TY - GEN
T1 - The effects of the distance between nozzle and substrate on cold gas dynamic spray process
AU - Li, Longjian
AU - Cui, Wenzhi
AU - Chen, Qinghua
AU - Jen, Tien Chien
AU - Liao, Quan
PY - 2005
Y1 - 2005
N2 - In this paper, numerical simulations were performed for the gas-particle two phase flow in the cold gas dynamic spray process to investigate the acceleration of micro- and nano-particles with diameters ranging from 100nm to 50μm, Nitrogen (N2) and Helium (He) were chosen as the carrier gas, respectively. The acceleration of carrier gas to particles in the De-Laval-Type supersonic nozzle was strongly dependent on the characteristics of flow field, as well as the densities and the size of the particles. Two kind of particles Copper (Cu) and Platinum (Pt) were chosen as the spraying materials. The computed results showed that the flow structures of the carrier gas were very different for different gas and different spraying distance, which resulted in consequently different accelerating features. The cone-shape weak shocks (compression waves) occurred at the exit of divergent section, and the bow-shaped strong shock wave was found right before the substrate, which played a resistance role to the particles and prevented the smaller particles from approaching on the substrate. Copyright & 2005 by ASME.
AB - In this paper, numerical simulations were performed for the gas-particle two phase flow in the cold gas dynamic spray process to investigate the acceleration of micro- and nano-particles with diameters ranging from 100nm to 50μm, Nitrogen (N2) and Helium (He) were chosen as the carrier gas, respectively. The acceleration of carrier gas to particles in the De-Laval-Type supersonic nozzle was strongly dependent on the characteristics of flow field, as well as the densities and the size of the particles. Two kind of particles Copper (Cu) and Platinum (Pt) were chosen as the spraying materials. The computed results showed that the flow structures of the carrier gas were very different for different gas and different spraying distance, which resulted in consequently different accelerating features. The cone-shape weak shocks (compression waves) occurred at the exit of divergent section, and the bow-shaped strong shock wave was found right before the substrate, which played a resistance role to the particles and prevented the smaller particles from approaching on the substrate. Copyright & 2005 by ASME.
KW - Cold gas dynamic spray
KW - Gas-particle two phase flow
KW - Numerical modeling
KW - Supersonic flow
UR - http://www.scopus.com/inward/record.url?scp=29644432033&partnerID=8YFLogxK
U2 - 10.1115/HT2005-72372
DO - 10.1115/HT2005-72372
M3 - Conference contribution
AN - SCOPUS:29644432033
SN - 0791847314
SN - 9780791847312
T3 - Proceedings of the ASME Summer Heat Transfer Conference
SP - 145
EP - 150
BT - Proceedings of the ASME Summer Heat Transfer Conference, HT 2005
T2 - 2005 ASME Summer Heat Transfer Conference, HT 2005
Y2 - 17 July 2005 through 22 July 2005
ER -