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4.4.4 Store capacities water
Storage capacities are related to fluidized facade area and for most localities 100 litres/m2 should be suitable. The capacity as a proportion of the total volume of the building is surprizingly small and reduces as the building size increases.
Example:-
(a) 30m x 30m x 10 floors of 3 m ceiling ht :- 1.2% of total volume, 13% of basement volume.
(b) 60m x 60m x 10 floors of 3 m ceiling ht :- 0.6% of total volume, 6.7% of basement volume.
Computer simulations for a medium size fluid glazed building (a) above indicate that a comfortable interior temperature of 21 - 22 deg. C may be maintained summer and winter without any other cooling or heating, except for very extreme conditions.
5 The McKee System
The McKee Fluidized Glazing & Cladding system for the environmental control of buildings comprises three subsystems :-
1 Facades The fluidized glazing or cladding system with distribution control connecting to the other systems and to ambient.
2 Stores The energy storage system, which may include both cool and warm storage.
3 Heat Exchangers* The internal air to water heat exchange system, thermally connecting the storage and/or facades to the building interior.
The basics of this system are shown in Figure 3.
* The physical size of heat exchangers :-
Calculations and actual tests on heat exchangers with low air flow around 1 m/sec. and with low temperature differences (< 1 to < 2 deg. C) show that the physical size of the heat exchangers required for the system are quite small and easily implemented in the interior of the building.
The test data, calculations and results are available upon request. Ask for file :-
FGHXR1 - The Physical size of the room heat exchanger.
Storage in water or concrete or air
The heat capacity of;
Water is 4.2 Joules per gm per deg. C, = 1.163 kWh /m3 deg.C
Concrete 0.8 = 0.222 ,, ,,
Air 1.0 = 0.277 ,, ,,
For the same weight water can store 5.2 times as much energy as concrete. And in terms of volume :-
One cubic meter of water can store 3.3 times as much as one cubic meter of concrete (without allowing for air holes to extract the energy)
If allowance is made for the required holes or air passages then one needs double the volume i.e. about 7 cubic meters of concrete for one cubic meter of water.
costs:- concrete costs 200 - 500 times that of water !
A fluidized building may be less massive than other buildings and still exhibit slow temperature changes.
To transfer the same amount of energy using air requires 3,467 times the volumetric flow as with water !
Trains and motor coaches and some forms of water craft.
The fluidized system may be applied to trains, coaches and some boats with very advantageous results; as direct solar radiation cannot impinge on both sides at one time. And solar photo - voltaic cells may be used to power the pumps and valves. Pleasure boats could have cool interiors without noisy cooling equipment running.
Some articles have wrongly referred to Fluidized Glazing as "Wet Windows"
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