Tutorial Saturation Flow Rate

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What is the Saturation Flow Rate
The saturation flow rate is the maximum hourly volume that can pass through an intersection, from a given lane or group of lanes, if that lane (or lanes) were allocated constant green over the course of an hour.

$$h_{sat}=\frac{T_{i}-T_{4}}{i-4}$$

$$SLT=T_{4} - 4h_{sat}$$

$$s=\frac{3600}{h_{sat}}$$

where,

Run Simulation

 * 1) Open Swashsim (version 2019.12.6.1).
 * 2) Open the project file(download from GitHub or build network by yourself) and the network file.
 * 3) Hit the Simulation Button.
 * 4) Set a warm-up time and a simulation Duration.
 * 5) Select Link Performance Measure data, Detector Aggregate Measures Data, Detector Vehicle Actuation Data, Vehicle Headway Data and Vehicle Time Step Data for output options.
 * 6) Hit the Run Simulation button.

Verify final result

 * 1) Open the every link csv files by excel. eg.open “Link_1213-_lane_1_Detector_1_1_1” in MS Excel
 * 2) Find if there are any continuous queue lengths between 8 and 10 vehicles. eg. look at queue status column find if there are continuous queue status whose number of queuing vehicle is over 8 and under 10.
 * 3) In this queue, the actuation time of the fourth vehicle is T4. And the actuation time of the last vehicle in queue is Ti. eg. the first vehicle has a status of “slowing in queue”, you could count to the fourth vehicle and the last vehicle.
 * 4) Formula of head way and saturation flow rate are given in the preceding part of the text and these could be used to verify the final saturation flow rate. $$h_{sat}=\frac{T_{i}-T_{4}}{i-4}$$ $$s=\frac{3600}{h_{sat}}$$
 * 5) Verify to results in "flowrate.csv" eg.They are consistent with previous results(the column T in "flowrate.csv"). Also, the link id, lane id and first vehicle in "flowrate.csv" should be same as found.