# Study on the Heat Reduction Effect of Biomimetic Unidirectional Transporting Channels Inspired by Nepenthes alata

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

#### 2.1. Materials and Elliptical Vibration Machining (EVM)

#### 2.2. Experimental Design and Set Up

## 3. Results

#### 3.1. Temperature Variation of the Test Sample

#### 3.2. Temperature Reduction Variation along with the Changing Flow Rate

## 4. Conclusions

- With the increasing flow rate, the relative coefficient of BIMC compared with STMC also increases in general. The temperature reduction of STMC is better than that of BIMC at a lower flow rate and the critical points when the heat transfer performance of BIMC exceeds STMC.
- The existence of a critical point is associated with both the heating temperature and transporting distance of the channels.
- The high heating temperature can have better heat transfer performance for BIMC. The temperature reduction can be increased by 84 percent with the flow rate of 600 μL/min at the heating temperature of 150 °C.

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 4.**(

**a**) The model of the test sample and the container; (

**b**) The model shows the tested holes of the intermediate and end section. (

**c**) The picture of the test sample and the container with thermocouples.

**Figure 5.**(

**a**) The temperature variation with liquid flow of 200 μL/min; (

**b**) The temperature variation with liquid flow of 600 μL/min.

**Figure 6.**(

**a**) The temperature reduction along with the changing flow rate at the intermediate section; (

**b**) The temperature reduction along with the changing flow rate at the end section.

**Figure 7.**(

**a**) Temperature reduction at the intermediate section at the heating temperature of 90 °C; (

**b**) Temperature reduction at the end section at the heating temperature of 90 °C; (

**c**) Temperature reduction at the intermediate section at the heating temperature of 120 °C; (

**d**) Temperature reduction at the end section of the heating temperature of 120 °C.

**Figure 8.**(

**a**) T RC at the heating temperature of 90 °C; (

**b**) RC at the heating temperature of 120 °C; (

**c**) RC at the heating temperature of 150 °C.

Measuring Sections | Temperature Measurement Items/°C | Liquid Flow/μL/min | ||||
---|---|---|---|---|---|---|

200 | 400 | 600 | 800 | 1000 | ||

Intermediate section of BIMC | ${T}_{\mathrm{max}}$ | 136.4 | 136.3 | 131.8 | 133.8 | 132.8 |

${T}_{\mathrm{min}}$ | 116.5 | 115.5 | 111.5 | 108.3 | 111.8 | |

$\Delta T$ | 19.9 | 20.8 | 20.3 | 25.5 | 21 | |

End section of BIMC | ${T}_{\mathrm{max}}$ | 135 | 134.3 | 133.2 | 134.3 | 133.6 |

${T}_{\mathrm{min}}$ | 122.6 | 109 | 122.7 | 126.7 | 124.3 | |

$\Delta T$ | 12.4 | 25.3 | 10.5 | 7.6 | 9.3 | |

Intermediate 0 of STMC | ${T}_{\mathrm{max}}$ | 135 | 134.9 | 132.5 | 131.3 | 134.9 |

${T}_{\mathrm{min}}$ | 113.3 | 116.5 | 119.7 | 115.3 | 117.4 | |

$\Delta T$ | 21.7 | 18.4 | 12.8 | 16 | 17.5 | |

End section of STMC | ${T}_{\mathrm{max}}$ | 137.8 | 137.4 | 136 | 134.9 | 135.4 |

${T}_{\mathrm{min}}$ | 118.5 | 128.7 | 130.3 | 129.5 | 126.9 | |

$\Delta T$ | 19.3 | 8.7 | 5.7 | 5.4 | 8.5 |

Measuring Sections | Temperature Measurement Items/°C | Liquid Flow/μL/min | |||||
---|---|---|---|---|---|---|---|

50 | 100 | 150 | 200 | 250 | 300 | ||

Intermediate section of BIMC | ${T}_{\mathrm{max}}$ | 79.4 | 79.6 | 78.4 | 78.3 | 78.3 | 79.4 |

${T}_{\mathrm{min}}$ | 78.5 | 70.3 | 67.6 | 66.9 | 67.1 | 67.1 | |

$\Delta T$ | 0.9 | 9.3 | 10.8 | 11.4 | 11.2 | 12.3 | |

End section of BIMC | ${T}_{\mathrm{max}}$ | 79.4 | 79.2 | 78.9 | 78.6 | 78.7 | 79.3 |

${T}_{\mathrm{min}}$ | 78.3 | 76 | 72.6 | 70.5 | 69.8 | 69.2 | |

$\Delta T$ | 1.1 | 3.2 | 6.3 | 8.1 | 8.9 | 10.1 | |

Intermediate section of STMC | ${T}_{\mathrm{max}}$ | 80.1 | 79.9 | 78.5 | 78.5 | 78.5 | 79.3 |

${T}_{\mathrm{min}}$ | 66.1 | 70.4 | 69.1 | 67.6 | 67.4 | 67.8 | |

$\Delta T$ | 14 | 9.5 | 9.4 | 10.9 | 11.1 | 11.5 | |

End section of STMC | ${T}_{\mathrm{max}}$ | 78.3 | 78.3 | 76.8 | 76.6 | 76.9 | 77.3 |

${T}_{\mathrm{min}}$ | 76.4 | 71.7 | 68.3 | 67.3 | 67.1 | 65.8 | |

$\Delta T$ | 1.9 | 6.6 | 8.5 | 9.3 | 9.8 | 11.5 |

Measuring Sections | Temperature Measurement Items/°C | Liquid Flow/μL/min | ||||
---|---|---|---|---|---|---|

100 | 150 | 200 | 250 | 300 | ||

Intermediate section of BIMC | ${T}_{\mathrm{max}}$ | 104.5 | 104.3 | 104.5 | 104.4 | 104.6 |

${T}_{\mathrm{min}}$ | 99.8 | 91.2 | 89.2 | 88.5 | 88.9 | |

$\Delta T$ | 4.7 | 13.1 | 15.3 | 15.9 | 15.7 | |

End section of BIMC | ${T}_{\mathrm{max}}$ | 104.1 | 103.8 | 104.2 | 104.3 | 104.2 |

${T}_{\mathrm{min}}$ | 102.3 | 100.7 | 93 | 94.3 | 93.4 | |

$\Delta T$ | 1.8 | 3.1 | 11.2 | 10 | 10.8 | |

Intermediate section of STMC | ${T}_{\mathrm{max}}$ | 104.1 | 104.5 | 104 | 104.8 | 104.5 |

${T}_{\mathrm{min}}$ | 102.3 | 90.5 | 90.8 | 89.8 | 90.1 | |

$\Delta T$ | 1.8 | 14 | 13.2 | 15 | 14.4 | |

End section of STMC | ${T}_{\mathrm{max}}$ | 104.5 | 104.7 | 105 | 102.2 | 101.6 |

${T}_{\mathrm{min}}$ | 97.2 | 92.5 | 90.8 | 90.1 | 90.1 | |

$\Delta T$ | 7.3 | 12.2 | 14.2 | 12.1 | 11.5 |

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**MDPI and ACS Style**

Zhang, Y.; Zhang, D.; Wang, D.; Zhang, X. Study on the Heat Reduction Effect of Biomimetic Unidirectional Transporting Channels Inspired by *Nepenthes alata*. *Biomimetics* **2019**, *4*, 70.
https://doi.org/10.3390/biomimetics4040070

**AMA Style**

Zhang Y, Zhang D, Wang D, Zhang X. Study on the Heat Reduction Effect of Biomimetic Unidirectional Transporting Channels Inspired by *Nepenthes alata*. *Biomimetics*. 2019; 4(4):70.
https://doi.org/10.3390/biomimetics4040070

**Chicago/Turabian Style**

Zhang, Yixuan, Deyuan Zhang, Dongyue Wang, and Xiangyu Zhang. 2019. "Study on the Heat Reduction Effect of Biomimetic Unidirectional Transporting Channels Inspired by *Nepenthes alata*" *Biomimetics* 4, no. 4: 70.
https://doi.org/10.3390/biomimetics4040070