#
Fixed Bed Regenerators for HVAC Applications^{ †}

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. Experimental and Theoretical Methods

_{e,i}, T

_{s,i}are the inlet temperature of the exhaust and supply airflows, respectively. ṁ

_{supply}and ṁ

_{exhaut}are the mass flow rate of supply and exhaust air, respectively. The temperature of the air leaving the FBR varies with time and ${\overline{T}}_{s,o}$, and ${\overline{T}}_{e,o}$, are the time-averaged supply and exhaust outlet air temperatures, which are defined as follows:

_{c}and 𝜏

_{h}are the ‘cold period’ and ‘hot period’, respectively.

#### 2.1. Experimental Facility

#### 2.2. Numerical Model

_{p}, 𝑘, U, h, L and T are time, axial coordinate, density, specific heat, thermal conductivity, mean airflow velocity, convective heat transfer coefficient, length of channel and temperature, respectively. Subscripts ‘g’ and ‘m’ are used to represent the gas and matrix variables, respectively. A

_{g}, 𝐴

_{s}and 𝐴

_{m}represent the cross sectional area of the channel, heat transfer surface area and crosssectional area of the exchanger sheet. Appropriate boundary conditions are also implemented to solve the problem [13].

## 3. Results and Discussions

## 4. Conclusions

## Author Contributions

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 2.**(

**a**) Small scale test facility for the performance evaluation of FBRs (

**b**) a schematic of test section and (

**c**) a picture of parallel-plate heat exchanger for the test section.

**Figure 3.**Quasi-steady-state outlet air temperature profile of FBR at the face velocity of 0.7 m/s (a) and at the face velocity of 1.6 m/s (b).

Air channel | Aluminum sheet | ||||||
---|---|---|---|---|---|---|---|

Length (cm) | Width (mm) | Height (cm) | Hydraulic diameter (mm) | Thickness (mm) | Density (kg/m3) | Thermal Conductivity (W/m•K) | Specific heat capacity (J/kg•K) |

20 | 8 | 4 | 7.6 | 0.62 | 2730 | 162 | 903 |

**Table 2.**Operating conditions of two tests for this study with dimensionless groups of NTUo and Cr*.

Test | Volumetric flowrate (L/min) | Hot inlet temperature (°C)/relative humidity (%) | Cold inlet temperature (°C)/relative humidity (%) | Face velocity (m/s) | Re | NTUo | Cr* |
---|---|---|---|---|---|---|---|

1 | 230 | 41.0/7 | 24.3/12 | 0.7 | 398 | 1.65 | 1.40 |

2 | 530 | 41.4/4 | 24.3/13 | 1.6 | 918 | 0.77 | 0.61 |

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**MDPI and ACS Style**

Ramin, H.; Krishnan, E.; Simonson, C.J.
Fixed Bed Regenerators for HVAC Applications. *Proceedings* **2019**, *23*, 4.
https://doi.org/10.3390/proceedings2019023004

**AMA Style**

Ramin H, Krishnan E, Simonson CJ.
Fixed Bed Regenerators for HVAC Applications. *Proceedings*. 2019; 23(1):4.
https://doi.org/10.3390/proceedings2019023004

**Chicago/Turabian Style**

Ramin, Hadi, Easwaran Krishnan, and Carey J. Simonson.
2019. "Fixed Bed Regenerators for HVAC Applications" *Proceedings* 23, no. 1: 4.
https://doi.org/10.3390/proceedings2019023004