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A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
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Optimization Design and Performance Evaluation of R1234yf Ejectors for Ejector-Based Refrigeration Systems.

Meihong Yu1, Chen Wang1, Lei Wang1

  • 1School of Control Science and Engineering, Shandong University, Jinan 250061, China.

Entropy (Basel, Switzerland)
|November 11, 2022
PubMed
Summary

This study optimizes R1234yf ejector refrigeration systems (ERS) using a gas dynamic method. Geometric parameter optimization significantly improved ejector performance by 17%, addressing a key bottleneck for eco-friendly cooling.

Keywords:
R1234yf ejectorejector designejector refrigeration systementrainment ratioperformance improvement

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Area of Science:

  • Thermodynamics and Refrigeration Engineering
  • Fluid Dynamics
  • Sustainable Energy Systems

Background:

  • Growing energy and environmental concerns necessitate efficient and eco-friendly refrigeration solutions.
  • R1234yf ejector refrigeration systems (ERS) offer advantages like simplicity and low environmental impact.
  • Suboptimal ejector performance currently limits the widespread application of ERS.

Purpose of the Study:

  • To propose a gas dynamic design method for R1234yf ejectors.
  • To optimize key geometric parameters, specifically area ratio (AR) and nozzle exit position (NXP), for enhanced ejector performance.
  • To improve the overall efficiency and applicability of R1234yf ERS.

Main Methods:

  • Development of a gas dynamic design approach for R1234yf ejectors.
  • Utilizing control variable optimization algorithms to adjust geometric parameters (AR and NXP).
  • Employing a validated simulation model to analyze ejector performance and fluid dynamics.

Main Results:

  • The entrainment ratio initially increases and subsequently decreases with rising AR and NXP, respectively.
  • Area ratio significantly impacts shock wave location within the mixing chamber.
  • Nozzle exit position directly influences the expansion state of the motive fluid.
  • Optimized parameters led to a 17% increase in ejector performance compared to the baseline.

Conclusions:

  • The proposed gas dynamic design method and parameter optimization effectively enhance R1234yf ejector performance.
  • Optimized AR and NXP are crucial for maximizing entrainment ratio and system efficiency.
  • This research provides valuable guidance for designing R1234yf ejectors, promoting sustainable ERS development.