Xiaoyan Zhuo¹, Yukun Ji¹, Yatao Ren^1,*, Xuehui Wang², Hong Qi¹

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1701-1720, 2025, DOI:10.32604/fhmt.2025.074045 - 31 December 2025

Abstract Flow and heat transfer characteristics during droplet impact on hot walls are pivotal for elucidating the mechanisms of spray cooling and exploring pathways for heat transfer enhancement. When the wall temperature exceeds the Leidenfrost point, a vapor film forms between the droplet and the wall, rendering the heat transfer process highly complex. Furthermore, for droplet impact on curved walls, the presence of curvature introduces additional factors that modify the spreading behavior of the droplet and necessitate in-depth analysis. Therefore, this work investigates the flow and heat transfer dynamics of droplet impact on hot planes and… More >

Dongmin Wang^1,2,*, Gaoshuai Lin¹

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.1, pp. 299-318, 2023, DOI:10.32604/cmes.2023.027280 - 23 April 2023

Abstract There are five most widely used contact angle schemes in the pseudopotential lattice Boltzmann (LB) model for simulating the wetting phenomenon: The pseudopotential-based scheme (PB scheme), the improved virtual-density scheme (IVD scheme), the modified pseudopotential-based scheme with a ghost fluid layer constructed by using the fluid layer density above the wall (MPB-C scheme), the modified pseudopotential-based scheme with a ghost fluid layer constructed by using the weighted average density of surrounding fluid nodes (MPB-W scheme) and the geometric formulation scheme (GF scheme). But the numerical stability and accuracy of the schemes for wetting simulation remain… More >

Daqin Zhang^1,2, Chufeng Yang³, Huayang Ran^1,2, Juanli Wang^1,2,*, Jintao Wan^1,2,*, Yuhu Li^1,2, Pujun Jin^1,2, Daodao Hu^1,2

Journal of Renewable Materials, Vol.10, No.7, pp. 1797-1811, 2022, DOI:10.32604/jrm.2022.018754 - 07 March 2022

Abstract The development of efficient green flame retardants is an important way to realize more sustainable epoxy thermosets and downstream materials. In this work, a monoepoxide is synthesized through O-glycidylation of eugenol, and then reacted with DOPO (9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide) to obtain a new bio-based flame retardant, DOPO-GE. DOPO-GE is blended with a bisphenol A epoxy prepolymer exhibiting good compatibility and DDS (4,4′-diaminodiphenylsulfone) is used as the curing agent to afford epoxy thermosets. Although DOPO-GE leads to the reduced glass transition temperature of the thermosets, the storage modulus increases considerably. The DOPO-GE-modified thermosets exhibit the high thermal stability… More >

Li Wang^1,2,#, Rongbai Tong^3,#, Juanli Wang^1,2,*, Jintao Wan^1,2,*, Yuhu Li^1,2, Pujun Jin^1,2, Daodao Hu^1,2

Journal of Renewable Materials, Vol.10, No.5, pp. 1349-1364, 2022, DOI:10.32604/jrm.2022.019372 - 22 December 2021

Abstract Quest for bio-based halogen-free green flame retardant has attracted many concerns in recent years. Herein a reactive functional flame retardant containing phosphorus VDP is synthesized from vanillin, 9,10-dihydro-9-oxa-10-phosphophene-10-oxide (DOPO) and phenol via a facile way. VDP is characterized with ¹H NMR, ³¹P NMR, FTIR and Time of Flight Mass Spectrometry, and used as a new reactive flame retardant for bisphenol epoxy thermosets. Thermogravimetry analysis shows that when the VDP loading is only 0.5P% (based on phosphorus content), the residue increases from 14.2% to 21.1% at 750°C in N₂ compare with neat DGEBA. Correspondingly, the limit oxygen index… More >

Yufeng Ma¹, Xuanang Gong¹, Puyou Jia^2,*

Journal of Renewable Materials, Vol.8, No.1, pp. 45-55, 2020, DOI:10.32604/jrm.2020.08621 - 01 January 2020

Abstract In order to improve the comprehensive performance of phenolic foam, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) was grafted with itaconic acid (ITA) (DOPO-g-ITA) to modify microcrystalline cellulose (MCC). DOPO-g-ITA modified MCC (DIMMCC) was used to prepare composite phenolic foam (DCPF). The structures of DIMMCC were verified by Fourier transform infrared spectroscopy (FT-IR). The microstructure and crystalline property were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. Compared with MCC, the crystallinity of DIMMCC was dramatically decreased, but the diffraction peak positions were unchanged. Thermal stability was decreased, and T_i decreased by 45.0°C. The residual carbon (600°C) More >

Yufeng Ma¹, Xuanang Gong¹, Bing Xie¹, Xiang Geng¹, Puyou Jia^2,*

Journal of Renewable Materials, Vol.7, No.10, pp. 1037-1046, 2019, DOI:10.32604/jrm.2019.07454

Abstract In order to improve the mechanical properties without reducing its flame retardancy of phenolic foams (PFs), 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) was introduced in the structure of cashew nut shell liquid (CNSL) to improve its flame retardant, and the product of DOPO grafting CNSL (DOPO-g-CNSL) was obtained to modify phenolic resin, and to prepare DOPO-g-CNSL modified PFs (DCMPFs). The structures of DOPO-g-CNSL were verified by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H-NMR). Compared with CNSL, thermal stability of DOPO-g-CNSL was decreased and Ti decreased by 3.53%, but the residual carbon (800°C) was increased by More >