11. |
- Carlsson, Bo, et al.
(författare)
-
The Photochemical Heat Pipe
- 1978
-
Ingår i: Solar Energy. ; 21:2, s. 87-92
-
Tidskriftsartikel (refereegranskat)abstract
- The performance of a solar collector system for high temperature heat delivery based on a photochromic reaction is discussed. The system consists of a non-focusing collector and a reactor integrated into a flow system. In the collector, kept close to ambient temperature, the chemical potential of the photochromic system is increased through an endothermic photochemical reaction and is used to drive the reverse thermal reaction taking place in the reactor at a high temperature. No separation of the photoproducts is involved. Accordingly, the highest temperature at which heat can be delivered from the reactor is determined by the maximum attainable photostationary state in the collector and not, as in a conventional flat-plate collector, by heat-loss from the collector to the surroundings. Accordingly, the highest temperature at which heat can be delivered from the reactor is determined by the maximum attainable photostationary state in the collector and not, as in a conventional flat-plate collector, by heat-loss from the collector to the surroundings. The functioning of the device is exemplified by calculations for a model system utilizing the photodissociation of gaseous nitrosylchloride. The results show that it should be possible to build a system which, on a clear day, delivers about 100 W heat at temperature above 200°C for each m2 collector area. A tenfold reduction in the radiation flux density of the incident light will only slightly reduce output efficiency.
|
|
12. |
- Carlsson, Bo, et al.
(författare)
-
The Photochromic Properties of the System CuCl(s)-H2O(l) in Relation to the Composition of the Aqueous Solution
- 1979
-
Ingår i: Journal of Photochemistry. - : Elsevier BV. - 0047-2670. ; 11:6, s. 403-412
-
Tidskriftsartikel (refereegranskat)abstract
- The photochromic properties of the system CuCl(s)---H2O(l) in relation to the composition of the aqueous solution were studied using diffuse reflectance spectroscopy. The photochemical disproportionation of Cu+ into Cu2+ and Cu0 proved to be essentially independent of pH, ionic strength and the concentrations of Cu2+ and Cl− in the solution. The reverse reaction, i.e. thermal fading, takes place in two steps, one initial exponential step followed by a second step of zero order, i.e. of constant reaction rate. For both steps the reaction rate is independent of the concentration of metallic copper. The rate of the initial step is proportional to the product of the Cu2+ and Cl− concentrations of the solution. The rate of the second step is independent of the Cu2+ concentration and proportional to the Cl− concentration. The results are consistent with the following mechanism for the bleaching reaction: (I) diffusion of Cu2+---Cl− complexes to reaction sites on the surface; (II) fast chemical reaction between Cu2+---Cl− and Cu0 at the reaction sites yielding CuCl; (III) desorption of the product CuCl by complex formation with Cl− ions.
|
|
13. |
- Stymne, Hans, et al.
(författare)
-
Chemical Storage of Energy
- 1978
-
Ingår i: "Solar Energy North Sun 50"; SEAS International Conference. - Stockholm.
-
Konferensbidrag (refereegranskat)
|
|
14. |
- Wettermark, Gunnar, et al.
(författare)
-
Storage of Heat - A Survey of Efforts and Possibilities
- 1979
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Various methods are described for storing heat. Topic areas discussed include the following: the role of heat storage in different energy systems; heat storage with passive and active solar heat systems; sensible heat; latent heat - phase change; thermochemical reactions; the American program for storage of heat.
|
|
15. |
|
|