# Designing a Turning Guide Vane Using CFD for an Economizer of a Non-Furnace Boiler

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## Abstract

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## 1. Introduction

_{2}emissions, it is essential to increase the efficiency of energy-consuming facilities while actively introducing renewable energy sources [2]. The International Energy Agency estimates that the implementation of energy-efficiency measures in industrial boilers can result in a reduction of approximately nine gigatons of CO

_{2}emissions by 2040 [3]. Since most industrial boilers are of the fire-tube or water-tube type, it is important to increase their efficiency [4,5].

## 2. Non-Furnace Boilers and Numerical Methods

^{3}/h of fuel is equal to 3187.06 kg/h of flue gas.

^{−5}, and it took about 1000 steps to converge.

## 3. Results

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**Non-furnace boiler with an economizer; (

**a**) 3D shape of the system; (

**b**) cross section of the economizer and the computational domain.

**Figure 2.**Economizer designs to improve flow uniformity: (

**a**) the original design; (

**b**) installation of corbels and guide vanes.

**Figure 5.**Experimental setup: (

**a**) schematic diagram; (

**b**) photograph of the non-furnace boiler; (

**c**) economizer with temperature sensors.

**Figure 8.**Two turning guide vane designs for heat and flow uniformity in the economizer: (

**a**) TGV 1; (

**b**) TGV 2.

**Figure 10.**Temperature distributions inside the economizer: (

**a**) without the baffle; (

**b**) with the existing baffle; (

**c**) with TGV 1; (

**d**) with TGV 2.

Water mass flow | 0.838 kg/s |

Water inlet temperature | 15 °C |

Water outlet temperature | 79.6 °C |

Natural gas fuel mass flow | 206 Nm^{3}/h |

Flue gas inlet temperature | 254.62 °C |

Flue gas outlet temperature | 66.6 °C |

Tube outside diameter (D_{o}) | 34 mm |

Tube inside diameter (D_{i}) | 28 mm |

Transverse spacing (X_{t}) | 66.2 mm |

Longitudinal spacing (X_{l}) | 66 mm |

Fin length (F_{l}) | 11 mm |

Fin thickness (F_{t}) | 0.8 mm |

Fin pitch (F_{p}) | 3.2 mm (250 fins per m) |

Free-flow area/frontal area | 0.512 |

Total gas-side surface area/total volume | 178.91 m^{2}/m^{3} |

Chemical Composition | Mole Fraction |
---|---|

Methane (CH_{4}) | 0.88484 |

Ethane (C_{2}H_{6}) | 0.09284 |

Propane (C_{3}H_{8}) | 0.01405 |

Butane (C_{4}H_{10}) | 0.00812 |

Row 19 | (16.49–15 °C) T_{m} = 15.745 °C |

Density | 1000.31 kg/m^{3} |

Kinematic viscosity | 1.11 × 10^{−6} m^{2}/s |

Specific heat | 4178.83 J/kgK |

Prandtl number | 7.86 |

Velocity | 0.15118 m/s |

Reynolds number | 3802.34 |

Row 1 | (73.86–68.08 °C) T_{m} = 70.97 °C |

Density | 978.48 kg/m^{3} |

Kinematic viscosity | 4.08 × 10^{−7} m^{2}/s |

Specific heat | 4182.51 J/kgK |

Prandtl number | 2.51 |

Velocity | 0.15455 m/s |

Reynolds number | 10,604.33 |

Parameter | Range | Current Value |
---|---|---|

Flow condition | $1100\le {R}_{{D}_{h}}\le 18,000$ | 2,344.61–3,062.29 |

Outer diameter (D_{O}) | 11.1–40.9 mm | 34 mm |

Fin pitch (F_{p}) | 246–768 fins/m | 250 fins/m |

$0.13\le \frac{{F}_{p}-{F}_{t}}{{F}_{l}}\le 0.63$ | $\frac{{F}_{p}-{F}_{t}}{{F}_{l}}=0.29$ | |

$1.01\le \frac{{F}_{p}-{F}_{t}}{{F}_{t}}\le 7.62$ | $\frac{{F}_{p}-{F}_{t}}{{F}_{t}}=4$ | |

$0.09\le \frac{{F}_{l}}{{D}_{o}}\le 0.69$ | $\frac{{F}_{l}}{{D}_{o}}=0.32$ | |

$0.011\le \frac{{F}_{t}}{{D}_{o}}\le 0.15$ | $\frac{{F}_{t}}{{D}_{o}}=0.0235$ | |

$1.54\le \frac{{X}_{t}}{{D}_{o}}\le 8.23$ | $\frac{{X}_{t}}{{D}_{o}}=1.95$ |

Parameter | No Baffle | Original Baffle | TGV 1 | TGV 2 |
---|---|---|---|---|

Q (W) | 143 | 163 | 199 | 199 |

ΔP (Pa) | 37.9 | 43.5 | 53.0 | 51.8 |

(Q/Q_{s})/(ΔP/ΔP_{s})^{1/3} | 1 | 1.09 | 1.24 | 1.26 |

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**MDPI and ACS Style**

AM, C.Q.; Ahn, J.
Designing a Turning Guide Vane Using CFD for an Economizer of a Non-Furnace Boiler. *Processes* **2023**, *11*, 1617.
https://doi.org/10.3390/pr11061617

**AMA Style**

AM CQ, Ahn J.
Designing a Turning Guide Vane Using CFD for an Economizer of a Non-Furnace Boiler. *Processes*. 2023; 11(6):1617.
https://doi.org/10.3390/pr11061617

**Chicago/Turabian Style**

AM, Chaerul Qalbi, and Joon Ahn.
2023. "Designing a Turning Guide Vane Using CFD for an Economizer of a Non-Furnace Boiler" *Processes* 11, no. 6: 1617.
https://doi.org/10.3390/pr11061617