TY - JOUR
TI - A numerical study on heating performance of horizontal and vertical earth-air heat exchangers with equal pipe lengths
AU - Tasdelen Fatih
AU - Dağtekin Ihsan
JN - Thermal Science
PY - 2022
VL - 26
IS - 4
SP - 2929
EP - 2939
PT - Article
AB - In this study, heating performances of horizontal and vertical earth-air heat  exchangers with equal pipe lengths were evaluated in ANSYS FLUENT 19.2  simulation program based on CFD for the winter period of Bitlis, Turkey.  Thermal per­formance analyses regarding vertical and horizontal 3-D-modeled  earth-air heat exchangers were evaluated in steady-state condition of the  simulation program for different values of Re = 5⋅103, 104, 2⋅104, 4⋅104,  6⋅104, 8⋅104, and 105 numbers by using standard k-ε turbulence model.  Numerical results obtained from CFD based simulation program were compared  with a numerical study in the literature, and it was determined that there  was a consistency between the results. The pressure loss and fan power  values of horizontal and vertical earth-air heat exchangers were also  investigated in addition their thermal performances. A good agreement was  found between the pressure loss values obtained from the theoretical and  simulation calculations of both earth-air heat exchangers. Considering the  temperature increases in both earth-air heat exchangers, the highest and  lowest temperature increases were observed in vertical earth-air heat  exchanger with 22.52 K and 10.67 K, respectively. The best thermal  performance was observed in vertical earth-air heat exchanger for 5⋅103,  104, and 2⋅104 values of Reynolds number and in horizontal earth-air heat  exchanger for 4⋅104, 6⋅104, 8⋅104, and 105 values of Reynolds number.