Supplemental data for: The effects of outdoor air-side fouling on frost growth and heat transfer characteristics of a microchannel heat exchanger: an experimental study
Description
We investigated the frost formation and heat transfer rates under different inlet air relative humidities (2 cases), initial air face velocities(2 cases), and fouling levels (4 cases). We selected the following condition as our baseline: R= 75%, v=1.0 m/s (S=2510 rpm), clean surface. While studying the effects of one parameter on the performance of the heat exchanger, all other parameters were kept constant. For example, we only increase the inlet RH from baseline (R=75%) to R= 85% for R85 condition. There are eight data sheets in this file, all of them have the same column names. Therefore, we only selected “Baseline” sheet to explain each column meaning: 1. Sensor monitoring variable columns: (A-J). The 1st column (A) is testing time, the interval of each row is one minute. The 2nd (B) and 3rd (C) columns are inlet air temperature parameters, representing inlet air dry-bulb and wet-bulb temperatures, respectively. The 4th (D) column is the air pressure drop across the coil. The 5th (E) column is the air volumetric flow rate across the coil. The 6th (F) column is the anti-freezing solution outlet temperature leaving the coil. The 7th (G) column is the anti-freezing solution inlet temperature entering the coil. The 8th (H) column is the outlet air average temperature of nine RTD sensors downstream of the coil. The 9th (I) and 10th (J) columns are outlet air RH sensors downstream of nine RTD sensors, representing outlet air dry-bulb temperature and relative humidity, respectively. 2. Resultant variable columns: (A-J). The 11th column (K) is inlet air humidity ratio, calculated by inlet air dry-bulb ratio (column B) and wet-bulb (column C) temperatures. The 12th column (L) is the outlet air humidity ratio, calculated by the RH sensor’s outlet air temperature (column I) and relative humidity (column J). The 13th column (M) is the outlet air specific volume, calculated by outlet air humidity ratio (column L) and outlet air temperature (column I). The 14th column (N) is the dry air mass flow rate, calculated by air volumetric flow rate (column E) and outlet air specific volume (column M). The 15th column (O) is inlet air specific enthalpy, calculated by dry air mass flow rate (column N), inlet air dry-bulb temperature (column B) and humidity ratio (column K). The 16th column (P) is outlet air specific enthalpy, calculated by dry air mass flow rate (column N), outlet air dry-bulb temperature downstream of the coil (column H) and humidity ratio (column L). The 17th column (Q) is the heat transfer rate, calculated by dry air mass flow rate (column N), inlet (column O) and outlet (column P) air specific enthalpy. The 18th column (R) is the frost formation rate, calculated by dry air mass flow rate (column N), inlet (column K) and outlet (column L) air humidity ratio. The 19th column (S) is accumulated frost mass, calculated by integrating the frost formation rate (column R) over time.