21 research outputs found
Non-residential water demand model validated with extensive measurements and surveys
Existing Dutch guidelines for the design of the drinking water and hot water
system of non-residential buildings are based on outdated assumptions on
peak water demand or on unfounded assumptions on hot water demand. They
generally overestimate peak demand values required for the design of an
efficient and reliable water system. Recently, a procedure was developed
based on the end-use model SIMDEUM to derive design-demand-equations for
peak demand values of both cold and hot water during various time steps for
several types and sizes of non-residential buildings, viz. offices, hotels
and nursing homes. In this paper, the design-demand-equations are validated
with measurements of cold and hot water patterns on a per second base and
with surveys. The good correlation between the simulated water demand
patterns and the measured patterns indicates that the basis of the
design-demand-equations, the SIMDEUM simulated standardised buildings, is
solid. Surveys were held to investigate whether the construction of the
standardised buildings based on the dominant variable corresponds with
practice. Surveys show that it is difficult to find relationships to equip
the standardised buildings with users and appliances. However, the
validation proves that with a proper estimation of the number of users and
appliances in only the dominant functional room of the standardised
buildings, SIMDEUM renders a realistic cold and hot water diurnal demand
pattern. Furthermore, the new design-demand-equations based on these
standardised buildings give a better prediction of the measured peak values
for cold water flow than the existing guidelines. Moreover, the new
design-demand-equations can predict hot water use well. In this paper it is
illustrated that the new design-demand-equations lead to reliable and
improved designs of building installations and water heater capacity,
resulting in more hygienic and economical installations