or more working fluids at different temperature, which are in thermal contact. The optimal design and efficient operation of heat exchanger and heat transfer network are of a great significance in any of the process industry. The heat transfer efficiency depends on both design of heat exchanger and property of working fluid. From various types of heat exchanger, the double stacked shell and tube heat exchanger with straight tube and single pass is to be under study. Here the redesign of heat exchanger takes place with the key objectives of optimizing the pressure drop, optimizing the heat transfer rate and reducing the saddle support weight used for cooling purpose in brewery application. The design calculations are carried out using the Kerns and Bell Delwar method and other important parameters dealing with material selection and geometries are also taken into consideration. FEA analysis for optimizing the saddle support weight is carried out using Dassault systeme’s Solidworks while the CFD analysis for optimizing pressure drop and heat transfer rate is carried out using Dassault systeme’s Solidworks analysis software and the design and working of Shell and tube heat exchanger is determined in terms of variables such as pressure ,temperature ,mass flow rate ,flow rate ,energy input output that are of particular interest in Shell and tube heat exchanger analysis.

scholarly journals Nanofluid-Enhancing Shell and Tube Heat Exchanger Effectiveness with Modified Baffle Architecture

2021 ◽  
Author(s):  
I Made Arsana ◽  
Ruri Agung Wahyuono
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Exchanger ◽  
Heat Transfer Process ◽  
Working Fluid ◽  
Architectural Geometry ◽  
Tube Heat Exchanger ◽  
Heat Exchanger Design ◽  
Shell And Tube ◽  
Efficient Heat Transfer

As shell and tube heat exchanger is widely employed in various field of industries, heat exchanger design remains a constant optimization challenge to improve its performance. The heat exchanger design includes not only the architectural geometry of either the shell and tube configuration or the additional baffles but also the working fluid. The baffle design including the baffle angle and the baffle distance has been understood as key parameter controlling the overall heat exchanger effectiveness. In addition, a room of improvement is open by substituting the conventional working fluid with the nanomaterials-enriched nanofluid. The nanomaterials, e.g. Al2O3, SiO2, TiO2, increases the thermal conductivity of the working fluids, and hence, the more efficient heat transfer process can be achieved. This chapter provide an insight on the performance improvement of shell and tube heat exchanger by modifying the baffle design and utilizing nanofluids.

CFD Analysis of a Shell and Tube Heat Exchanger with Single Segmental Baffles

2020 ◽  
Vol 17 (2) ◽  
pp. 7890-7901
Author(s):  
S. Mohanty ◽  
R. Arora
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Heat Exchanger ◽  
Pressure Drop ◽  
Transfer Coefficient ◽  
Turbulence Models ◽  
Working Fluid ◽  
Ansys Fluent ◽  
Tube Heat Exchanger ◽  
Shell And Tube

In this investigation, a comprehensive approach is established in detail to analyse the effectiveness of the shell and tube heat exchanger (STE) with 50% baffle cuts (Bc) with varying number of baffles. CFD simulations were conducted on a single pass and single tube heat exchanger(HE) using water as working fluid. A counterflow technique is implemented for this simulation study. Based on different approaches made on design analysis for a heat exchanger, here, a mini shell and tube exchanger (STE) computational model is developed. Commercial CFD software package ANSYS-Fluent 14.0 was used for computational analysis and comparison with existing literature in the view of certain variables; in particular, baffle cut, baffle spacing, the outcome of shell and tube diameter on the pressure drop and heat transfer coefficient. However, the simulation results are more circumscribed with the applied turbulence models such as Spalart-Allmaras, k-ɛ standard and k-ɛ realizable. For determining the best among the turbulence models, the computational results are validated with the existing literature. The proposed study portrays an in-depth outlook and visualization of heat transfer coefficient and pressure drop along the length of the heat exchanger(HE). The modified design of the heat exchanger yields a maximum of 44% pressure drop reduction and an increment of 60.66% in heat transfer.

Numerical investigation of Heat Transfer Enhancement in Circular Tube using Twisted Tape Inserts and Nanotechnology

2017 ◽  
Vol 5 (2) ◽  
pp. 42-54
Author(s):  
Najim Abid Jassim ◽  
Kamel Abdul Hussin ◽  
Noor Yahya Abdul Abbass
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Chemical Engineering ◽  
Working Fluid ◽  
Width Ratio ◽  
Twisted Tape ◽  
Tube Heat Exchanger ◽  
First Case ◽  
Plain Tube ◽  
Shell And Tube

In the present work the analysis of three different width ratio of twisted tape in a shell and tube heat exchanger done by ANSYS FLUINT14.0. Heat exchanger type shell and tube have been widely used in industrial application such as refrigeration and environment protection, electrical power generation and chemical engineering. This work deals with the theoretical investigation, which was to evaluate the benefit of changing the width of twisted tape in the heat exchanger and the improving the heat transfer by using water as the working fluid in the first case, then using Nano fluids as a heat transfer working fluid. From the use of the condition in table (1) the simulation shows results of enhancement in heat transfer rate ranging from (53.24% to 55.55%) at width ratio 0.71, (53.62% to 56.09%) at width ratio 0.854 and (52.44% to 57.17%) at width ratio 1, for plain tube with twisted tape with respect to plain tube without twisted tape by using water as cooling fluid. By using Nano- fluid (AL2O3) the enhancement in heat transfer is (69.14% to 60.44%) at width ratio 0.71, (58.36% to 61.51%) at width ratio 0.854 and (56.76% to 63.35%) at width ratio1, for plain tube with twisted tape with respect to plain tube without twisted tape.

Effectiveness of a shell and helically coiled tube heat exchanger operated with gold nanofluids at low concentration: A multi-level factorial analysis

2020 ◽  
pp. 1-39
Author(s):  
Marina B. Fogaça ◽  
Daniele Toniolo Dias ◽  
Sergio L. Gómez ◽  
Jhon Jairo Ramirez Behainne ◽  
Rozane de Fátima Turchiello
Keyword(s):  
Heat Transfer ◽  
Gold Nanoparticles ◽  
Heat Exchanger ◽  
Volumetric Flow Rate ◽  
Working Fluid ◽  
Inlet Temperature ◽  
Coiled Tube ◽  
Tube Heat Exchanger ◽  
Helically Coiled Tube ◽  
Multi Level

Abstract This work assesses the thermal performance of gold nanofluids as cooling liquid in a shell and helically coiled tube (SHCT) heat exchanger built in bench-scale. Tests planned under a multi-level factorial experimental design were carried out to evaluate the effects caused by the volumetric fraction of the gold nanoparticles, the volumetric flow rate of the working fluid and the inlet temperature of the hot fluid (water) on the SHCT heat exchanger effectiveness. Spherical gold nanoparticles with mean diameter of 14±2 nm were produced from the Turkevich's method to be used in two concentrations of about 10-5 %vol. The heat transfer tests were performed at volumetric flow rates of 20, 30 and 40 L/h for both working fluids using heated water at inlet temperatures of 40, 50 and 60°C. Results showed that the less concentrated nanofluid was comparatively more efficient, suggesting the presence of a range of values of the gold concentration for the existence of an improvement on the effectiveness in the heat transfer.

scholarly journals Experimental Investigation and Comparison of Shell Tube and Plate Heat Exchanger used in Water Chillers

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Shamkuwar S.C ◽  
◽  
Nitin Chopra ◽  
Mihir Kulkarni ◽  
Nikhil Ahire ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Plate Heat Exchanger ◽  
Working Fluid ◽  
Plate Heat ◽  
Tube Heat Exchanger ◽  
Overall Heat Transfer Coefficient ◽  
Shell And Tube

The main objective of the paper is to compare the performance of Shell and tube heat exchanger (STHE) and Plate heat exchanger (PHE) used in chillers. The paper deals with experimental investigation and comparison, which is based on actual testing of STHE and PHE. Both heat exchangers were designed and tested for a heat load of 6000 kcal/hr. In both types of heat exchangers, the primary working fluid used is Refrigerant R22 and secondary working fluid used is water. Theoretical analysis shows that PHE has a 9.67 % less heat transfer area than STHE. Experimental results show that overall heat transfer coefficient (OHTC) for PHE is higher than STHE by 30.96%. The paper also includes a comparison of the heat transfer rate (Q) of the two heat exchangers experimentally.

scholarly journals Simulation of shell and tube heat exchanger using COMSOL software

2021 ◽  
Vol 947 (1) ◽  
pp. 012008
Author(s):  
Trung Kim Nguyen ◽  
Tuan Nguyen Ba ◽  
Pha Bui Ngoc ◽  
Abdul Mutalib Embong ◽  
Ngoc Nguyen Thi Nhu ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Conclusive Evidence ◽  
Pressure Drops ◽  
Tube Heat Exchanger ◽  
Water Flows ◽  
Proposed Model ◽  
Transfer Equations ◽  
Shell And Tube ◽  
Good Agreement

Abstract The aim of this paper is to propose a model to simulate the behaviour of water flows in shell and tube heat exchanger. Particularly, the continuity equation, the general heat transfer equations and the energy equation in COMSOL Multiphysics software were implemented in the numerical modelling. Besides, the experiment was also conducted to validate the proposed COMSOL model. The water temperature at locations close to the inlet and outlet of the shell side was respectively predicted at 31.5°C and 34.6°C in the simulation, and it was respectively measured at 31.5°C and 35°C in the experiment. These findings showed that the simulation results had a good agreement with the experiment. Next, this model was extended to simulate the overall heat coefficient and the pressure drops of the water flows in such heat exchanger. The overall heat coefficient was at 736.62 W/m2K. The pressure drops at the inlet/outlet areas of the shell and tubes were at 849.93 Pa and 6255.50 Pa, respectively. Conclusive evidence showed that the proposed model is a reliable method for studying the heat transfer behaviour of the shell and heat exchanger.

scholarly journals Experimentation on Augmenting Heat Transfer Characteristics of (Ethylene Glycol + Water) Mixture in A Combined (Pipe in Pipe and Shell & Tube) Heat Exchanger

2019 ◽  
Vol 8 (3) ◽  
pp. 4442-4449
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Working Fluid ◽  
Counter Flow ◽  
Tube Heat Exchanger ◽  
Overall Heat Transfer Coefficient

In this research work, the design of pipe in pipe, shelland-tube and combined heat exchanger (previously mentioned types were combined to consider as one unit) has been made. These three heat exchangers have been utilized for two kinds of flows i.e., parallel as well counter flow types individually. The design of combined heat exchanger takes been proposed with the idea of increasing the heat transfer area and to understand the behavior of various parameters involved by comparing with the individual heat exchangers. 75:25 aqueous Ethylene Glycols, have been used as the working fluid in all three heat exchangers of counter as well parallel flow conditions. Total quantity of working fluid is 12 liters, in which 6liters of fluid is used as cold fluid and the other half is used as hot fluid. As a result, overall heat transfer coefficient (U) has been increased with increase of mass flow rate. Highest overall heat transfer coefficient value observed as 1943w/m2 -k at highest mass flow rate (within the considerations of this work) of 0.145 kg/s. The highest decrement in LMTD recorded for 0.0425 to 0.145 increase of mass flow rate is 49.32% in shell-and-tube heat exchanger of parallel flow arrangement. The highest effectiveness is observed for pipe in pipe counter flow heat exchanger case, which is 0.39 at a mass flow rate of 0.145kg/s.

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