Abstract A numerical study is made of the behaviour of packed beds containing adsorbent material used for energy storage. The basic model assumes that air at a given absolute humidity and at either a high or low temperature is available to charge or discharge the store, the air flow direction for the charging case being opposed to that for the discharging case. When air flows through the bed, transfer of heat and water vapour to the air stream is assumed to teh governed by surface transfer coefficients, while difusion of heat and water vapour in the fluid flow direction is neglected. For periods of no air flow, diffusion in the direction of the bed axis occurs; and for both the air flow and no air flow cases, heat transfer through the container walls is included. From the foregoing, three operating modes are possible—charging, discharging and no flow—and when charging or discharging there may be variations in the air flow rate. A repeatable random number sequence is used to determine the mode of operation at each time step during the numerical integration, and the magnitude of the random number determines the air flow rate. For this random number sequence the effects of wall losses and adsorption capacity of the adsorbent (on store performance) are studied.
[1]
Norman R. Sheridan.
Performance of the brisbane solar house
,
1972
.
[2]
G. E. Kelly,et al.
Method of testing for rating thermal storage devices based on thermal performance. Interim report
,
1975
.
[3]
D. Close,et al.
Coupled equilibrium heat and single adsorbate transfer in fluid flow through a porous medium — II Predictions for a silica-gel air-drier using characteristic charts
,
1972
.
[4]
W. R. Read,et al.
A solar Timber Kiln
,
1974
.
[5]
D. Kunii,et al.
Studies on effective thermal conductivities in packed beds
,
1957
.
[6]
D. Close,et al.
Coupled heat and mass transfer in a packed bed with the lewis relation not satisfied
,
1974
.