scholarly journals Experimental Investigation on Triple Concentric Tube Heat Exchanger with Helical Baffles

2020 ◽  
Vol 6 (11) ◽  
pp. 14-20
Author(s):  
Rohit Kumar Gaur ◽  
Dr. Shashi Kumar Jain ◽  
Dr. Sukul Lomash
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Solid Particles ◽  
Tube Heat Exchanger ◽  
High Heat Transfer

A heat exchanger is a device used to transfer thermal energy between two or more liquids, between a solid surface and a liquid, or between solid particles and a liquid at different temperatures and in thermal contact where shell and tube heat exchangers contain a large number of tubes packed in a jacket whose axes are parallel to those of the shell. Heat transfer occurs when one fluid flows into the pipes while the other flows out of the pipes through the jacket. In industry, three-tube heat exchanger tubes are used as condensers, evaporators, sub cooler, heat recovery heat exchangers, etc. The three concentric tube heat exchanger is a constructively modified version of the double concentric tube heat exchanger as an intermediate tube adds some advantages over the double tube heat exchangers in that it is larger tube surface area heat transfer per unit of length.  In the present study, the triple tube heat exchanger is further modified by inserting helical baffle over the surface of one of the tubes and observed turbulence flow which may lead to high heat transfer rates between the fluids of heat exchanger. Further, the Reynolds number, Nusselt number, friction factor of the flow at different mass flow rates of the hot fluid while keeping a constant mass flow rate of cold and normal temperature fluids were calculated. It was found that as the mass flow rate of the fluid increases the Reynolds number increases, the turbulence in the flow will increase which will cause the intermixing of the fluid, higher the rate of intermixing, more will be the heat transfer of the system.  

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.

scholarly journals Experimental Investigation Of Heat Transfer Characteristics Of Nanofluid Using Parallel Flow, Counter Flow And Shell And Tube Heat Exchanger

2015 ◽  
Vol 62 (4) ◽  
pp. 509-522 ◽  
Author(s):  
R. Dharmalingam ◽  
K.K. Sivagnanaprabhu ◽  
J. Yogaraja ◽  
S. Gunasekaran ◽  
R. Mohan
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Heat Exchanger ◽  
Transfer Coefficient ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Tube Heat Exchanger ◽  
Overall Heat Transfer Coefficient ◽  
Shell And Tube

Abstract Cooling is indispensable for maintaining the desired performance and reliability over a very huge variety of products like electronic devices, computer, automobiles, high power laser system etc. Apart from the heat load amplification and heat fluxes caused by many industrial products, cooling is one of the major technical challenges encountered by the industries like manufacturing sectors, transportation, microelectronics, etc. Normally water, ethylene glycol and oil are being used as the fluid to carry away the heat in these devices. The development of nanofluid generally shows a better heat transfer characteristics than the water. This research work summarizes the experimental study of the forced convective heat transfer and flow characteristics of a nanofluid consisting of water and 1% Al2O3 (volume concentration) nanoparticle flowing in a parallel flow, counter flow and shell and tube heat exchanger under laminar flow conditions. The Al2O3 nanoparticles of about 50 nm diameter are used in this work. Three different mass flow rates have been selected and the experiments have been conducted and their results are reported. This result portrays that the overall heat transfer coefficient and dimensionless Nusselt number of nanofluid is slightly higher than that of the base liquid at same mass flow rate at same inlet temperature. From the experimental result it is clear that the overall heat transfer coefficient of the nanofluid increases with an increase in the mass flow rate. It shows that whenever mass flow rate increases, the overall heat transfer coefficient along with Nusselt number eventually increases irrespective of flow direction. It was also found that during the increase in mass flow rate LMTD value ultimately decreases irrespective of flow direction. However, shell and tube heat exchanger provides better heat transfer characteristics than parallel and counter flow heat exchanger due to multi pass flow of nanofluid. The overall heat transfer coefficient, Nusselt number and logarithmic mean temperature difference of the water and Al2O3 /water nanofluid are also studied and the results are plotted graphically.

Effect of flow rates on segmental baffle shell and tube heat exchanger using CuO-W nanofluids

2020 ◽  
Vol 17 (1) ◽  
pp. 115-126 ◽  
Author(s):  
Seralathan Sivamani ◽  
Murugan M. ◽  
Hariram Venkatesan ◽  
Micha Premkumar T.
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Shell Side ◽  
Content Type ◽  
Tube Heat Exchanger ◽  
Fluid Mass ◽  
Shell And Tube

Purpose Nanofluid exhibits higher density, higher viscosity, higher thermal conductivity and reduced specific heat capacity along with improved heat transfer characteristics. It is comparatively better than conventional fluids in terms of thermo-physical properties. This paper aims to investigate experimentally the overall performance of the shell and tube heat exchanger operated under two different configurations – without baffles (STHX_1) and with baffles (STHX_2) using 0.01 Vol.% and 0.02 Vol.% of CuO-W nanofluid. Design/methodology/approach Two different configurations, one without baffles (STHX_1) and other with single segmental baffles (STHX_2), are chosen with all other dimensional details of shell and tube remaining same. Water is used as base fluid. CuO nanoparticle is chosen, as its thermal conductivity is higher compared to other metal oxides. A comparative study on the thermal performance of these shell and tube heat exchangers are performed by considering different Vol.% concentrations of CuO-W nanofluid and the outcome are compared with the base fluid (i.e., water). The influence of varying the mass flow rate of the tube side fluid by keeping shell side fluid mass flow rate as constant and vice versa on the thermal performance of shell and tube heat exchanger are studied. Findings The modified shell and tube heat exchanger with baffles (STHX_2) give an improved performance. The heat transfer coefficient improved by about 11.28 and 7.54 per cent for 0.02 and 0.01 Vol.% of CuO-W nanofluid compared to water. Overall heat transfer coefficient for STHX_2 enhanced between 118.26% to 123.06% in comparison with base fluid for 0.02 Vol.% of CuO-W nanofluid whereas, it improved between 79.20% to 87.51% for 0.01 Vol.% of CuO-W nanofluid. Similarly, the actual heat transfer enhanced between 71.79% to 77.77% and between 48.71% to 55.55% for 0.02 and 0.01 Vol.% of CuO-W nanofluid, respectively. Moreover, mass flow rates of the working fluids significantly influence the performance of the shell and tube heat exchanger. Originality/value Two cases are considered here. first, by varying the shell side fluid mass flow rate and keeping the tube side fluid mass flow rate as constant. Later, tube side fluid mass flow rates are varied and shell side fluid mass flow rate is kept constant. It is found that in Case 2, for both 0.01 and 0.02 Vol.% of CuO-W nanofluid, highest performance is obtained for 150 kg/h of shell side and tube side fluid flows involving STHX_2. Finally, the modified shell and tube heat exchanger with baffle arrangement gives the best performance by using 0.02 Vol.% of CuO-W nanofluid.

scholarly journals Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness

2016 ◽  
Vol 37 (4) ◽  
pp. 137-159 ◽  
Author(s):  
Rafał Andrzejczyk ◽  
Tomasz Muszyński
Keyword(s):  
Heat Transfer ◽  
Surface Modification ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Helical Structure ◽  
Nuclear Industry ◽  
Helical Coil ◽  
Tube Heat Exchanger ◽  
High Heat Transfer ◽  
Coil Heat

Abstract The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow inside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

scholarly journals Analytical and Experimental Investigation of a Plate Fin Heat Exchanger at Cryogenics Temperature

2021 ◽  
Vol 39 (4) ◽  
pp. 1225-1235
Author(s):  
Ajay K. Gupta ◽  
Manoj Kumar ◽  
Ranjit K. Sahoo ◽  
Sunil K. Sarangi
Keyword(s):  
Heat Exchanger ◽  
Pressure Drop ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Cryogenic Temperature ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Compact Size

Plate-fin heat exchangers provide a broad range of applications in many cryogenic industries for liquefaction and separation of gasses because of their excellent technical advantages such as high effectiveness, compact size, etc. Correlations are available for the design of a plate-fin heat exchanger, but experimental investigations are few at cryogenic temperature. In the present study, a cryogenic heat exchanger test setup has been designed and fabricated to investigate the performance of plate-fin heat exchanger at cryogenic temperature. Major parameters (Colburn factor, Friction factor, etc.) that affect the performance of plate-fin heat exchangers are provided concisely. The effect of mass flow rate and inlet temperature on the effectiveness and pressure drop of the heat exchanger are investigated. It is observed that with an increase in mass flow rate effectiveness and pressure drop increases. The present setup emphasis the systematic procedure to perform the experiment based on cryogenic operating conditions and represent its uncertainties level.

scholarly journals Thermal Characteristics Analysis on Multi- Heat Pipe Induced Heat Exchanger

2019 ◽  
Vol 9 (2S2) ◽  
pp. 143-147 ◽  
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Pipe ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cold Water ◽  
Hot Water ◽  
Working Fluid ◽  
Physical Parameters

In this investigation of multi heat pipe induced in heat exchanger shows the developments in heat transfer is to improve the efficiency of heat exchangers. Water is used as a heat transfer fluid and acetone is used as a working fluid. Rotameter is set to measure the flow rate of cold water and hot water. To maintain the parameter as experimental setup. Then set the mass flow rate of hot water as 40 LPH, 60LPH, 80 LPH, 100LPH, 120 LPH and mass flow rate of cold water as 20 LPH, 30 LPH, 40 LPH, 50 LPH, and 60 LPH. Then 40 C, 45 ºC, 50 ºC, 55 C, 60 ºC are the temperatures of hot water at inlet are maintained. To find some various physical parameters of Qc , hc , Re ,, Pr , Rth. The maximum effectiveness of the investigation obtained from condition of Thi 60 C, Tci 32 C and 100 LPH mhi, 60 LPH mci the maximum effectiveness attained as 57.25. Then the mhi as 100 LPH, mci as 60 LPH and Thi at 40 C as 37.6%. It shows the effectiveness get increased about 34.3 to the maximum conditions.

Effect of Mass Flow Rate of Inlet Gas on Holdup Mass of Solidcyclone Heat Exchanger

2014 ◽  
Vol 592-594 ◽  
pp. 1498-1502 ◽  
Author(s):  
T. Mothilal ◽  
K. Pitchandi
Keyword(s):  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
High Efficiency ◽  
Solid Particles ◽  
Operating Parameters ◽  
Water Removal ◽  
Solvent Recovery ◽  
Solid Feed Rate

Effect of mass flow rate of inlet gas on holdup mass in a high efficiency cyclone has been performed. Cyclone as heat transfer equipment may be used for drying, solidification, water removal, solvent recovery, sublimation, chemical reaction and oxidation. In all such cases, performance of cyclone depends on the surface area of the solid particles inside the cyclone. The holdup varies with the variation in operating parameters. This proposed work will present an effect of mass flow rate of inlet gas on cyclone heat exchanger and calculation of holdup mass by varying the mass flow rate of inlet gas, solid feed rate and diameter of the particle.

Transient Response of a Cross Flow Heat Exchanger Subjected to Temperature and Flow Perturbations

2015 ◽  
Author(s):  
Karthik Silaipillayarputhur ◽  
Stephen A. Idem
Keyword(s):  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Cross Flow ◽  
Transient Performance ◽  
Numerical Predictions ◽  
Minimum Capacity ◽  
Flow Heat

The transient performance of a multi-pass cross flow heat exchanger subjected to temperature and mass flow rate perturbations, where the heat exchanger flow circuiting is neither parallel flow nor counter flow, is considered in this work. A detailed numerical study was performed for representative single-pass, two-pass, and three-pass heat exchangers. Numerical predictions were obtained for cases where the minimum capacity rate fluid was subjected to a step change in inlet temperature in absence of mass flow rate perturbations. Likewise, numerical predictions were obtained for the heat exchangers operating initially at steady state, where a step mass flow rate change of the minimum capacity rate fluid was imposed in the absence of any fluid temperature perturbations. The transient performance of this particular heat exchanger configuration subjected to these temperature and flow disturbances has not been discussed previously in the available literature. In the present study the energy balance equations for the hot and cold fluids and the heat exchanger wall were solved using an implicit central finite difference method. A parametric study was conducted by varying the dimensionless quantities that govern the transient response of the heat exchanger over a typical range of values. Because of the storage of energy in the heat exchanger wall, and finite propagation times associated with the inlet perturbations, the outlet temperatures of both fluids do not respond instantaneously. The results are compared with previously published transient performance predictions of multi-pass counter flow and parallel flow heat exchangers.

scholarly journals Heat transfer performance and friction factor of various nanofluids in a double-tube counter flow heat exchanger

2020 ◽  
Vol 24 (6 Part A) ◽  
pp. 3601-3612
Author(s):  
Dan Zheng ◽  
Jin Wang ◽  
Yu Pang ◽  
Zhanxiu Chen ◽  
Bengt Sunden
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Heat Exchanger ◽  
Friction Factor ◽  
Flow Resistance ◽  
Heat Transfer Performance ◽  
Weight Fraction ◽  
Transfer Performance ◽  
Tube Heat Exchanger ◽  
High Heat Transfer

Experimental research was conducted to reveal the effects of nanofluids on heat transfer performance in a double-tube heat exchanger. With nanoparticle weight fraction of 0.5-2.0% and Reynolds number of 4500-14500, the flow resistance and heat transfer were analyzed by using six nanofluids, i.e., CuO-water, Al2O3-water, Fe3O4-water, ZnO-water, SiC-water, SiO2-water nanofluids. Results show that SiC-water nanofluid with a weight concentration of 1.5% provides the best improvement of heat transfer performance. 1.0% CuO-water and 0.5% SiO2-water nanofluids have lower friction factors in the range of Reynolds number from 4500-14500 compared to the other nanofluids. Based on test results of heat transfer performance and flow resistance, the 1.0% CuO-water nanofluid shows a great advantage due to a relatively high heat transfer performance and a low friction factor. Finally, empirical formulae of Nusselt numbers for various nanofluids were established based on experimental data tested in the double-tube heat exchanger.

Heat Transfer Analysis of Shell and Tube Heat Exchanger Cooled Using Nanofluids

2019 ◽  
Vol 12 (4) ◽  
pp. 350-356 ◽  
Author(s):  
Mohammed Kareemullah ◽  
K.M. Chethan ◽  
Mohammed K. Fouzan ◽  
B.V. Darshan ◽  
Abdul Razak Kaladgi ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Zinc Oxide ◽  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Flow Rate ◽  
Base Fluid ◽  
Heat Transfer Analysis ◽  
Tube Heat Exchanger ◽  
Shell And Tube ◽  
Nano Fluids

Background:: In Shell and Tube Heat Exchanger (STHX), heat is exchanged between hot water (coming from industrial outlet by forced convection) to the cold water. Instead of water, if Nano fluids are used into these tubes, then there is a possibility of improved heat transfer because of high thermal conductivity of the nanofluids. Objective:: From many literature and patents, it was clear that the study of STHX using metal oxide nanoparticles is very scarce. Therefore, the objective of the present investigation is to check the thermal performance of STHX operated with zinc oxide nanofluid and compare with water as the base fluid. Methods:: Heat transfer analysis of a shell and tube heat exchanger was carried out experimentally using Zinc oxide as a nanofluid. Mass flow rate on tube side was varied while on the shell side it was kept constant. Various heat transfer parameters like heat transfer coefficient, heat transfer rate effectiveness and LMTD (Log Mean Temperature Difference) were studied. The experimental readings were recorded after the steady-state is reached under forced flow conditions. Results:: It was found that the effectiveness improves with increase in mass flow rate of nanofluids as compared to base fluid. Conclusion:: From the obtained results, it was concluded that heat transfer enhancement and effectiveness improvement does occur with nano fluids but at the cost of pumping power.

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