Effectiveness of the earth tube heat exchanger system coupled to a space model in achieving thermal comfort in rural areas

The main objective of present work to investigate the arrangements of piping system of earth tube heat exchanger for better thermal comfort. For these work CFD analysis on three different designs of earth tube heat exchanger for summer and winter session for Bhopal location have been performed. computational fluid dynamics analysis have been performed on earth tube heat exchanger using horizontal pipe at various air velocity such as 0.5m/sec, 1 m/sec, 2m/sec, 3m/sec, 4m/sec & 5m/sec for summer session, to get temperature distribution inside the earth tube heat exchanger. Results show that there are drop of temperature in summer session range from 318K to 296K and rise of temperature in winter session range from 288K to 296.7K. It has been observed from the results of computational fluid dynamic analysis that the earth tube heat exchanger using horizontal pipe gives better result as compared with vertical and inclined piping arrangement. So it is recommended that the earth tube heat exchanger using horizontal pipe arrangement may be used for better thermal comfort.

Download Full-text

Earth-Air and Earth-Water Heat Exchanger Design for Ventilation Systems in Buildings

2010 14th International Heat Transfer Conference, Volume 4 ◽

10.1115/ihtc14-22459 ◽

2010 ◽

Author(s):

Michel De Paepe ◽

Christophe T’Joen ◽

Arnold Janssens ◽

Marijke Steeman

Keyword(s):

Heat Exchanger ◽

Heat Exchangers ◽

Design Methodology ◽

Energy Use ◽

Polyethylene Tube ◽

Dynamic Simulations ◽

Tube Heat Exchanger ◽

Heat Exchanger Design ◽

The Earth ◽

Software Codes

Earth-air heat exchangers are often used for (pre)heating or (pre)cooling of ventilation air in low energy or passive house standard buildings. Several studies have been published in the passed about the performance of these earth-air heat exchangers [1–8]. Often this is done in relation to the building energy use. Several software codes are available with which the behaviour of the earth-air heat exchanger can be simulated. De Paepe and Janssens published a simplified design methodology for earth-air heat exchangers, based on thermal to hydraulic performance optimisation [7]. Through dynamic simulations and measurements it was shown that the methodology is quite conservative [9–10]. Hollmu¨ller added an earth-air heat exchanger model to TRNSYS [11]. In stead of using earth-air heat exchangers, earth-water heat exchangers are now getting more attention. In this system the ventilation air is indirectly cooled/heated with the water flow in a fin-tube heat exchanger in the inlet of the ventilation channel. The water-glycol mixture transfers heat with the earth by flowing through e.g. a polyethylene tube. In the second part of this paper a design methodology is first derived and then applied to this type of system.

Download Full-text

Optimization of Earth Air Tube Heat Exchanger for Cooling Application Using Taguchi Technique

International Journal of Heat and Technology ◽

10.18280/ijht.380411 ◽

2020 ◽

Vol 38 (4) ◽

pp. 845-862

Author(s):

Saif Nawaz Ahmad ◽

Om Prakash

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Heat Exchanger ◽

Transfer Coefficient ◽

Pipe Material ◽

Ground Heat Exchanger ◽

Tube Heat Exchanger ◽

Overall Heat Transfer Coefficient ◽

The Earth ◽

Inner Diameter

Earth air tube heat exchanger (EATHE) is one of the passive technologies which utilize the earth stored heat (renewable energy) for heating/cooling the buildings. EATHE releases heat to earth for cooling space in summer, making the earth a heat sink and extracts earth-stored energy for heating space in winter and makes the earth a heat source. This paper optimizes the Length of the ground heat exchanger and overall heat transfer coefficient of earth air heat exchanger using the Taguchi technique for cooling application. For this purpose, we select six factors such as installation depth of Pipe (A), Pipe's inner diameter (B), Thermal conductivity of pipe material (C), Inlet air temperature (D), Outlet air temperature (E), Inlet air velocity (F). All these factors are taken at three levels, and we select an L27 orthogonal array for experimental runs. The ground heat exchanger's Length and the overall heat transfer coefficient were then calculated for each experimental run. In the Taguchi method, we find the signal to noise ratio for an optimal combination of all six factors and ANOVA to find the order of influencing parameters and their percentage contributions for both the objective parameters. According to our results, the best combination for all the six factors for ground heat exchanger length and overall heat transfer coefficient were A1B1C3D1E3F1 and A2B3C2D3E1F3, respectively. The highest and lowest influencing factors for ground heat exchanger length were the pipe's inner diameter and the pipe's installation depth with their contribution factors of 69.12 and 0.32%, respectively. In contrast, the highest and lowest influencing factors for the overall heat transfer coefficient were the pipe's inner diameter and thermal conductivity of pipe material with their contribution factors of 75.97and 0%, respectively. Hence the order of influence of all the six factors for both the objective parameters was BEFDCA.

Download Full-text

STUDYING SOME OF THE EARTH TUBE HEAT EXCHANGER AND SOILS PROPERTIES

Misr Journal of Agricultural Engineering ◽

10.21608/mjae.2014.98423 ◽

2014 ◽

Vol 31 (4) ◽

pp. 1621-1636

Author(s):

M. H. Hatem ◽

R. El-Kilani ◽

Matthias Schick ◽

H. R. Elshemy

Keyword(s):

Heat Exchanger ◽

Tube Heat Exchanger ◽

The Earth

Download Full-text

Alternative Methods For Preheating Outdoor Ventilation Air

10.20944/preprints201910.0088.v2 ◽

2019 ◽

Author(s):

Anna Romanska - Zapala Romanska - Zapala ◽

Mark Bomberg ◽

Miroslaw Dechnik ◽

Malgorzata Fedorczak-Cisak ◽

Marcin Furtak

Keyword(s):

Heat Exchanger ◽

Thermal Comfort ◽

Weather Conditions ◽

Integrated System ◽

Alternative Methods ◽

High Humidity ◽

Exterior Wall ◽

Missing Information ◽

The Earth ◽

Air Intake

Growing popularity of smart and integrated buildings requires a review of methods to optimize the preheat of ventilation air. An integrated system permits using heat ex-changers located in the mechanical room or in the future even using an exterior wall as a heat exchanger. One may ask the question how does the earth-air heat exchanger (EAHX) technology fitts into this function. EAHX has many advantages but also has many unanswered questions. Some of the drawbacks are: a possible entry of radon gas, high humidity in the shoulder seasons as well as the need for two different air intake sources with a choice that depends on the actual weather conditions. While in winter, the EAHX may be used continuously to ensure thermal comfort, in other seasons, its operation must be automatically controlled. To generate the missing information about the EAHX technology we reviewed literature and examined two nearly identical EAHX systems, placed either in ground next to the building or under the basement slab. Effectively, the information provided in this paper, shows advantages of merging both these approaches while the EAHX shoud be placed under the house or near the basement foundation.

Download Full-text

CFD Simulation of Helical Shell and Tube Heat Exchanger Using Optimization Techniques

Journal of Engineering Research ◽

10.36909/jer.11985 ◽

2021 ◽

Author(s):

Vivek Singh Parihar ◽

◽

Shrikant Pandey ◽

Rakesh Kumar Malviya ◽

Palash Goyal ◽

...

Keyword(s):

Heat Exchanger ◽

Cfd Simulation ◽

High Heat ◽

Optimization Techniques ◽

Straight Tube ◽

Tube Heat Exchanger ◽

Space Model ◽

High Heat Transfer ◽

Helical Tube ◽

Shell And Tube

The objective of this study is to simulate the performance of helical tube shell and tube heat exchanger with several optimization techniques using computational fluid dynamics CFD. To check the performance of a designed model of heat exchanger various techniques are available. In this study, the various possible model of the heat exchanger to enhance the performance of the device have been designed. Firstly, the straight tube is replaced by helical tube in the heat exchanger and used 10, 12, 14 number of helical baffles with 50% baffle cut. Total ten models have been developed. These models are model-I 4-turns without baffle, model-II 4-turns with 10 number baffles, model-III 5-turns without baffle, model-IV 5-turns with 12 number baffles, model-V 6-turns without baffle, model-VI 6-turns with 10 number baffles 0.083m baffle space, model-VII 6-turns with 12 number 0.083m baffle space, model-VIII 6-turns with 14 number baffles 0.064m baffle space, model-IX 7-turns without baffle, model-X 7-turns with 14 number baffles, different number of baffles and baffle space with 50% baffle cut and used CUO nanofluid model-XI 6-turns with 14 number baffle CUO fluid 0.083m baffle space CFD analysis simulation done on ANSYS FLUENT 18. The simulated result shows that the model XI is approximately 40% more optimized as compared to model-I and approximately 24% than model-VIII. It also found that the high heat transfer obtains with increased number of baffles.

Download Full-text