New methodology for the characterisation of thermal performance in a hot water storage tank during charging

Abstract

ElsevierGonzález Altozano, P.; Gasque Albalate, M.; Ibáñez Solís, F.; Gutiérrez-Colomer, RP. (2015). New methodology for the characterisation of thermal performance in a hot water storage tank during charging. Applied Thermal ABSTRACTIn solar water heating systems, the application of certain stratification indices requires the characterisation of the water temperature distribution profile inside the tank and its evolution. In order to avoid the limitations and drawbacks related to the discrete measures provided by experimental trials, this paper presents a newly developed method, called Virtual TC, which allows the water temperature to be estimated at any depth and at any time in a storage tank during the charge process. The proposed methodology can be very useful for estimating the numerous temperature-dependent indices employed for the characterisation and evaluation of thermal stratification in water storage tanks. As a practical example, it was successfully applied to determine the instantaneous temperature profile and thermocline thickness and its evolution throughout charging. It is concluded that the Virtual TC method gives highly satisfactory results under normal operational conditions for a hot water storage tank during the charge cycle.

Simple inlet devices and their influence on thermal stratification in a hot water storage tank

“…8b), particularly for the upper part of the water tank (TC2). This was already reported by [46] when D1-H-exp and D1-L-exp were compared. The beginning of the curves seemed to get closer in all the inlet configurations when low inflow ( Fig.…”

“…The experimental cases E1-H-exp, E1-L-exp, D1-H-exp and D1-L-exp described in [45], [46] and showed in Table 1 were used to validate the model. After validation, three additional configurations based on both geometrical variations of the elbow (E1) and the diffuser (D1), and modifications of the boundary condition or inlet velocity profile were simulated and analysed.…”

“…However, such a study provided only transient temperature data in the thermocouple locations for the experimental trials tested. In addition, the Virtual TC method was proposed by [46] to define the transient temperature profile avoiding the disadvantages related to the availability of discrete temperature data to calculate temperature-dependent indices in thermal stratification. However, hydrodynamics and their relation to stratification could not be examined in such experiments.…”

Thermal performance assessment and improvement of a solar domestic hot water tank with PCM in the mantle

“…They revealed that the vertical orientation design was more efficient than the horizontal one for a stratified storage tank. González-Altozano et al [5] developed a new method called Virtual TC for the thermal performance characterisation in a hot water storage…”

Procesos de Mezcla en Flujos Turbulentos con Técnicas de la Mecánica de Fluidos Computacional (CFD)

“…The experimental cases E1-H-exp, E1-L-exp, D1-H-exp and D1-L-exp described in García-Marí et al (2013) and González-Altozano et al (2015) and showed in Table 3.1 were used to validate the model. After validation, three additional configurations based on both geometrical variations of the elbow (E1) and the diffuser (D1), and modifications of the boundary condition or inlet velocity profile were simulated and analysed.…”