Calculation flow rates (Drinking water wizard options)
In the Calculation flow rates area, select whether the calculation flow rate from the reference values of DIN 1988-300 or from the stored manufacturer specifications is used for the design.
- Activate the Reference values DIN 1988-300 radio button if you want to use the reference values from DIN 1988-300 for the calculation.
- Activate the Manufacturer specifications radio button if the calculation flow rate is to be calculated according to the manufacturer's specifications. Important:
If the manufacturer's specification of the calculation flow rate is greater than the stored reference value from DIN 1988-300, the calculation flow rates are calculated according to the manufacturer's specification regardless of the activated option.
If the manufacturer's specification of the calculation flow rate is less than the stored reference value from DIN 1988-300, the reference values according to DIN 1988-300 are used for the calculation if the "DIN 1988-300 reference values" option is activated.
If the manufacturer's specification of the calculation flow rate is less than the stored reference value from DIN 1988-300, the calculation flow rates are calculated according to the manufacturer's specifications if the "Manufacturer's specifications" option is activated.
- Select the discharge times from the drop-down menu, taking into account the volume flow rate Vr, the volume flow rate at static pressure or the volume flow rate at dynamic pressure. Note:
Volume flow rate Vr: This setting is intended to allow quick comparison with rough estimates. However, this is not recommended when calculating discharge times, as the valve characteristic curve is not taken into account here and, where applicable, the pressure at the calculation flow rate VR may be below the static pressure.
Volume flow at static pressure: This setting is set as the default, as during an on-site test of the discharge times, the water bodies are at rest in order to obtain reproducible discharge times. When setting the static pressure, the geodetic height is taken into account and a check is carried out to ensure that all section segments were in a state of stagnation. It can be assumed that the majority of the network will be calculated using the highest withdrawal flow rate.
Volume flow at flow pressure: Taking the flow pressure into account, the minimum withdrawal volume flow is considered; however, this is only the case for short periods, as the flow pressure is established only when account is taken of the simultaneities within the network. Furthermore, operation is assumed here in which stagnation of the section is not guaranteed.Attention:The set pressure affects the withdrawal flow rate in the calculation and in the water withdrawal simulation.