Thông tin chung

  English

  Đề tài NC khoa học
  Bài báo, báo cáo khoa học
  Hướng dẫn Sau đại học
  Sách và giáo trình
  Các học phần và môn giảng dạy
  Giải thưởng khoa học, Phát minh, sáng chế
  Khen thưởng
  Thông tin khác

  Tài liệu tham khảo

  Hiệu chỉnh

 
Số người truy cập: 37,616,335

 Velocity fields and mixing properties of swirling double-concentric jets using two separated circular disks as center bodies
Tác giả hoặc Nhóm tác giả: Le Minh Duc, Ching Min Hsu, Rong Fung Huang
Nơi đăng: Experimental Thermal and Fluid Science (SCI); Số: 93;Từ->đến trang: 73-85;Năm: 2018
Lĩnh vực: Khoa học công nghệ; Loại: Bài báo khoa học; Thể loại: Quốc tế
TÓM TẮT

ABSTRACT
This study investigated the flow features, turbulence characteristics, and mixing properties of swirling double-concentric jets by using two circular disks in tandem as the center body. The laser-assisted smoke-wire technique was used for flow visualization, particle image velocimetry (PIV) was utilized to investigate the velocity field, and the tracer gas concentration detection method was used to examine mixing property. When one circular disk was used as the centerbody, the flow patterns obtained through flow visualization and PIV measurement revealed two pairs of counter-rotating vortices existing in the near wake. The central jet penetrated the recirculation zone without any reversal, so low mixing between the central jet fluids and the annular swirling jet was observed. When two circular disks in tandem were used as the centerbody, the central jet momentum was transferred from the axial direction to the radial direction, and then it was dispersed and diffused into the annular swirling jet in the wake. Two flow modes were identified in the near wake: close-top toroidal wake and turbulent reverse-flow wake. In both characteristic flow modes, flows on the central axis were reversed in the near wake region. The axial and radial turbulence intensities were increased, and large values were observed inside the recirculation zone. Consequently, the carbon dioxide released from the central jet exit detected in the wake of the two-disk case was drastically lower than that of the one-disk case. The mixing process in the case of the two circular disks was significantly improved compared with that in the case of the single circular disk. The maximum improvement that could be attained was about 96%.
[ https://www.sciencedirect.com/science/article/pii/S0894177717304090 ]
© Đại học Đà Nẵng
 
 
Địa chỉ: 41 Lê Duẩn Thành phố Đà Nẵng
Điện thoại: (84) 0236 3822 041 ; Email: dhdn@ac.udn.vn