1. Why the node show fire flow (available) is zero?
- Calculation type: Fire Flow
- If a node demand input wrong (e.g. 2400 gpm, insead of 24gpm), the adjacent nodes available fire flow will be very low, since that node absorb a lot available flow. So, please check the unusual water demands.
2. How to compare model result to the hydrant flow test result?
- Hydrant flow test result will only consider a single point flow capacity at 20psi. A hydraulic model will consider a whole water distribution system (all the points within a pressure zone) to be above 20psi.
- The field measured static pressure at a residual hydrant only indicates a normal operating pressure. If we calculate a huge demand of fire flow from a water source (e.g. tank, pumping station) to a job site, the operating pressures along the pipe route will drop, since the friction losses will increase dramatically. So, the field test static pressure is incomparable to a modeled operating pressure.
- If you want to know the operating pressures along a pipe route, you may simulate the fire flow demand at one junction with a static flow analysis.
3. How to simulate the 2hr fire flow?Technorati Tags: