Multi-objective optimization on structural parameters of torsional flow heat exchanger

The heat conduction and fluid friction are two main detrimental irreversibilities in heat exchanger. According to the entransy dissipation theory, the entransy dissipation can be employed to quantify these two irreversibilities. In the present work, the optimization of heat exchanger design is investigated by applying the entransy dissipation theory and genetic algorithm. Firstly, by taking the total dimensionless entransy dissipation caused by heat conduction and fluid friction as objective function, a single-objective optimization approach to heat exchanger design is developed. However, it is found that the role played by the fluid friction is not fully taken into account in this approach when the working fluid of heat exchanger is liquid. In order to circumvent this problem, the non-dimensional entransy dissipations associated with heat conduction and fluid friction are taken as two separate objective functions and a multi-objective optimization approach to heat exchanger design is established. In comparison with the single-objective optimization approach, the multi-objective optimization approach demonstrates more advantages and flexibilities for heat exchanger design.

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Multi-Objective Optimization of Structural Parameters for Rotary Flow Jetting Tool Based on Orthogonal Experiment

International Journal of Design & Nature and Ecodynamics ◽

10.18280/ijdne.150612 ◽

2020 ◽

Vol 15 (6) ◽

pp. 865-871

Author(s):

Leilei Liu ◽

Jie Liu ◽

Zuqing He ◽

Huanle Liu ◽

Chao Zhou ◽

...

Keyword(s):

Orthogonal Experiment ◽

Structural Parameters ◽

Fluid Simulation ◽

Multi Objective Optimization ◽

Pipe Length ◽

Multi Objective ◽

Gas Recovery ◽

Orthogonal Experiments ◽

Wing Width ◽

Principle Of Similarity

There is no precedent for the application of rotary flow jetting tool in the drainage gas recovery under gas wells. Based on the motion principles of jet flow and vortex flow, this paper designs a downhole rotary flow jetting tool, and verifies the feasibility of the tool through fluid simulation. Next, an indoor experiment device was established for drainage gas recovery with rotary flow jetting tool by the principle of similarity, and the structural parameters of the tool were subject to multi-objective optimization through orthogonal experiments. The optimized tool can achieve ideal rotary flow height and discharge volume. The results show that the proposed rotary flow jetting tool can effectively separate gas from liquid, and produce a rotary flow. The optimal structural parameters were determined as follows: the pitch diameter of spiral body is 45mm, the throat pipe length is 247mm, the spiral angle is 55°-60°, the spiral wing width is 4-6mm, and the nozzle diameter is 15-25mm. In addition, the number of side holes of the throat pipe has little effect on the jetting effect.

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Multi-objective Optimization of Compliant Parallel Platform for Desired Stiffness and Workspace

10.21203/rs.3.rs-834393/v1 ◽

2021 ◽

Author(s):

Hongwei Xu ◽

Haibo Zhou ◽

Zhiqiang Li ◽

Xia Ju

Keyword(s):

Numerical Model ◽

Optimization Problem ◽

Structural Parameters ◽

Optimization Method ◽

Multi Objective Optimization ◽

Element Analysis ◽

Multi Objective ◽

Performance Indexes ◽

Parallel Platform ◽

The Relationship

Abstract Stiffness and workspace are crucial performance indexes of a precision mechanism. In this paper, an optimization method is presented, for a compliant parallel platform to achieve desired stiffness and workspace. First, a numerical model is proposed to reveal the relationship between structural parameters, desired stiffness and workspace of the compliant parallel platform. Then, the influence of the various parameters on stiffness and workspace of the platform is analyzed. Based on Gaussian distribution, the multi-objective optimization problem is transformed into a single-objective one, in order to guarantee convergence precision. Furthermore, particle swarm optimization is used to optimize the structural parameters of the platform, which significantly improve its stiffness and workspace. Last, the effectiveness of the proposed numerical model is verified by finite element analysis and experiment.

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