In the water jet looms, the distribution of the speed of water jet at the axis of the shed and its regularity are obtained by the Laser Doppler Tester. Based on the above, the water jet system is analyzed and the main...In the water jet looms, the distribution of the speed of water jet at the axis of the shed and its regularity are obtained by the Laser Doppler Tester. Based on the above, the water jet system is analyzed and the main effective approaches to increase the filling insertion rate and to widen the reed space of the loom are pointed out.展开更多
The thermal resistances distribution in different wet-bulb temperatures, air velocities and spraying water densities were achieved by the experimental test. The fluctuation of the water film convection and the water-a...The thermal resistances distribution in different wet-bulb temperatures, air velocities and spraying water densities were achieved by the experimental test. The fluctuation of the water film convection and the water-air interfacial thermal resistance were reviewed especially. In the distribution of thermal resistance, the rank of the thermal resistance proportion （from max to min） is air flow heat transfer resistance, heat transfer resistance between refrigerant and wall, water film convection resistance and wall heat transfer resistance. When the heat flux is constant, the total resistance lowers nearly along with the increasing of air flow and water spray density. But there are a best air flow value of 2.98 m/s and a best spray water density of 0.064 kg/（m ·s） respectively, if continue to increase them, condensation performance is not significantly improved any more. The test results are available to improve the evaporative condenser performance and the designing lever.展开更多
The mixing phenomena of a two-layer density-stratified fluid induced by a jet in a tank are experimentally investigated. The upper and lower fluids are water and a NaCl-water solution, respectively, with the lower flu...The mixing phenomena of a two-layer density-stratified fluid induced by a jet in a tank are experimentally investigated. The upper and lower fluids are water and a NaCl-water solution, respectively, with the lower fluid issued vertically upward from a nozzle at the bottom of the tank. The jet Reynolds number Re, defined by the jet velocity and the water kinematic viscosity, ranges from 90 to 4,200. The mass concentration of the NaCl-water solution Co is less than 0.08. The flow visualization makes clear the jet behavior relative to the density interface between the upper and lower fluids. The measurement of the concentration distribution of the water paint issued with the jet highlights the effects of Re and Co on the mixing between the jet and the ambient fluid. The measurement of the fluid velocity distribution with a PIV （particle image velocimetry） system successfully elucidates the relationship between the velocity field and the resultant mixing.展开更多
文摘In the water jet looms, the distribution of the speed of water jet at the axis of the shed and its regularity are obtained by the Laser Doppler Tester. Based on the above, the water jet system is analyzed and the main effective approaches to increase the filling insertion rate and to widen the reed space of the loom are pointed out.
文摘The thermal resistances distribution in different wet-bulb temperatures, air velocities and spraying water densities were achieved by the experimental test. The fluctuation of the water film convection and the water-air interfacial thermal resistance were reviewed especially. In the distribution of thermal resistance, the rank of the thermal resistance proportion （from max to min） is air flow heat transfer resistance, heat transfer resistance between refrigerant and wall, water film convection resistance and wall heat transfer resistance. When the heat flux is constant, the total resistance lowers nearly along with the increasing of air flow and water spray density. But there are a best air flow value of 2.98 m/s and a best spray water density of 0.064 kg/（m ·s） respectively, if continue to increase them, condensation performance is not significantly improved any more. The test results are available to improve the evaporative condenser performance and the designing lever.
文摘The mixing phenomena of a two-layer density-stratified fluid induced by a jet in a tank are experimentally investigated. The upper and lower fluids are water and a NaCl-water solution, respectively, with the lower fluid issued vertically upward from a nozzle at the bottom of the tank. The jet Reynolds number Re, defined by the jet velocity and the water kinematic viscosity, ranges from 90 to 4,200. The mass concentration of the NaCl-water solution Co is less than 0.08. The flow visualization makes clear the jet behavior relative to the density interface between the upper and lower fluids. The measurement of the concentration distribution of the water paint issued with the jet highlights the effects of Re and Co on the mixing between the jet and the ambient fluid. The measurement of the fluid velocity distribution with a PIV （particle image velocimetry） system successfully elucidates the relationship between the velocity field and the resultant mixing.
