page_title: Traffic flow
section_title: Newell-Daganzo Merge Models
hierarchical_section_title: Traffic flow / Newell-Daganzo Merge Models
caption_attribution_description: English: Diagram for Newell daganzo merge model
context_page_description: In mathematics and transportation engineering, traffic flow is the study of interactions between travellers and infrastructure, with the aim of understanding and developing an optimal transport network with efficient movement of traffic and minimal traffic congestion problems.
context_section_description: In the condition of traffic flows leaving two branch roadways and merging into a single flow through a single roadway, determining the flows that pass through the merging process and the state of each branch of roadways becomes an important task for traffic engineers. the Newell-Daganzo merge model is a good approach to solve these problems. This simple model is the output of the result of both Gordon Newell's description of the merging process and the Daganzo's cell transmission model. In order to apply the model to determine the flows which exiting two branch of roadways and the stat of each branch of roadways, one needs to know the capacities of the two input branches of roadways, the exiting capacity, the demands for each branch of roadways, and the number of lanes of the single roadway. The merge ratio will be calculated in order to determine the proportion of the two input flows when both of branches of roadway are operating in congested conditions.
  As can be seen in a simplified model of the process of merging, the exiting capacity of the system is defined to be μ, the capacities of the two input branches of roadways are defined as μ₁ and μ₂, and the demands for each branch of roadways are defined as q₁ᴰ and q₂ᴰ. The q₁ and q₂ are the output of the model which are the flows that pass through the merging process. The process of the model is based on the assumption that the sum of capacities of the two input branches of roadways is less than the exiting capacity of the system, μ₁+μ₂ ≤ μ.
caption: The diagram of Newell-Daganzo merge model and its variables
exif: {}