Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers

Musser, A; Bahnfleth, W P

Title: Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers

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Abstract

Temperature profiles in a full-scale, naturally stratified, chilled-water thermal storage tank are described. Tests were performed using a 1.4 million gallon (5,300 m{sup 3}), 44.5 ft (13.56 m) water depth cylindrical tank with radial diffusers. Nine charge and discharge cycle tests were performed for various flow rates, covering and extending beyond the normal operating range of the system. A method for obtaining thermocline thickness from field data was derived, and a relationship between inlet flow rate and initial thermocline thickness was established. Significant differences between profiles obtained for charge and discharge cycles at similar flow rates suggest that the free surface at the top of the tank allows more mixing to occur near the upper diffuser. A study of thermocline growth compares measured temperature profiles with those predicted by a numerical conduction model that uses temperature profiles measured early in the cycle as an initial condition. Comparison with the numerical study shows that, for high flow rate tests, large-scale mixing induced by the inlet diffuser can have significant effects on thermocline development, even after the thermocline has moved away from the inlet diffuser.

Authors:

Musser, A; Bahnfleth, W P ^[1]

Pennsylvania State Univ., University Park, PA (United States). Dept. of Architectural Engineering

Publication Date:: Thu Oct 01 00:00:00 EDT 1998

OSTI Identifier:: 653179

Report Number(s):: CONF-980123-
Journal ID: ISSN 0001-2505; TRN: IM9827%%72

Resource Type:: Conference

Resource Relation:: Conference: 1998 ASHRAE winter meeting, San Francisco, CA (United States), 17-21 Jan 1998; Other Information: PBD: 1998; Related Information: Is Part Of ASHRAE transactions 1998. Volume 104, Part 1A: Technical papers; PB: 834 p.

Country of Publication:: United States

Language:: English

Subject:: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 25 ENERGY STORAGE; THERMAL ENERGY STORAGE EQUIPMENT; COLD STORAGE; TEMPERATURE DISTRIBUTION; COOLING SYSTEMS; DISTRICT COOLING

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                    Musser, A, and Bahnfleth, W P. Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers.  United States: N. p., 1998. 
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                    Musser, A, & Bahnfleth, W P. Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers.  United States.

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                    Musser, A, and Bahnfleth, W P. 1998.  
        "Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers".  United States.

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@article{osti_653179,

  title        = {Evolution of temperature distributions in a full-scale stratified chilled-water storage tank with radial diffusers},

  author       = {Musser, A and Bahnfleth, W P},

  abstractNote = {Temperature profiles in a full-scale, naturally stratified, chilled-water thermal storage tank are described. Tests were performed using a 1.4 million gallon (5,300 m{sup 3}), 44.5 ft (13.56 m) water depth cylindrical tank with radial diffusers. Nine charge and discharge cycle tests were performed for various flow rates, covering and extending beyond the normal operating range of the system. A method for obtaining thermocline thickness from field data was derived, and a relationship between inlet flow rate and initial thermocline thickness was established. Significant differences between profiles obtained for charge and discharge cycles at similar flow rates suggest that the free surface at the top of the tank allows more mixing to occur near the upper diffuser. A study of thermocline growth compares measured temperature profiles with those predicted by a numerical conduction model that uses temperature profiles measured early in the cycle as an initial condition. Comparison with the numerical study shows that, for high flow rate tests, large-scale mixing induced by the inlet diffuser can have significant effects on thermocline development, even after the thermocline has moved away from the inlet diffuser.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/653179},
  journal      = {},

  issn         = {0001-2505},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Oct 01 00:00:00 EDT 1998},

  month        = {Thu Oct 01 00:00:00 EDT 1998}

}

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