# CFD Simulation and Experimental Study of Working Process of Screw Refrigeration Compressor with R134a

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## Abstract

**:**

## 1. Introduction

## 2. Geometric Model Building and Meshing

## 3. Simulation Settings

#### 3.1. Governing Equation

#### 3.2. Boundary Condition Settings

#### 3.3. Grid Independence Verification

## 4. Experiment

^{3}·min

^{−1}.

## 5. Results and Discussion

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## Nomenclature

${S}_{m}$ | Source term |

$p$ | Pressure on the microelement |

${\mathsf{\tau}}_{xy}$ | Component of the viscous stress τ |

F | Volume force on the microelement |

K | Heat transfer coefficient |

T | Temperature |

${c}_{p}$ | Specific heat capacity |

${S}_{T}$ | Internal heat source and the viscous dissipation term |

${G}_{k}$ | Kinetic energy of turbulence |

${\Gamma}_{k}$ | Effective diffusion terms of $k$ |

${\Gamma}_{\omega}$ | Effective diffusion terms of $\omega $ |

${Y}_{k}$ | Divergent terms for $k$ |

${Y}_{\omega}$ | Divergent terms for $\omega $ |

${D}_{\omega}$ | Orthogonal divergence |

${S}_{k}\&{S}_{\omega}$ | User-defined item |

## References

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**Figure 2.**Meshing of different fluid domains. (

**a**) Suction port fluid domain grid. (

**b**) Discharge port fluid domain grid, (

**c**) Two-dimensional mesh of volumetric element.

**Figure 4.**Mesh independence verification. (

**a**) Mesh numbers in different cases. (

**b**) Volume flow in different cases. (

**c**) P-θ diagram in different cases. (

**d**) Power in different cases.

**Figure 5.**Experimental device. (

**a**) Pressure sensor in the female rotor. (

**b**) Experimental test compressor.

**Figure 8.**The pressure distribution of the intermeshing clearance of the rotors at different angles.

**Figure 9.**The temperature distribution of the surface of the male and female rotors: (

**a**) male rotor; (

**b**) female rotor.

**Figure 11.**The leakage velocity vector: (

**a**) the leakage velocity vector of the intermeshing clearance; (

**b**) the leakage velocity vector of the radial clearance.

**Figure 13.**The P-θ diagram of the screw refrigeration compressor under partial load (75%) conditions.

**Figure 15.**Comparison of the compressor performance under two working conditions. (

**a**) Input power; (

**b**) Volumetric efficiency; (

**c**) Isentropic efficiency.

Parameters | Measured Value |
---|---|

Inlet pressure | 0.285 MPa |

Inlet temperature | 274 K |

Discharge pressure | 1.515 MPa |

Discharge temperature | 360.4 K |

Volume flow | 3.254 m^{3}·min^{−1} |

Case | Circumferential Nodes | Radial Nodes | Axial Nodes | Volume Flow/m^{3}·min^{−1} | Number of Meshes |
---|---|---|---|---|---|

Case 1 | 360 | 30 | 125 | 2.633 | 3,848,194 |

Case 2 | 720 | 20 | 125 | 2.807 | 4,536,394 |

Case 3 | 720 | 30 | 125 | 2.837 | 6,477,694 |

Case 4 | 720 | 20 | 200 | 3.248 | 6,693,394 |

Case 5 | 720 | 20 | 250 | 3.251 | 8,203,294 |

Parameter | Male Rotor | Female Rotor |
---|---|---|

Number of teeth | 5 | 6 |

Diameter of rotor D/mm | 138.507 | 109.76 |

Length of rotor L/mm | 152 | 152 |

Wrap angle of male rotor | 300° | 250° |

Screw lead of the male rotor T/mm | 181.761 | 218.113 |

Method | 75% Load | 100% Load | ||||
---|---|---|---|---|---|---|

Input Power | Volumetric Efficiency/% | Isentropic Efficiency/% | Input Power | Volumetric Efficiency/% | Isentropic Efficiency/% | |

Measured | 26.986 | 52.583 | 61.281 | 39.9 | 85.699 | 70.356 |

CFD | 26.325 | 51.848 | 59.701 | 39.643 | 85.541 | 69.686 |

Error% | 2.449 | 1.398 | 2.578 | 0.645 | 0.184 | 0.952 |

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## Share and Cite

**MDPI and ACS Style**

Wu, H.; Huang, H.; Zhang, B.; Xiong, B.; Lin, K. CFD Simulation and Experimental Study of Working Process of Screw Refrigeration Compressor with R134a. *Energies* **2019**, *12*, 2054.
https://doi.org/10.3390/en12112054

**AMA Style**

Wu H, Huang H, Zhang B, Xiong B, Lin K. CFD Simulation and Experimental Study of Working Process of Screw Refrigeration Compressor with R134a. *Energies*. 2019; 12(11):2054.
https://doi.org/10.3390/en12112054

**Chicago/Turabian Style**

Wu, Huagen, Hao Huang, Beiyu Zhang, Baoshun Xiong, and Kanlong Lin. 2019. "CFD Simulation and Experimental Study of Working Process of Screw Refrigeration Compressor with R134a" *Energies* 12, no. 11: 2054.
https://doi.org/10.3390/en12112054