Parameters #
Additional parameters have been added with regard to the force main design, with explanations in each picture below. Kindly take note that changes in parameters will not affect the design for normal sewers
Material Pipe Type #
Parameters poisson ratio and elasticity have been added, which will be used to calculate the force main resistance to surge pressure
Design Diameter #
Design pressure (Normal) shows force main resistance to normal pressure, whereas design pressure (burst) shows force main resistance to surge pressure; Pipe wall thickness shows sewer thickness (outer diameter minus inner diameter)
Design Sewage #
Parameters circled are used in calculation of surge pressure for force main
Design Force Main #
Parameters circled below will affect the following:-
- Storage well: Max. Retention Time (Storage Well), Min. Pumping Cycle, Max. Pumping Cycle
- Force main: Min. remaining head at end, Min. Velocity, Max. Velocity, Max. Retention Time (Force Main), Min upwards increment from force main
Note: ’Receiving Pipe Pressure Calculation’ parameter will help to calculate if the downstream pipe is able to withstand remaining pipe pressure at force main end if changed to ‘Yes’
Pipe & Storage Well Input #
Pump flow requires input in force main UI to run correctly, which can be accessed via clicking on the button circled in red in the picture below
(this is only applicable when the flow type has been switched to pumped flow)
Parameters circled below will affect the following:-
- Well Area (Plan View), Operating Depth, Pump flow: Pumping cycle, Retention Time (Storage Well & Force Main)
- Pressure at downstream end of force main: Pump Head, Minor Head Loss Coefficient, Force Main Support Condition, Pressure Reducing Valve Limit
- Invert level of force main upstream end: Emergency Depth, Operating Depth, Pump Storage Depth
Calculating Results and Export #
Result tabs ‘Excel Report’ and ‘Textual Report’ will be updated with force main-related results. For exporting results, kindly refer to section 6
Excel report #
Excel report has been updated with storage well and pressure calculation results
Textual report #
For sewers identified with pumped flow, calculations will be modified to show calculations for force main and storage well designs.
Nodes and Sewers Element Reordering #
Starting from MiTS 2.4.30 version, users are now allowed to reorder the numbering for nodes / lines (available for drainage & sewer module).
Concepts applied:
- The numbering will always start at the upstream and then proceed gradually to downstream,
- The numbering will strive to be consecutive when moving from one pipes/drains to another,
- The upper stream will always have smaller running compared to the downwards stream.
Therefore, it is expected that the last node / drains will always be the biggest number.
For example;
Users will require to analyse and go to input tab
As the image above, to reorder the node number click ‘Renumber Node’ OR to reorder the sewerage number click ‘Renumber Edge’
*Please refer image 3 and image 4
