MODIFIED ELECTRICALLY HEATED HOT WATER STORAGE TANK: EXPERIMENTAL INVESTIGATION

Hot water in residential buildings accounts for 37% of the energy used. In hot water storage tanks (HWST) the average water temperature decreases due to turbulent mixing. A modified design of HWSTs to extend hot water availability is proposed and tested. For this purpose two electrically heated 50 litre commercial tanks were obtained. One was equipped with a semidome to inhibit turbulent mixing. The unmodified was used for comparison. These were tested for three flow rates: 6, 8, and 10 L/min. Higher flow rates of hot water temperatures were obtained from the modified tank. To increase the heating transfer rate fins were added to the electrical heater. Water supply temperature of (60°C) was achieved 12 minutes earlier in the modified tank due to extended heat transfer area.

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The Effect of Obstacle Geometry and Position on Thermal Stratification in Solar Hot Water Storage Tanks

Heat Transfer: Volume 3 ◽

10.1115/ht2008-56040 ◽

2008 ◽

Cited By ~ 1

Author(s):

Necdet Altuntop ◽

Veysel Ozceyhan ◽

Yusuf Tekin ◽

Sibel Gunes

Keyword(s):

Storage Tank ◽

Thermal Stratification ◽

Water Storage ◽

Hot Water ◽

Storage Tanks ◽

Domestic Hot Water ◽

Water Storage Tank ◽

Temperature Distributions ◽

Solar Powered ◽

Obstacle Geometry

In this study the effect of obstacle geometry and its position on thermal stratification in solar powered domestic hot water storage tanks are numerically investigated. The goal of this study is to obtain higher thermal stratification and supply hot water for usage as long as possible. The temperature distributions are presented for three different obstacle geometries (1, 2 and 3) and six different distances (f = 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8 mm) from the bottom of the hot water storage tank. The numerical method is validated using both experimental and numerical results available in the literature. It is observed from the results that the thermal stratification increases with the increasing obstacle distance from the bottom of the hot water storage tank for obstacle 1 and 3. The obstacle 2 provides less thermal stratification than the obstacles 1 and 3. As a result, in a duration of 30 minutes, the obstacle 3 provides the best thermal stratification for the distance of f = 0.8 mm from the bottom of the hot water storage tank.

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Experimental investigation of the inflow conditions for a thermally stratified hot water storage tank

Proceedings of the International Symposium on Turbulence, Heat and Mass Transfer ◽

10.1615/ichmt.2006.turbulheatmasstransf.520 ◽

2006 ◽

Author(s):

E. Drapala ◽

J. Buehl ◽

A. Nilius

Keyword(s):

Experimental Investigation ◽

Storage Tank ◽

Water Storage ◽

Hot Water ◽

Water Storage Tank ◽

Inflow Conditions

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SCALE PREVENTION IN A HOT-WATER STORAGE TANK WITH A MAGNETIC PHYSICAL WATER TREATMENT DEVICE

Proceedings of the International Thermal Science Seminar Bled. Volume 1 ◽

10.1615/ichmt.2000.thersieprocvol2thersieprocvol1.390 ◽

2000 ◽

Author(s):

Josua Meyer ◽

Christo Smith ◽

Paul P. Coetzee

Keyword(s):

Water Treatment ◽

Storage Tank ◽

Water Storage ◽

Hot Water ◽

Water Storage Tank ◽

Physical Water Treatment

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The effect of household storage tanks/vessels and user practices on the quality of water: a systematic review of literature

ENVIRONMENTAL SYSTEMS RESEARCH ◽

10.1186/s40068-021-00221-9 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Musa Manga ◽

Timothy G. Ngobi ◽

Lawrence Okeny ◽

Pamela Acheng ◽

Hidaya Namakula ◽

...

Keyword(s):

Systematic Review ◽

Water Quality ◽

Storage Tank ◽

Grey Literature ◽

Water Storage ◽

Storage Tanks ◽

Water Storage Tank ◽

Hygiene Practices ◽

Quality Of Water ◽

Vessel Material

Abstract Background Household water storage remains a necessity in many communities worldwide, especially in the developing countries. Water storage often using tanks/vessels is envisaged to be a source of water contamination, along with related user practices. Several studies have investigated this phenomenon, albeit in isolation. This study aimed at developing a systematic review, focusing on the impacts of water storage tank/vessel features and user practices on water quality. Methods Database searches for relevant peer-reviewed papers and grey literature were done. A systematic criterion was set for the selection of publications and after scrutinizing 1106 records, 24 were selected. These were further subjected to a quality appraisal, and data was extracted from them to complete the review. Results and discussion Microbiological and physicochemical parameters were the basis for measuring water quality in storage tanks or vessels. Water storage tank/vessel material and retention time had the highest effect on stored water quality along with age, colour, design, and location. Water storage tank/vessel cleaning and hygiene practices like tank/vessel covering were the user practices most investigated by researchers in the literature reviewed and they were seen to have an impact on stored water quality. Conclusions There is evidence in the literature that storage tanks/vessels, and user practices affect water quality. Little is known about the optimal tank/vessel cleaning frequency to ensure safe drinking water quality. More research is required to conclusively determine the best matrix of tank/vessel features and user practices to ensure good water quality.

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Minimum Number of Experimental Data for the Thermal Characterization of a Hot Water Storage Tank

Energies ◽

10.3390/en14164741 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4741

Author(s):

María Gasque ◽

Federico Ibáñez ◽

Pablo González-Altozano

Keyword(s):

Experimental Data ◽

Water Temperature ◽

Temperature Profile ◽

Storage Tank ◽

Water Storage ◽

Hot Water ◽

Experimental Temperature ◽

Inlet Temperature ◽

Water Storage Tank ◽

Minimum Number

This paper demonstrates that it is possible to characterize the water temperature profile and its temporal trend in a hot water storage tank during the thermal charge process, using a minimum number of thermocouples (TC), with minor differences compared to experimental data. Four experimental tests (two types of inlet and two water flow rates) were conducted in a 950 L capacity tank. For each experimental test (with 12 TC), four models were developed using a decreasing number of TC (7, 4, 3 and 2, respectively). The results of the estimation of water temperature obtained with each of the four models were compared with those of a fifth model performed with 12 TC. All models were tested for constant inlet temperature. Very acceptable results were achieved (RMSE between 0.2065 °C and 0.8706 °C in models with 3 TC). The models were also useful to estimate the water temperature profile and the evolution of thermocline thickness even with only 3 TC (RMSE between 0.00247 °C and 0.00292 °C). A comparison with a CFD model was carried out to complete the study with very small differences between both approaches when applied to the estimation of the instantaneous temperature profile. The proposed methodology has proven to be very effective in estimating several of the temperature-based indices commonly employed to evaluate thermal stratification in water storage tanks, with only two or three experimental temperature data measurements. It can also be used as a complementary tool to other techniques such as the validation of numerical simulations or in cases where only a few experimental temperature values are available.

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