Study on the Cooling Effect of Asphalt Pavement Blended with Composite Phase Change Materials

Abstract

To explore the cooling effect of phase change materials (PCM) on asphalt pavement, a numerical model of the coupled heat transfer process of a typical monolithic subgrade of the G7 Expressway in the eastern Tianshan mountain area was developed. Three types of paraffin materials (OP55E, OP52E, OP47E) were mixed in a 4:3:3 volume ratio and blended into the asphalt upper layer and overall asphalt layer at volume ratios of 5%, 10%, 15% and 20%. The cooling effect of different PCM addition schemes was simulated and analyzed, and the frequency and duration of asphalt pavement high temperature operation status were also measured. The results showed that: (1) Th addition of PCM in the asphalt layer can effectively reduce the frequency of pavement high temperature rutting damage. The number of days and average daily duration of high temperature on the road surface were both reduced. (2) The cooling effect was positively correlated with the PCM volume mixing ratio, and the temperature drop of the pavement also increased with the increase of the PCM blending ratio. As the PCM mixing ratio increased from 5% to 20%, the initial 75 °C pavement cooled by 1.49 °C and 4.66 °C, respectively, and the number of days and hours of pavement temperature over 70 °C decreased to 4 days and 3.3 h, respectively. (3) The cooling effect of the asphalt upper layer PCM scheme was greater at a small mixing ratio (5%), whereas the performance of the overall asphalt layer PCM blended scheme was effectively promoted by increasing the equivalent heat capacity of system under the large mixing ratio (20%).

Advancements in Phase Change Materials in Asphalt Pavements for Mitigation of Urban Heat Island Effect: Bibliometric Analysis and Systematic Review

“…Conversely, PCM with higher melting points around 50 °C to 60 °C, such as types PEG1000 to PEG8000 [ 12 , 13 , 25 , 26 , 35 , 36 , 37 , 40 , 42 , 62 ], OP55E [ 63 ], stearic acid (SA) [ 11 , 64 ], PCM-43 and PCM-48 [ 46 ], and ceresin wax [ 65 ], could be employed in high-temperature thermal energy storage applications. These are particularly suitable for tropical and temperate locales where summer temperatures can get excessively high, posing a risk to the mechanical integrity of asphalt material.…”

“…Certain materials are inherently solid and do not necessitate a leakage prevention strategy. Solid-to-solid PCM (SS-PCM) are a unique class characterised by their ability to transition from one solid phase to another [ 40 , 55 , 63 , 75 ]. Unlike other PCM, they remain solid throughout their phase transitions, eliminating the need for leakage prevention strategies.…”

“…Specific studies have implemented PCM contents ranging from 3% to 15% in terms of either volume [ 38 ] or mass [ 32 , 63 , 70 , 79 ] of the binder in the asphalt mixture. Some unique combinations have been made by substituting 50% of the fine aggregate with sizes of 0.3–0.6 and 0.15–0.3 mm [ 69 ].…”

“… Dry mixing non-specified [ 98 ] NiTi non-specified Dry mixing 3%, 6%, 9%, and 12% by the weight of the mixture [ 100 ] Nano-CuO non-specified Wet mixing 4% [ 96 ] Paraffin wax materials: OP55E, OP52E, and OP47E Not applicable because solid–solid phase change materials were used. Dry mixing 5%, 10%, 15%, and 20% ( w / w ) [ 63 ] Solid–solid PCM (provided by a commercial company) Not applicable because solid–solid phase change materials were used. Wet mixing 4% and 8% ( w / w ) [ 55 ] Stearic acid (SA)/palmitic acid (PA) binary eutectic phase change material (SA/PA-PCM) Not applicable because solid-liquid phase change materials were used.…”

Assessment of Thermal Performance of Phase-Change Material-Based Multilayer Protective Clothing Exposed to Contact and Radiant Heat

“…For decades, PCMs, due to their useful properties, have been widely used as heat accumulators in installations using renewable energy sources (in particular solar radiation energy-photovoltaic modules) [4][5][6][7]; heat insulators in structural elements of buildings [8][9][10][11][12][13]; temperature stabilizers of food products or medicines (isothermal containers) [14][15][16]; temperature stabilizers of road surfaces [17][18][19]. The use of these materials in multilayer wall structures results in a reduction in daily temperature amplitudes inside the building and a delay in releasing the stored heat.…”