Experimental characterisation of a novel heat exchanger for a solar hot water application under indoor and outdoor conditions

Abstract-The present work investigates the enhancement of heat transfer by using different number of circular fins (8, 10, 12, 16, and 20) in double tube counter flow heat exchanger experimentally. The fins are made of copper with dimensions 66 mm OD, 22 mm ID and 1 mm thickness. Each fin has three of 14 mm diameter perforations located at 120o from each to another. The fins are fixed on a straight smooth copper tube of 1 m length, 19.9 mm ID and 22.2 mm OD. The tube is inserted inside the insulated PVC tube of 100 mm ID. The cold water is pumped around the finned copper tube, inside the PVC, at mass flow rates range (0.01019 - 0.0219) kg/s. The Reynold's number of hot water ranges (640 - 1921). The experiment results are obtained using six double tube heat exchanger (1 smooth tube and the other 5 are finned one). The results, illustrated that the heat transfer coefficient proportionally with the number of fin. The results also showed that the enhancement ratio of heat transfer for finned tube is higher than for smooth tube with (9.2, 10.2, 11.1, 12.1 13.1) times for number of fins (8, 10, 12, 16 and 20) respectively.

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Effect of Twisted Fin Array in a Triple-Tube Latent Heat Storage System during the Charging Mode

Sustainability ◽

10.3390/su13052685 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2685

Author(s):

Mohammad Ghalambaz ◽

Jasim M. Mahdi ◽

Amirhossein Shafaghat ◽

Amir Hossein Eisapour ◽

Obai Younis ◽

...

Keyword(s):

Energy Storage ◽

Heat Exchanger ◽

Latent Heat ◽

Thermal Energy ◽

Heat Storage ◽

Hot Water ◽

Melting Time ◽

Latent Heat Storage ◽

Tube Heat Exchanger ◽

Storage Rate

This study aims to assess the effect of adding twisted fins in a triple-tube heat exchanger used for latent heat storage compared with using straight fins and no fins. In the proposed heat exchanger, phase change material (PCM) is placed between the middle annulus while hot water is passed in the inner tube and outer annulus in a counter-current direction, as a superior method to melt the PCM and store the thermal energy. The behavior of the system was assessed regarding the liquid fraction and temperature distributions as well as charging time and energy storage rate. The results indicate the advantages of adding twisted fins compared with those of using straight fins. The effect of several twisted fins was also studied to discover its effectiveness on the melting rate. The results demonstrate that deployment of four twisted fins reduced the melting time by 18% compared with using the same number of straight fins, and 25% compared with the no-fins case considering a similar PCM mass. Moreover, the melting time for the case of using four straight fins was 8.3% lower than that compared with the no-fins case. By raising the fins’ number from two to four and six, the heat storage rate rose 14.2% and 25.4%, respectively. This study presents the effects of novel configurations of fins in PCM-based thermal energy storage to deliver innovative products toward commercialization, which can be manufactured with additive manufacturing.

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Thermal performance of a vertical solar hot water storage tank with a mantle heat exchanger depending on the discharging operation parameters

Solar Energy ◽

10.1016/j.solener.2015.03.045 ◽

2015 ◽

Vol 116 ◽

pp. 184-204 ◽

Cited By ~ 22

Author(s):

Mevlut Arslan ◽

Atila Abir Igci

Keyword(s):

Heat Exchanger ◽

Thermal Performance ◽

Storage Tank ◽

Water Storage ◽

Hot Water ◽

Water Storage Tank ◽

Operation Parameters

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Experimental performance evaluation of a novel heat exchanger for a solar hot water storage system

Applied Energy ◽

10.1016/j.apenergy.2008.11.030 ◽

2009 ◽

Vol 86 (9) ◽

pp. 1492-1505 ◽

Cited By ~ 16

Author(s):

Jayanta Deb Mondol ◽

Mervyn Smyth ◽

Aggelos Zacharopoulos ◽

Trevor Hyde

Keyword(s):

Performance Evaluation ◽

Heat Exchanger ◽

Storage System ◽

Water Storage ◽

Hot Water ◽

Experimental Performance

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Thermal Characteristics Analysis on Multi- Heat Pipe Induced Heat Exchanger

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b1034.1292s219 ◽

2019 ◽

Vol 9 (2S2) ◽

pp. 143-147 ◽

Cited By ~ 1

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.

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Simulation of the effectiveness of longitudinal rectangular fins on the efficiency of the double pipe heat exchanger

Proceedings of the higher educational institutions ENERGY SECTOR PROBLEMS ◽

10.30724/1998-9903-2019-21-4-48-57 ◽

2019 ◽

Vol 21 (4) ◽

pp. 48-57

Author(s):

N. F. Timerbaev ◽

A. K. Ali ◽

Omar Abdulhadi Mustafa Almohamed ◽

A. R. Koryakin

Keyword(s):

Heat Exchanger ◽

Heat Exchangers ◽

Cold Water ◽

Tube Diameter ◽

Hot Water ◽

Outer Tube ◽

Design Parameters ◽

Double Pipe ◽

Central Pipe ◽

Pipe Heat

In this article, a mathematical simulation of a double pipe heat exchanger is carried out, having the longitudinal rectangular fins with the dimension of (2*3*1000) mm, mounted on the outer surface of the inner tube of the heat exchanger. In this paper, the advantage of using of that type of fins and its effect on the effectiveness of the heat exchanger are studied with the help of the computer program. The carried out research allowsmaking the calculation to find the optimum design parameters of heat exchangers. The outer tube diameter is (34.1mm) while the inner tube diameter is (16.05mm). The tubes wall thickness is (1.5mm) and the model length was (1 m). The hot water is flowing through the inner tube in parallel with the cold water that passing the outer tube. The hot and cold water temperature at the inlet is (75°C & 30°C) respectively. The mass flow rate inside the central pipe is (0.1 kg/s) while the annular pipe carrying (0.3 kg/s). In the present work, the program ANSYS Workbench 15.0 was used to find out the results of heat transfer as well as the behavior of liquids inside the heat exchangers.

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Performance Analysis and Design Optimization of Shell and Tube Heat Exchangers

10.21203/rs.3.rs-407371/v1 ◽

2021 ◽

Author(s):

praveen math

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Exchangers ◽

Pressure Loss ◽

Fluid Flows ◽

Hot Water ◽

Flow Conditions ◽

Shell Side ◽

Shell And Tube ◽

Side Flow

Abstract Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. They are also widely used in process applications as well as the refrigeration and air conditioning industry. The robustness and medium weighted shape of Shell and Tube heat exchangers make them well suited for high pressure operations. The aim of this study is to experiment, validate and to provide design suggestion to optimize the shell and tube heat exchanger (STHE). The heat exchanger is made of acrylic material with 2 baffles and 7 tubes made of stainless steel. Hot fluid flows inside the tube and cold fluid flows over the tube in the shell. 4 K-type thermocouples were used to read the hot and cold fluids inlet and outlet temperatures. Experiments were carried out for various combinations of hot and cold water flow rates with different hot water inlet temperatures. The flow conditions are limited to the lab size model of the experimental setup. A commercial CFD code was used to study the thermal and hydraulic flow field inside the shell and tubes. CFD methodology is developed to appropriately represent the flow physics and the procedure is validated with the experimental results. Turbulent flow in tube side is observed for all flow conditions, while the shell side has laminar flow except for extreme hot water temperatures. Hence transition k-kl-omega model was used to predict the flow better for transition cases. Realizable k- epsilon model with non-equilibrium wall function was used for turbulent cases. Temperature and velocity profiles are examined in detail and observed that the flow remains almost uniform to the tubes thus limiting heat transfer. Approximately 2/3 rd of the shell side flow does not surround the tubes due to biased flow contributing to reduced overall heat transfer and increased pressure loss. On the basis of these findings an attempt has been made to enhance the heat transfer by inducing turbulence in the shel l side flow. The two baffles were rotated in opposite direction to each other to achieve more circulation in the shell side flow and provide more contact with tube surface. Various positions of the baffles were simulated and studied using CFD analysis and th e results are summarized with respect to heat transfer and pressure loss.

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Thermal Analysis of the Effects of Multifaceted Conditions on Performance of Shell-and-Tube Heat Exchanger

European Journal of Engineering Research and Science ◽

10.24018/ejers.2021.6.1.2325 ◽

2021 ◽

Vol 6 (1) ◽

pp. 69-75

Author(s):

Taiwo O. Oni ◽

Ayotunde A. Ojo ◽

Daniel C. Uguru-Okorie ◽

David O. Akindele

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Parallel Flow ◽

Hot Water ◽

Inlet Temperature ◽

Fiber Glass ◽

Counter Flow ◽

Tube Heat Exchanger ◽

Shell And Tube ◽

Flow Configurations

A shell-and-tube heat exchanger which was subjected to different flow configurations, viz. counter flow, and parallel flow, was investigated. Each of the flow configurations was operated under two different conditions of the shell, that is, an uninsulated shell and a shell insulated with fiber glass. The hot water inlet temperature of the tube was reduced gradually from 60 oC to 40 oC, and performance evaluation of the heat exchanger was carried out. It was found that for the uninsulated shell, the heat transfer effectiveness for hot water inlet temperature of 60, 55, 50, 45, and 40 oC are 0.243, 0.244, 0.240, 0.240, and 0.247, respectively, for the parallel flow arrangement. For the counter flow arrangement, the heat transfer effectiveness for the uninsulated shell are 2.40, 2.74, 5.00, 4.17, and 2.70%, respectively, higher than those for the parallel flow. The heat exchanger’s heat transfer effectiveness with fiber-glass-insulated shell for the parallel flow condition with tube hot water inlet temperatures of 60, 55, 50, 45, and 40 oC are 0.223, 0.226, 0.220, 0.225, and 0.227, respectively, whereas the counter flow condition has its heat transfer effectiveness increased by 1.28, 1.47, 1.82, 1.11, and 1.18%, respectively, over those of the parallel flow.

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