The Influence of Return Loop Flow Rate on Stratification in a Vertical Hot Water Storage Tank Connected to a Heat Pump Water Heater

2000 ◽  
Vol 21 (2) ◽  
pp. 67-73 ◽  
Author(s):  
J. P. Meyer, P. J. A. Raubenheimer,
Keyword(s):  
Heat Pump ◽  
Flow Rate ◽  
Storage Tank ◽  
Water Storage ◽  
Hot Water ◽  
Water Heater ◽  
Water Storage Tank ◽  
Heat Pump Water Heater

Simulation Optimization and Experiment of R1234-ze on the Heat Pump Water Heater Storage Tank

2014 ◽  
Vol 1051 ◽  
pp. 828-831 ◽  
Author(s):  
Yan Qu ◽  
Fang Wang ◽  
Yu Wang ◽  
Peng Wang ◽  
Tang Li ◽  
...  
Keyword(s):  
Heat Pump ◽  
Storage Tank ◽  
Simulation Optimization ◽  
Water Storage ◽  
System Operation ◽  
Water Heater ◽  
Water Storage Tank ◽  
Heat Pump Water Heater ◽  
Fluent Software ◽  
The Stability

Using fluent software simulations to analysis the temperature field and the velocity field of the equal and changing diameter condensing coils at different positions of heat pump water storage tank, and made experiment of R1234-ze on the heat pump water heater storage tank with equal and changing diameter condensing coils ,experimental analysis and simulation results show that changing diameter condensing coils make the tank temperature raise stability, which is beneficial to the stability of the system operation.

A Sustainable Trigeneration System for Residential Applications

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Azzam Abu-Rayash ◽  
Ibrahim Dincer
Keyword(s):  
Heat Pump ◽  
Storage Tank ◽  
Renewable Energy Sources ◽  
Water Storage ◽  
Hot Water ◽  
Low Grade ◽  
High Grade ◽  
Pump System ◽  
Water Storage Tank ◽  
Energy And Exergy

Abstract This paper features the integration of two renewable energy sources, making a new trigeneration system for residential applications. The system is primarily powered by solar photovoltaic-thermal (PVT) along with geothermal energy. This trigeneration system consists of a ground source heat pump, solar system, high-grade and low-grade heat exchangers, a heat pump system, and a water storage tank (WST). The objective of this system is to provide the main commodities for residential use including domestic hot water (DHW), electricity, and space heating. The system is analyzed energetically and exergetically using thermodynamic-based concepts. The overall energy and exergy efficiencies of the proposed system are found to be 86.9% and 74.7%, respectively. In addition, the energy and exergy efficiencies of the PVT system are obtained to be 57.91% and 34.19%, respectively. The exergy destructions at the high-grade heat exchanger and the water storage tank add up to 36.9 kW, which makes up 80% of the total exergy destruction of the system. Additionally, parametric studies are conducted to evaluate the degree of impact that various important parameters have on the overall system performance.

Experimental and Theoretical Investigation of Mixed and Stratified Hot Water Storage Tanks

1988 ◽  
Vol 202 (3) ◽  
pp. 187-193 ◽  
Author(s):  
P P Votsis ◽  
S A Tassou ◽  
D R Wilson ◽  
C J Marquand
Keyword(s):  
Heat Pump ◽  
Storage Tank ◽  
Dynamic Models ◽  
Water Storage ◽  
Pump Energy ◽  
Hot Water ◽  
Pump System ◽  
Heat Pump System ◽  
Water Storage Tank ◽  
Major Factors

This paper investigates the performance of a 1.1 m3 stratified hot water storage tank coupled to a vapour compression heat pump system. A comprehensive data acquisition system has been used to obtain the experimental data from a series of static and dynamic tests. In the static experiments a well-defined thermocline has been achieved and the effects of insulation and tank wall thickness on the preservation of the thermocline have been determined. The results indicate that thermal losses in stratified tanks are about 22 per cent higher than the losses in fully mixed tanks. The dynamic experiments have been conducted with an upward-moving thermocline and the major factors influencing its stability have been correlated in terms of the Archimedes number (Gr/Re2). It has been found that good stratification performance can be maintained with Archimedes numbers in the range between 35000 and 55000. A simplified one-dimensional model of the storage tank has been developed and validated against experimental results. The model will be linked to dynamic models of the heat pump and the building to simulate the performance of a heat store/heat pump energy management system.

Evaluation of Thermal Stratification Inside a New Model of Spherical Water Storage Tank Using a Computational Fluid Dynamics 6 Degrees of Freedom Solver

2019 ◽  
Vol 12 (3) ◽  
Author(s):  
Mohamed Taher Bouzaher ◽  
Belghar Noureddine ◽  
Charaf-Eddine Bensaci ◽  
Nora Bouchahm ◽  
Belhi Guerira
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Flow Rate ◽  
Storage Tank ◽  
Cold Water ◽  
Fluid Dynamic ◽  
Water Storage ◽  
Hot Water ◽  
Computational Domain ◽  
Water Storage Tank

Abstract In this work, a computational analysis of a spherical solar hot water storage tank during the discharging process is carried out by using the commercial code ansys-fluent.15. The study investigates a new type of spherical heat storage tank. A hinged baffle is fixed at the tank vertical axis to increase the discharge flow rate without a thermocline layer. The dynamic mesh LAYERING technique is used to update the computational domain during the movement of the hinged baffle. The passive pitching of the submerged baffle is due to the fluid-dynamic loads. This model limits the mixture between hot and cold water regardless of the inlet flow rate. A comparative study between tanks with typical diffusers and the hinged baffle model is considered. The comparison of the computational fluid dynamics results with available experimental data showed a good agreement. Examinations of the temperature contours indicate that for the typical models, the interaction between the incoming cold water and the stored hot water gives rise to a thick thermocline layer where its temperature and thickness are related to the intensity of the mixing process. The suggested model shows high stratification efficiency along the discharging process.

scholarly journals Analysis of nodalization effects on the prediction error of generalized finite element method used for dynamic modeling of hot water storage tank

2015 ◽  
Vol 36 (3) ◽  
pp. 123-138 ◽  
Author(s):  
Marcin Wołowicz ◽  
Jakub Kupecki ◽  
Katarzyna Wawryniuk ◽  
Jarosław Milewski ◽  
Konrad Motyliński
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Flow Rate ◽  
Prediction Error ◽  
Storage Tank ◽  
Water Storage ◽  
Hot Water ◽  
Generalized Finite Element Method ◽  
Water Storage Tank ◽  
Generalized Finite Element

Abstract The paper presents dynamic model of hot water storage tank. The literature review has been made. Analysis of effects of nodalization on the prediction error of generalized finite element method (GFEM) is provided. The model takes into account eleven various parameters, such as: flue gases volumetric flow rate to the spiral, inlet water temperature, outlet water flow rate, etc. Boiler is also described by sizing parameters, nozzle parameters and heat loss including ambient temperature. The model has been validated on existing data. Adequate laboratory experiments were provided. The comparison between 1-, 5-, 10- and 50-zone boiler is presented. Comparison between experiment and simulations for different zone numbers of the boiler model is presented on the plots. The reason of differences between experiment and simulation is explained.

Energy-saving analysis of air source heat pump integrated with a water storage tank for heating applications

2020 ◽  
Vol 180 ◽  
pp. 107029
Author(s):  
Pin Wu ◽  
Zhichao Wang ◽  
Xiaofeng Li ◽  
Zhaowei Xu ◽  
Yingxia Yang ◽  
...  
Keyword(s):  
Energy Saving ◽  
Heat Pump ◽  
Storage Tank ◽  
Water Storage ◽  
Water Storage Tank ◽  
Air Source Heat Pump

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

Energies ◽  
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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