An innovative design for left turn bicycles at continuous flow intersections

In the light that heavy left-turn vehicles and oncoming vehicles conflict at conventional intersection(CI), leading to discontinuity and low efficiency of traffic flow, this paper presents a new continuous flow intersection(CFI) for urban roads. The geometry physical model and design principles of the CFI are illustrated and the CFI is designed from following three aspects: traffic space, traffic organization and traffic control. Experiments taking the CI and corresponding the CFI as the reseach objects are carried on, and performance of the proposed the CFI is validated via VISSIM. Extensive simulation results under five traffic conditions have demonstrated the potential of the proposed the CFI for improvement of traffic efficiency, and the applicability of the CFI in China is discussed considering the characteristics of domestic urban intersections and it indicates that the CFI could be applied to domestic suburb roads.

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The Effect of Modifying Double Continuous Flow Intersections Layout Geometric Features on their Operation

The Open Transportation Journal ◽

10.2174/1874447802115010001 ◽

2021 ◽

Vol 15 (1) ◽

pp. 1-10

Author(s):

Ibrahim Khliefat ◽

Ahmad Deeb ◽

Mohammad Mubarak ◽

Mohammad Naser

Keyword(s):

Urban Areas ◽

Continuous Flow ◽

Simulation Models ◽

Intersection Angle ◽

Left Turn ◽

Limited Space ◽

Operational Characteristics ◽

Layout Geometry ◽

The Cross ◽

And Performance

Introduction: Continuous flow interventions were first introduced as an alternative to improve traffic operations in the intersections with severe congestion caused by heavy left-turn movements. Objective: This study quantified the effect of modifying the intersection angles of Double Continuous Flow Intersections (DCFI) on their operational characteristics. Mainly, the effects of changing the intersection angle between the different approaches of the main intersection and the angle of the minor cross-over intersections were investigated. Methods: VISSIM software simulation models were used for modifying several design features related to the DCFI and the operational performance was compared between the different simulation scenarios. Results and Discussion: Changes to the cross-over intersection angle increase the safety levels by providing better channelization of traffic movements on the minor intersections of the DCFI and reduce the intersection footprint to be used at high-density urban locations. Increasing the cross-over intersection angle and changing the layout geometry have adverse effects on the capacity of the conventional DCFI. This is mainly because of the added curvature in the intersection approaches which reduces the vehicle speeds, therefore reducing the overall capacity of the modified intersection when compared to the conventional DCFI. However, the total footprint for the intersection is reduced for the modified layout geometry, which improves the capacity of the DCFI. Conclusion: The study has explored the effects of modifying the DCFI intersection angles to fit the limited space in major urban areas on the capacity and performance of the intersection. It showed that DCFI designs could be applied in areas with limited space availability and skewed intersection angles.

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Sustainable Design of Diverging Diamond Interchange: Development of Warrants for Improving Operational Performance

Sustainability ◽

10.3390/su12145840 ◽

2020 ◽

Vol 12 (14) ◽

pp. 5840

Author(s):

Meshal Almoshaogeh ◽

Hatem Abou-Senna ◽

Essam Radwan ◽

Husnain Haider

Keyword(s):

Performance Comparison ◽

Simulation Software ◽

Average Delay ◽

Innovative Design ◽

Left Turn ◽

Conventional Design ◽

Safety Risks ◽

Traffic Volumes ◽

Diamond Interchanges ◽

Measures Of Effectiveness

Conventional diamond interchanges are facing ever-growing challenges related to traffic operations and safety risks due to increasing traffic volumes and worsening congestions. The agencies are well aware of the high socioeconomic (e.g., user delay cost, fuel cost, and high accident rates) and environmental losses (traffic emissions due to vehicles queuing) associated with the conventional interchange design. This paper provides insight into the different factors that affect the sustainability performance (operational and safety) of a conventional interchange through its redesign into the Diverging Diamond Interchange (DDI) with the increased left-turn demand. It also assesses the need to redesign an interchange to improve the efficiency. Two interchanges that have DDI designs were selected for investigations, and the required data were collected from the relevant agency. The average delay and the capacity were used as the Measures of Effectiveness (MOEs) for data analysis. Numerous factors, that affected these MOEs, were used to design an experiment. This experiment included different levels of volumes, geometric designs, and signal plans. The micro-simulation software (VISSIM 8.0) was employed to calibrate and validate the existing conditions through several steps, including signal optimization and driving behavior parameter optimization. The analysis of the results detected the key thresholds of switching from the conventional design to the innovative design under 90 different scenarios. Finally, the sustainability evaluation of DDI and Conventional Design Interchange was conducted based on their operation and safety performance comparison. The results and findings of this research will act as a guideline for decision-makers regarding when they should consider switching from the conventional interchange design to an innovative design.

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INNOVATIVE DESIGN OF A CONTINUOUS FLOW PHOTOELECTROCHEMICAL REACTOR: HYDRAULIC DESIGN, CFD SIMULATION AND PROTOTYPING

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2021.105917 ◽

2021 ◽

pp. 105917

Author(s):

Gustavo Corte Tedesco ◽

Peterson Bueno Moraes

Keyword(s):

Continuous Flow ◽

Cfd Simulation ◽

Innovative Design ◽

Hydraulic Design

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Catalyst- and oxidant-free electrochemical para-selective hydroxylation of N-arylamides in batch and continuous-flow

Green Chemistry ◽

10.1039/d0gc02294b ◽

2020 ◽

Vol 22 (19) ◽

pp. 6437-6443

Author(s):

Cheng-Kou Liu ◽

Meng-Yi Chen ◽

Xin-Xin Lin ◽

Zheng Fang ◽

Kai Guo

Keyword(s):

Ammonium Salt ◽

Quaternary Ammonium ◽

Continuous Flow ◽

Quaternary Ammonium Salt ◽

Selective Hydroxylation

A catalyst-, oxidant-, acidic solvent- and quaternary ammonium salt-free electrochemical para-selective hydroxylation of N-arylamides at rt in batch and continuous-flow was developed.

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