Topic
Cooling down
About: Cooling down is a research topic. Over the lifetime, 616 publications have been published within this topic receiving 2750 citations. The topic is also known as: warming down.
Papers published on a yearly basis
Papers
TL;DR: In this article, the authors discuss several solutions to the problem: heating, mixing, differential absorption, inhomogeneous metallicity, and differential absorption with high-resolution X-ray images.
Abstract: Strong evidence for cooling flows has been found in low-resolution X-ray imaging and spectra of many clusters of galaxies. However, high-resolution X-ray spectra of several clusters from the Reflection Grating Spectrometer on XMM-Newton now show a soft X-ray spectrum inconsistent with a simple cooling flow. The main problem is a lack of the emission lines expected from gas cooling below 1–2 keV. Lines from gas at about 2–3 keV are observed, even in a high-temperature cluster such as A1835, indicating that gas is cooling down to about 2–3 keV, but is not found at lower temperatures. Here we discuss several solutions to the problem: heating, mixing, differential absorption and inhomogeneous metallicity. Continuous or sporadic heating creates further problems, including the targeting of the heat at the cooler gas and also the high total energy required. So far there is no clear observational evidence for widespread heating, or shocks, in cluster cores, except in radio lobes which occupy only part of the volume. Alternatively, if the metals in the intracluster medium are not uniformly spread but are clumped, then little line emission is expected from the gas cooling below 1 keV. The low-metallicity part cools without line emission, whereas the strengths of the soft X-ray lines from the metal-rich gas depend on the mass fraction of that gas and not on the abundance, since soft X-ray line emission dominates the cooling function below 2 keV.
186 citations
TL;DR: In this article, two hybrid TMSs including phase change materials (PCM) and cooling water pipes are presented for a Li-ion module with high-capacity prismatic cells, and five other cases (two active, one passive and two naturally ventilated) are constructed and the thermal performance of the seven cases is experimentally evaluated and analyzed.
136 citations
TL;DR: In this paper, the authors developed scalable cellulose-fiber-based composites with excellent self-cleaning and self-cooling capabilities, through air-spraying ethanolic poly(tetrafluoroethylene) (PTFE) microparticle suspensions embedded partially within the micro-sized pores of the cellulose fiber to form a dual-layered structure with PTFE particles atop the paper.
Abstract: Passive daytime radiative cooling (PDRC) involves cooling down an object by simultaneously reflecting sunlight and thermally radiating heat to the cold outer space through the Earth's atmospheric window. However, for practical applications, current PDRC materials are facing unprecedented challenges such as complicated and expensive fabrication approaches and performance degradation arising from surface contamination. Herein, we develop scalable cellulose-fiber-based composites with excellent self-cleaning and self-cooling capabilities, through air-spraying ethanolic poly(tetrafluoroethylene) (PTFE) microparticle suspensions embedded partially within the microsized pores of the cellulose fiber to form a dual-layered structure with PTFE particles atop the paper. The formed superhydrophobic PTFE coating not only protects the cellulose-fiber-based paper from water wetting and dust contamination for real-life applications but also reinforces its solar reflectivity by sunlight backscattering. It results in a subambient cooling performance of 5 °C under a solar irradiance of 834 W/m2 and a radiative cooling power of 104 W/m2 under a solar intensity of 671 W/m2. The self-cleaning surface of composites maintains their good cooling performance for outdoor applications, and the recyclability of the composites extends their life span after one life cycle. Additionally, dyed cellulose-fiber-based paper can absorb appropriate visible wavelengths to display specific colors and effectively reflect near-infrared lights to reduce solar heating, which synchronously achieves effective radiative cooling and esthetic varieties.
129 citations
TL;DR: In this paper, the effects of cooling on the dynamic compressive strength, elastic modulus, P-wave velocity, and failure modes of normal-strength concrete are investigated in detail.
98 citations
TL;DR: In this paper, an electric-conductive paraffin/expanded graphite composite phase change material (cPCM) was used for thermal management of lithium-ion battery in a harsh environment.
92 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 18 |
| 2020 | 12 |
| 2019 | 28 |
| 2018 | 60 |
| 2017 | 45 |
| 2016 | 41 |