Design and cost evaluations of solar energy and waste heat utilization systems with latent thermal storage unit using form-stable high-density polyethylene.

A latent thermal storage unit of 30 kWh using form-stable high density polyethylene (HDPE) rods has been developed mainly for solar thermal applications, and heat transfer experiments have been carried out. A direct contact heat transfer technique between HDPE rods and ethylene glycol (EG: a heat transfer fluid) is adopted. Charge and discharge characteristics have been obtained for various thermal input/output and different initial temperature profiles in the storage unit. The direct contact heat transfer and a formation of a clear thermocline provide a good performance for all the cases. Discussions are given of thermal efficiency, storage density, and thermal insulation.

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Latent Thermal Storage Unit Using Form-Stable High Density Polyethylene; Part II: Numerical Analysis of Heat Transfer

Journal of Solar Energy Engineering ◽

10.1115/1.3268108 ◽

1986 ◽

Vol 108 (4) ◽

pp. 290-297 ◽

Cited By ~ 12

Author(s):

M. Kamimoto ◽

Y. Abe ◽

K. Kanari ◽

Y. Takahashi ◽

T. Tani ◽

...

Keyword(s):

Heat Transfer ◽

Computer Simulation ◽

Numerical Analysis ◽

High Density Polyethylene ◽

Thermal Storage ◽

High Density ◽

Storage Unit ◽

Discharge Characteristics ◽

One Dimensional ◽

Finite Difference Equations

Heat transfer in the latent thermal storage unit using form-stable high density polyethylene rods has been numerically analyzed. The analysis is based on simple explicit one-dimensional finite difference equations. The calculation can well simulate both the charge and discharge characteristics of the prototype storage unit developed by the present authors. The computer simulation has been used also to speculate the performance of the storage unit under various conditions. Effects of several parameters on the discharge characteristics have been quantitatively made clear.

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Improvement of the Performance of Solar Energy or Waste Heat Utilization Systems by Using Phase-Change Slurry as an Enhanced Heat-Transfer Storage Fluid

Journal of Solar Energy Engineering ◽

10.1115/1.3267683 ◽

1985 ◽

Vol 107 (3) ◽

pp. 229-236 ◽

Cited By ~ 68

Author(s):

K. E. Kasza ◽

M. M. Chen

Keyword(s):

Heat Transfer ◽

Solar Energy ◽

Phase Change ◽

Single Phase ◽

Waste Heat ◽

Storage Tanks ◽

Enhanced Heat Transfer ◽

Heat Utilization ◽

Waste Heat Utilization ◽

Pumping Rates

This paper is concerned with the benefits of using phase-change slurries as enhanced heat-transfer/storage working fluids in solar energy and waste heat utilization systems. Literature is cited to show that a slurry containing a phase-change material as the dispersed phase promises to have much higher heat-transfer coefficients than conventional single-phase working fluids. Because of the latent heat, the phase-change slurry also requires lower pumping rates and smaller storage tanks than single-phase fluids for the same energy content. These benefits are documented by comparisons of temperature drops, pumping rates, pumping powers, and the sizes of storage tanks for a generic energy collection system operating with and without a slurry.

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