In this paper, an improved ant colony optimization (ICMPACO) algorithm based on the multi-population strategy, co-evolution mechanism, pheromone updating strategy, and pheromone diffusion mechanism is proposed to balance the convergence speed and solution diversity, and improve the optimization performance in solving the large-scale optimization problem. In the proposed ICMPACO algorithm, the optimization problem is divided into several sub-problems and the ants in the population are divided into elite ants and common ants in order to improve the convergence rate, and avoid to fall into the local optimum value. The pheromone updating strategy is used to improve optimization ability. The pheromone diffusion mechanism is used to make the pheromone released by ants at a certain point, which gradually affects a certain range of adjacent regions. The co-evolution mechanism is used to interchange information among different sub-populations in order to implement information sharing. In order to verify the optimization performance of the ICMPACO algorithm, the traveling salesmen problem (TSP) and the actual gate assignment problem are selected here. The experiment results show that the proposed ICMPACO algorithm can effectively obtain the best optimization value in solving TSP and effectively solve the gate assignment problem, obtain better assignment result, and it takes on better optimization ability and stability.

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An Improved Ant Colony Optimization Algorithm Based on Hybrid Strategies for Scheduling Problem

Heat transfer behavior of nanoparticle enhanced PCM solidification through an enclosure with V shaped fins

Heat transfer simulation of heat storage unit with nanoparticles and fins through a heat exchanger

Heat transfer and turbulent simulation of nanomaterial due to compound turbulator including irreversibility analysis

Heat transfer of nanoparticles employing innovative turbulator considering entropy generation

Huge amount of efforts were done on saturated steam flow in wellbores with relatively little work on superheated multi-component thermal fluid (SMTF) flow in wellbores. In this paper, based on the continuity, energy and momentum balance equations, a flow model in the vertical wellbores is proposed. Then, coupled with the real gas model and transient heat flow model in formation, a comprehensive model is established for estimating thermophysical properties of SMTF in wellbores. Results show that (a) the effect of mass content of non-condensing gases on temperature profiles is negligible. The enthalpy of SMTF decreases rapidly with increasing of mass content of non-condensing gases. (b) When the injection rate is small, heat loss is the main factor on temperature drop, while when the injection rate is large enough, pressure drop becomes the dominant factor on temperature drop. (c) The two components of non-condensing gases and superheated steam in SMTF have a relatively independent mechanism of enhanced oil recovery, which should be selected based on the unique characteristics of each reservoir.

/pdf/effect-analysis-of-non-condensable-gases-on-superheated-2kuuqy68et.pdf

Effect analysis of non-condensable gases on superheated steam flow in vertical single-tubing steam injection pipes based on the real gas equation of state and the transient heat transfer model in formation

Fengrui Sun

Papers

Effect analysis of non-condensable gases on superheated steam flow in vertical single-tubing steam injection pipes based on the real gas equation of state and the transient heat transfer model in formation

Analysis of superheated steam performance in offshore concentric dual-tubing wells

Simulation of real gas mixture transport through aqueous nanopores during the depressurization process considering stress sensitivity

Effect of gaseous CO2 on superheated steam flow in wells

Assessment of hydrate blockage risk in long-distance natural gas transmission pipelines