LOAD FACTOR EFFECTS ON THERMALLY STRATIFIED SC! AR STORAGE TANKS

The effect of load factor on stratified tanks was experimentally investigated. The collector circuit and load circuits were simulated by a specially developed microcomputer control unit and a variety of tests encompassing domestic use conditions were carried out. It was found that a low collector flow rate of about 0.0033 L/s.m2 performs better than the value of 0.01 L/s.m2 used in most current designs. Reducing the user demand delivery temperature from 60 °C to 45 °C, and compensating for energy demand by increasing the load volume, could produce important energy savings for an average U.K. family. Drawing hot water at noon was the optimum daily usage pattern, whereas morning-peaks produced the worst results. Several control strategies were also tested with the aim of improving the overall performance. More work in this field is necessary with a floating hose inlet replacing the normal fixed inlet. Although the results were based on average U.K. weather data, the effect of randomness in climate and user demand was also investigated. It was concluded that a cooperative user implementing the recommended system operating conditions, as well as matching large loads with solar heat availability, should achieve annual savings of about 1.69 GJ (469 kWh) or more, when compared to a more conventional operating regime. Two computer models of stratification were compared and their predictions showed a fairly good agreement with the experimental results.

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

1985

Author dc:creator

• TABARRA, MOHAIJMAD

Licence

• https://dora.dmu.ac.uk/bitstreams/97aab70d-709d-4694-9aa0-f3b72b8680fa/download