Comparison of Frost and Defrost Performance between Microchannel Coil and Fin-and-Tube Coil for Heat Pump Systems
Abstract
This paper presents a comparison of frost and defrost cycling performance between a microchannel heat exchanger with louvered fin and a fin-and-tube heat exchanger with straight fins employed as outdoor coils of a 14 kW (48 000 Btu/h) heat pump system. In addition to temperature, pressure and flow rate measurements taken at various locations of the systems, the fin-base and tube wall surface temperature were also recorded by using fine-gauge precalibrated thermocouples on the coils. Further, load cells were used to measure the mass of frost accumulation during heating tests. Data showed that the frosting time of the microchannel heat exchanger is more than 50% shorter than for the fin-and-tube heat exchanger, which is chosen as the baseline system. The average heating capacity and system performance over a frost–defrost cycle are also lower for the system with microchannel heat exchangers. Higher frost growth rate was mainly due to augmented temperature difference between air and the surface of the heat exchanger, and preferential frost nucleation sites on the louvered fins and microchannel tubes. Removal of residual water in the microchannel heat exchanger did not improve the frost performance significantly. Blowing nitrogen on the microchannel coil after defrost removed any visible water retained in the coil after the defrost cycle but the cycle time increased only by 4% with respect to wet and frost conditions. The cycle time of the same microchannel coil starting with dry conditions was about 60% longer than the cycle time in wet and frost conditions.
AI snapshot
Written from the paper’s full text.
TL;DR
A 4-ton R22 heat pump was tested with either a louvered-fin microchannel outdoor coil or a straight-fin fin-and-tube coil under ARI frosting conditions, and the microchannel coil frosted much faster and delivered lower capacity and EER. Residual water after defrost, larger air-to-surface temperature differences, and preferential nucleation on louvered fins/microchannel tubes are identified as causes, though water retention alone was not the dominant factor.
Key findings
- Frost cycle time for the microchannel coil under steady periodic (cyclic) conditions was 23m 13s versus 41m 07s for the fin-and-tube coil — about 50% shorter; starting dry, microchannel was 39m 43s versus 49m 13s (25% less).
- Initial frost growth rate was ~0.0086 lb/(lb-ft²-min) for microchannel versus ~0.006 lb/(lb-ft²-min) for fin-and-tube, i.e. about 43% faster in the first 5 minutes; microchannel accumulated ~0.065 lb/(lb-ft²) in ~24 min versus ~0.06 lb/(lb-ft²) in ~40 min for fin-and-tube.
- Blowing nitrogen after defrost removed all visible water (about 95% of water removed vs ~85% drained in normal cyclic operation) but increased cycle time only 4% (24m 25s vs 23m 13s); the dry-start cycle was about 60% longer than the wet/cyclic cycle.
- Average capacity of the microchannel coil over its cycle was about 27% less than the dry fin-tube case and 22% less than the cyclic fin-tube case; EER was about 13% lower. Heating capacity degradation at end of frosting was ~16% (fin-tube dry), ~19% (fin-tube wet), and ~25% (microchannel).
Methods
- A 4-ton R22 unitary heat pump was placed between two environmental chambers; outdoor chamber held at ARI conditions of 35/33°F (1.67/0.56°C) DB/WB, indoor at 70°F DB with ~1800 cfm across the indoor coil. The fin-and-tube coil was the baseline and was replaced by a microchannel coil of similar (4-ton) capacity with ~6% less face area.
- Five tests: fin-tube dry and cyclic, microchannel dry, cyclic, and nitrogen-blow; defrost was demand-initiated from coil-surface-to-air temperature difference held above a threshold for ~4.5 minutes.
- Instrumentation included three load cells (±0.6 lb accuracy) to weigh frost, a coriolis flow meter, pressure transducers and thermocouples (Table 1), and 16 fine-gauge T-type thermocouples on fin and tube surfaces; a videoscope recorded frost growth. Capacity, COP and EER were computed from air-side measurements, and results were normalized into dimensionless form to protect proprietary data.
Limitations
- Stated: the effect of the larger air-to-surface temperature difference on frost growth rate requires further investigation to quantify; controlled wind tunnel experiments are planned to study the frost mechanism in microchannel coils.
- Stated: load cells were sensitive to refrigerant shift between modes, loss of downward fan force during defrost, and transient loading of the flexible duct; calibration estimated these effects within ±0.6 lb.
- Evident from the text: results come from a single 4-ton R22 unit with one coil of each type, and data are presented in dimensionless/normalized form, so absolute capacity and EER values are not reported; the paper also notes that frost times combine water retention, lower saturation pressure inside microchannel tubes, and refrigerant distribution, which the test matrix does not fully separate.
Model-written summary. Check it against the paper before relying on it.
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Claims the paper makes
0 of 1 cited sources checked · 0 supported · 0 flagged
- Findingown data§ 4.1.Frost Cycle Time · p. 6
A microchannel heat exchanger with dry starting conditions had a frost cycle time which is 25% less than a fin-tube coil starting dry.
“Thus a microchannel heat exchanger with dry starting conditions had a frost cycle time which is 25% less than a fin-tube coil starting dry.”
Quote in the paperSubstantial claim - Findingown data§ 4.3. Coil Surface Temperatures · p. 7
The temperature difference between inlet air and the surface of the coil is higher for the microchannel coil than for the fin-and-tube coil.
“The temperature difference between inlet air and the surface of the coil is higher for the microchannel coil than for the fin-and-tube coil.”
Quote in the paperNot a substantial claim - Findingown data§ 4.2. Frost Weight · p. 6
The frost growth rate in the microchannel heat exchanger is higher than in the fin-and-tube heat exchanger.
“However, the steeper slope of the microchannel curve shows that the rate of frost growth of the microchannel was significantly higher than the rate of frost growth of the fin-and-tube.”
- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
“It was also observed that the frost growth rate in the microchannel heat exchanger is higher compared to the fin-tube coil.”
Quote in the paperSubstantial claim - Also stated in: § 5. CONCLUSIONS · p. 8 · plain
- Findingown data§ 4.1.Frost Cycle Time · p. 6
The heating capacity degradation for the microchannel heat exchanger is about 25%.
“For the microchannel heat exchanger, the heating capacity degradation was about 25%.”
Quote in the paperSubstantial claim - Findingown data§ 4.4. Performance Evaluation · p. 8
The average capacity of the microchannel coil over its entire cycle is about 22% less than the cyclic fin-tube coil.
“The average capacity of the microchannel coil over its entire cycle is about 27% less than the dry fin-tube coil and 22% less than the cyclic fintube case.”
- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
“The average capacity of the microchannel coil over its entire cycle was lower by about 22% with respect to the fin-tube coil.”
Quote in the paperSubstantial claim - Also stated in: § 5. CONCLUSIONS · p. 8 · plain
- Findingown data§ ABSTRACT · p. 2
The cycle time of the same microchannel starting with dry condition was about 60% longer than the cycle time in wet and frost conditions.
“The cycle time of the same microchannel starting with dry condition was about 60% longer than the cycle time in wet and frost conditions.”
- Also stated in: § 4.1.Frost Cycle Time · p. 5 · plain
“The cycling time of the microchannel starting dry was about 60% longer than the same coil starting wet after a defrost cycle.”
Quote in the paperSubstantial claim - Also stated in: § 4.1.Frost Cycle Time · p. 5 · plain
- Findingown data§ 4.4. Performance Evaluation · p. 8
The average capacity of the microchannel coil over its entire cycle is about 27% less than the dry fin-tube coil.
“The average capacity of the microchannel coil over its entire cycle is about 27% less than the dry fin-tube coil and 22% less than the cyclic fintube case.”
Quote in the paperSubstantial claim - Findingown data§ 4.2. Frost Weight · p. 7
The growth of the frost layer begins from the microchannel tubes and progresses irregularly toward the fins.
“The growth of frost layer begins from the microchannel tubes and progress irregularly toward the fins.”
Quote in the paperNot a substantial claim - Findingown data§ 4.2. Frost Weight · p. 6
Frost accumulates during the first part of the heating cycle, approximately during the first 10 minutes.
“The frost weight measurements of Figure 3 also indicate that the frost accumulates during the first part of the heating cycle, that is, approximately during the first 10 minutes.”
Quote in the paperNot a substantial claim - Findingown data§ ABSTRACT · p. 2
The frosting time of the microchannel heat exchanger is more than 50% shorter than that of the fin-and-tube heat exchanger used as the baseline system.
“Data showed that the frosting time of the microchannel heat exchanger is more than 50% shorter than for the finand-tube heat exchanger, which is chosen as the baseline system.”
- Also stated in: § 4.1.Frost Cycle Time · p. 6 · plain
“Microchannel heat exchanger operating under steady periodic conditions (test #4) performed even worse with about 50% less frost cycle time compared to the fin-and-tube heat exchanger operating under steady periodic conditions (test #2).”
- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
“The fin and tube heat exchanger had considerably longer time between defrost cycles, and about double than the microchannel coil used in our experiments.”
Quote in the paperSubstantial claim - Also stated in: § 4.1.Frost Cycle Time · p. 6 · plain
- Findingown data§ 4.2. Frost Weight · p. 6
During the first 5 minutes of the heating cycle, the frost growth rate of the microchannel heat exchanger is about 43% faster than that of the fin-and-tube heat exchanger.
“During the first 5 minutes of the heating cycle, the rate of frost growth of fin-and-tube is about 0.006 lb/(lb-ft 2 -min) while the rate is about 0.0086 lb/(lb-ft 2 -min) for microchannel. This suggests that initially frost growths about 43% faster in microchannel than in fin-and-tube heat exchangers.”
Quote in the paperSubstantial claim - Findingown data§ 4.2. Frost Weight · p. 6
The fin-and-tube heat exchanger under both dry and steady periodic conditions accumulated approximately the same amount of frost before going into defrost.
“Fin-and-tube heat exchanger under both dry and steady periodic conditions accumulated approximately same amount of frost before going into defrost.”
Quote in the paperNot a substantial claim - Findingown data§ 4.1.Frost Cycle Time · p. 5
The frost time of the microchannel heat exchanger does not increase significantly when the retained water is blown off of the coil using pressurized nitrogen gas.
“The frost time of microchannel heat exchanger does not increase significantly when the retained water is blown off of coil using pressurized nitrogen gas (test #6).”
Quote in the paperSubstantial claim - Findingown data§ 4.3. Coil Surface Temperatures · p. 7
The local microchannel tube wall and corresponding fin surface temperatures are significantly lower at the inlet of the coil.
“The local microchannel tube wall and corresponding fin surface temperatures are significantly lower at the inlet of the coil.”
Quote in the paperNot a substantial claim - Findingown data§ 4.4. Performance Evaluation · p. 8
For all three cases the average capacity increases initially and flattens out in the final stages of the frost growth period.
“For all the three cases the average capacity increases initially and flattens out in the final stages of frost growth period.”
Quote in the paperNot a substantial claim - Findingown data§ 4.4. Performance Evaluation · p. 8
The EER of the heat pump system with the microchannel coil is about 13% lower than the same unit with the fin-and-tube coil.
“The EER of the heat pump system with microchannel coil is also about 13% lower than the same unit with fin-and-tube coil.”
- Also stated in: § 4.4. Performance Evaluation · p. 8 · plain
“The EER of the heat pump system with microchannel coil is also about 13% lower than the same unit with fin-and-tube coil”
Quote in the paperSubstantial claim - Also stated in: § 4.4. Performance Evaluation · p. 8 · plain
- Interpretationown data§ 4.3. Coil Surface Temperatures · p. 8
Frosting on the microchannel coil is not uniform.
“This suggests that the frosting on the microchannel coil is not uniform.”
Quote in the paperSubstantial claim - Interpretationnone given§ 4.1.Frost Cycle Time · p. 6
The frost times shown in Table 4 are a combination of the effect of water retention in the heat exchangers, lower saturation pressure inside microchannel tubes, and refrigerant distribution.
“It must be noted that the frost times shown in Table 4 are a combination of the effect of water retention in the heat exchangers, lower saturation pressure inside microchannel tubes, and refrigerant distribution.”
Quote in the paperSubstantial claim - Interpretationown data§ 4.1.Frost Cycle Time · p. 5
Water retention is not the primary factor that impacts the frosting cycle time.
“This suggests that water retention is not the primary factor that impacts the frosting cycle time.”
Quote in the paperSubstantial claim - Interpretationreasoning§ 4.3. Coil Surface Temperatures · p. 7
Early initiation of frost growth will lead to a reduction in time between defrost cycles.
“Early initiation of frost growth will lead to a reduction in time between defrost cycles.”
Quote in the paperNot a substantial claim - Study design and conductown data§ 4.2. Frost Weight · p. 6
From the calibration data, a curve fit approach estimated the hysteresis of the load cell and the load induced by the flexible duct to be within ±0.6 lb.
“From the calibration data, a curve fit approach was used to estimate the hysteresis of the load cell and the load induced by the flexible duct. These were found to be within ± 0.6 lb.”
Quote in the paperNot a substantial claim - Interpretationown data§ 4.3. Coil Surface Temperatures · p. 8
Frost grows uniformly on the entire face area of the fin-tube coil.
“Similar temperature profiles at the inlet and the outlet (as shown in Fig 5(a)) suggests that frost grows uniformly on the entire face area of the fin tube coil.”
Quote in the paperSubstantial claim - Interpretationown data§ 4.3. Coil Surface Temperatures · p. 8
The frost growth pattern in fin-tube and microchannel heat exchangers are quite different.
“The weight measurements and local temperature curves together suggest that the frost growth pattern in fin-tube and microchannel heat exchangers are quite different.”
- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
“The frost growth patterns were also found to be quite different for fin-tube and microchannel coils.”
Quote in the paperSubstantial claim - Also stated in: § 5. CONCLUSIONS · p. 8 · plain
- May combine two claims. 15
- Classified as probably not a substantial claim. 7
May combine two claims.
Findingown data§ 4.1.Frost Cycle Time · p. 5With nitrogen blowing about 95% of the water was removed from the coil, while in cyclic operations without nitrogen blowing about 85% of the water drains from the coil.
“With Nitrogen blowing about 95% of the water was removed from the coil while in cyclic operations without Nitrogen blowing about 85% of the water drains from the coil.”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data§ 4.1.Frost Cycle Time · p. 5The microchannel coil starting dry had a frost cycle time of 39m 43s and a defrost time of about 2m 50s.
“The microchannel coil starting dry, that is, test #3 in Table 3, had a frost cycle time of 39m 43 s and a defrost time of about 2m 50s.”
Quote in the paperNot a substantial claimMay combine two claims.
Findingown data§ 4.2. Frost Weight · p. 6The fin-and-tube heat exchanger builds up about 0.06 lb/(lb-ft2) of frost in about 40 minutes under cyclic conditions, and in about 50 minutes under dry starting conditions.
“Fin-and-tube has the lowest frost growth rate and it builds up about 0.06 lb/(lbft 2 ) in about 40 minutes (50m for dry starting condition).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data§ 4.2. Frost Weight · p. 6The microchannel heat exchanger accumulated about 0.065 lb/(lb-ft2) of frost in approximately 24 minutes under cyclic conditions, and in about 40 minutes under dry starting conditions.
“Microchannel heat exchanger accumulated about 0.065 lb/(lb-ft 2 ) of frost in approximately 24 minutes (40m for dry starting condition).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data§ 4.1.Frost Cycle Time · p. 6The fin-tube coil starting dry had a frost cycle time of 49m 13s and a defrost time of 2m 02s.
“Fin-tube coil starting dry on the other hand had a frost cycle time of 49m 13s and a defrost time of 2m 02s.”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data§ 4.1.Frost Cycle Time · p. 6The capacity reduction for the fin-tube heat exchanger at the end of the heating period is around 16% for the dry coil and 19% for the wet coil.
“The capacity reduction for the fin-tube heat exchanger at the end of heating period is around 16% for the dry coil and 19% for the wet coil.”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data§ ABSTRACT · p. 2Blowing nitrogen on the microchannel coil after defrost removed any visible water retained in the coil, but the cycle time increased only by 4% with respect to wet and frost conditions.
“Blowing nitrogen on the microchannel coil after defrost removed any visible water retained in the coil after the defrost cycle but the cycle time increased only by 4% with respect to wet and frost conditions.”
- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
“Blowing nitrogen on the microchannel coil removed all visible water retained in the coil after the defrost cycle but the time between defrost cycles increased only by 4% with respect to wet and frost conditions.”
Quote in the paperSubstantial claim- Also stated in: § 5. CONCLUSIONS · p. 8 · plain
May combine two claims.
Findingnone given§ 4.4. Performance Evaluation · p. 8The drops of the capacity are due to the defrost stage, at which point the heating capacity of the unit becomes zero.
“The drops of the capacity is due to the defrost stage, at which point the heating capacity of the unit becomes zero.”
Quote in the paperNot a substantial claimMay combine two claims.
Findingown data§ 4.1.Frost Cycle Time · p. 5The cyclic, steady periodic behavior of the same microchannel unit during test #4 had a frost cycle time of 23m 13s while the defrost time was 3m 30s.
“The cyclic, steady periodic behavior of the same unit during test #4 had a frost cycle time of 23m 13s while the defrost time was 3m 30s.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductreasoning§ 3. DATA REDUCTION · p. 4Indoor fan power was not accounted for in the COP because only the outdoor coil was replaced between tests while the indoor coil was the same for all tests.
“Indoor fan power was not accounted for in the COP because only the outdoor coil was replaced with between tests while the indoor coil was the same for all tests.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Interpretationreasoning§ 4.3. Coil Surface Temperatures · p. 7The high temperature difference between inlet air and coil surface impacts the frost growth rate, but further investigation is necessary to quantify this effect.
“This high temperature difference impacts the frost growth rate but further investigation is necessary to quantify this effect.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing), S4 (based).
Interpretationnone given§ 4.1.Frost Cycle Time · p. 5The significant amount of water visibly retained in the coil during normal operation does not practically contribute to shortening the heating period.
“The significant amount of water that is visibly retained in the coil during normal operation does not practically contribute to shortening the heating period.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown data§ 2. EXPERIMENTAL SETUP · p. 3The load cells were calibrated in-situ with standardized weights and the accuracy on the load cells was determined to be ±0.6 lb.
“The load cells were calibrated in-situ with standardized weights and the accuracy on the load cells was determined to be ±0.6 lb [28.3 g].”
Quote in the paperNot a substantial claimMay combine two claims.
Premisecitation§ 4.3. Coil Surface Temperatures · p. 7Frost formation on the heat exchanger depends on the heat exchanger surface temperature, and lower surface temperature initiates frost growth early.
“Frost formation on the heat exchanger depends on the heat exchanger surface temperature. Lower surface temperature initiates frost growth early (Tao et al, 1993).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites Tao et al, 1993
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).
Interpretationnone given§ 4.1.Frost Cycle Time · p. 5The thin layer of water or small water droplets acts as preferential nucleation sites for frost formation.
“The thin layer of water or small water droplets is believed to act as preferential nucleation sites for the frost formation.”
Quote in the paperNot a substantial claimClassified as probably not a substantial claim.
Study design and conductown data§ 4.2. Frost Weight · p. 6A calibration procedure was carried out before the experiments to estimate the influence of system-related factors on the readings from the load cells.
“A calibration procedure was carried out before the experiments to estimate the influence of these factors on the readings from the load cells.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown data§ 2. EXPERIMENTAL SETUP · p. 3All thermocouples were calibrated in-situ, and the in-situ calibration improved the accuracy on the thermocouples to within ±0.4°F.
“All the thermocouples were calibrated in-situ. The in-situ calibration resulted in improving the accuracy on the thermocouples to within ±0.4°F [0.2°C].”
Quote in the paperNot a substantial claimMay combine two claims.
Interpretationown data§ 5. CONCLUSIONS · p. 8The surface temperatures of the microchannel heat exchanger are lower, promoting high heat transfer rate but also high frost growth rate.
“The surface temperatures are lower, promoting high heat transfer rate but also high frost growth rate.”
Quote in the paperSubstantial claim
The paper relies on this without support.
The local temperature of fins and wall tubes at various locations in the coil is the key parameter to understand the heat and mass transfer occurring during frost growth and frost melt.
“Local temperature of fins and wall tubes at various locations in the coil is the key parameter to understand the heat and mass transfer occurring during frost growth and frost melt.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
When a microchannel heat exchanger works in winter, frost forms and accumulates faster on the fin surface, leading to decreased airflow rate, increased thermal resistance, and reduced heating capacity of heat pump units.
“However, when the MCHX works in the winter, the frost will form and accumulate faster on the fin surface [6,7], which will lead to a decrease in airflow rate and an increase in the thermal resistance, thus reducing the heating capacities of the heat pump units [8][9][10].”
From Performance Improvement of Microchannel Heat Exchangers with Modified Louver Fins under Frosting Conditions (2023) · cites this paper as [6]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Cyclic and nitrogen-blow tests are assigned the wrong numbers
MinorThe comparison calls the microchannel cyclic test #5 and the nitrogen-blow test #6. Table 4 labels them tests #4 and #5, respectively; no test #6 appears in the test matrix.
“The comparison between test #5 (microchannel cyclic) and test #6 (microchannel N2 blow) aims to isolate the effect of excess water retention at the end of the defrost cycle.”
“| | Fin-Tube- Dry (Test #1) | Fin-Tube- Cyclic (Test #2) | Microchannel Dry (Test #3) | Microchannel- Cyclic (Test #4) | Microchannel- N 2 Blow (Test #5) |”
Dry-coil frosting time reduction is not 25%
MinorThe dry-coil frost times in Table 4 are 49m 13s and 39m 43s. The latter is about 19.3% shorter than the former, rather than 25%.
“Thus a microchannel heat exchanger with dry starting conditions had a frost cycle time which is 25% less than a fin-tube coil starting dry.”
“| Frost time | 49m 13s | 41m 07s | 39m 43s | 23m 13s | 24m 25s |”
Abstract overstates the reduction in frosting time
MinorTable 4 gives cyclic frost times of 41m 07s for the fin-and-tube coil and 23m 13s for the microchannel coil. That makes the microchannel time about 43.5% shorter, not more than 50% shorter.
“Data showed that the frosting time of the microchannel heat exchanger is more than 50% shorter than for the finand-tube heat exchanger, which is chosen as the baseline system.”
“| Frost time | 49m 13s | 41m 07s | 39m 43s | 23m 13s | 24m 25s |”
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Self-citationPreparation and Anti-frost Performance of PDMS-SiO2/SS Superhydrophobic Coating
Jia, L., Sun, J., Li, X., Zhang, X., Chen, L., & Tian, X. (2020) · Coatings · doi:10.3390/coatings10111051 · Cited by 22 · see citing works
Ma, D., Chen, Q., & Yan, G. F. (2024) · Applied Thermal Engineering · doi:10.1016/j.applthermaleng.2024.123359 · Cited by 22 · see citing works
Experimental analysis of an air–water heat pump with micro-channel heat exchanger
Brignoli, R., Cecchinato, L., & Zilio, C. (2013) · Applied Thermal Engineering · doi:10.1016/j.applthermaleng.2012.08.027 · Cited by 21 · see citing works
Experimental Investigation of Frost Growth on Microchannel Heat Exchangers
Moallem, E., Cremaschi, L., & Fisher, D. E. (2010) · Cited by 16 · see citing works
Self-citationLiu, N., Li, D., He, J., Li, K., Tian, Y., & Zhang, H. (2024) · Applied Thermal Engineering · doi:10.1016/j.applthermaleng.2024.123339 · Cited by 14 · see citing works
Moallem, E., Hong, T., Cremaschi, L., & Fisher, D. E. (2013) · Science and Technology for the Built Environment · doi:10.1080/10789669.2013.781056 · Cited by 11 · see citing works
Self-citationMoallem, E., Hong, T., Cremaschi, L., & Fisher, D. E. (2013) · Science and Technology for the Built Environment · doi:10.1080/10789669.2013.812500 · Cited by 9 · see citing works
Self-citationXiong, T., Zhao, T., Liu, G., Zhao, L., Jin, J., Gao, Q., & Yan, G. (2024) · Journal of Building Engineering · doi:10.1016/j.jobe.2024.109521 · Cited by 7 · see citing works
Xiong, T., Liu, G., & Yan, G. (2023) · Applied Sciences · doi:10.3390/app13116378 · Cited by 6 · see citing works
Safikhani, H., Esmaeili, F., & Rezvani, S. (2025) · International Journal of Refrigeration · doi:10.1016/j.ijrefrig.2025.04.016 · Cited by 5 · see citing works
Frosting performance of fin-and-tube evaporators with small copper tubes diameter.
Cremaschi, L., Moallem, E., Fisher, D. E., Hong, T., & Padhmanabhan, S. (2012) · Purdue e-Pubs (Purdue University System) · Cited by 3 · see citing works
Self-citationHAN, Z. W., Meng, X., LIN, M., Zhang, Y. H., YANG, J., & WANG, Y. R. (2014) · International Journal of Air-Conditioning and Refrigeration · doi:10.1142/s2010132514400045 · Cited by 2 · see citing works
Study of frost growth on heat exchangers used as outdoor coils in air source heat pump systems
Sankaranarayanan, K. (2011) · Cited by 2 · see citing works
Hrnjak, P., Zhang, P., & Rennels, C. (2012)
Khameneh, P. M., Mirzaie, I., Pourmahmoud, N., Rahimi, M., & Majidyfar, S. (2011)
Moallem, E., Hong, T., & Cremaschi, L. (2012)
Self-citationFrost induced design challenges for heat pump heating and cooling efficiency penalties
O'Neill, N. F., Minh, J., Ding, C., & Shah, N. (2025) · Science and Technology for the Built Environment · doi:10.1080/23744731.2025.2511556
- Authors
- PADHMANABHAN, S., CREMASCHI, L., & FISHER, D.
- Affiliations
- Johnson Controls (United States) (US)
- Oklahoma State University (US)
- ORCID
- CREMASCHI, LORENZO
- Venue
- International Journal of Air-Conditioning and Refrigeration
- Published
- 2011-12
- Volume
- 19
- Issue
- 04
- Pages
- 273-284
- ISSN
- 2010-1325 (ISSN-L)
- 2010-1333
- OpenAlex
- W2132579775
- Cited by
- 29
- References
- 14
- Citations by year
- 2025: 2 · 2024: 3 · 2023: 1 · 2020: 1 · 2018: 1 · 2017: 1 · 2016: 1 · 2015: 2 · 2014: 3 · 2013: 2 · 2012: 7
- FWCI
- 8.50
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- International Journal of Air-Conditioning and Refrigeration (publishedVersion)
- Funders
- Oklahoma Center for the Advancement of Science and Technology
- Topics
- Physical Sciences › Engineering › Mechanical Engineering › Refrigeration and Air Conditioning Technologies
- Physical Sciences › Engineering › Mechanical Engineering › Heat Transfer and Optimization
- Physical Sciences › Engineering › Mechanical Engineering › Adsorption and Cooling Systems
- Keywords
- frost formation, microchannel heat exchangers, finned tube heat exchanger, heat pumps, louvered fins, frost accumulation, heating capacity
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