Modelling of Domestic Hot Water Tank Size for Apartment Buildings

conference paper

English

The properly designed hot water tank should provide water supply at prescribed parameters during operation time within the apartment building at the lowest investment and operation costs. Its size is based on the graph sketch of two timely dependent functions. The first one describes the energy supply into the tank; the second describes the energy (hot water) output from the tank. Especially the second function depends on factors with random character. The paper deals with the analysis of both functions and evaluates their influence on the tank size. Starting basis for solving these problems are real data series picked up from measurements of hot water consumption within apartment buildings. The paper is focused on central domestic hot water supply systems with small outputs of heat resources which supply the number of flats between 32 to 60. There is created the probability model of hot water demand and following application of this model leads towards the determination of the possible usable tank size. Therefore it can be stated that: (a) in the case of continuous heat supply during the whole period (24 hours) the decisive factor for the tank design is the Sunday curve of hot water demand, heat losses do not influence the tank sizing but they have to be compensated by higher output of heat source, (b) in the case of continual heat supply except night hours (17 hours) during which the heat supply is interrupted there is decisive the characteristic curve for working days, currently there is a distinct increase of tank size which rises with heat losses too and which is most remarkable during working days.

Apartment buildings; hot water consumption; analysis; probability model; usable tank capacity

BÁRTA, L.

2004

16. 9. 2004

CSTB

Paříž

1/3

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