• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집E
• /
• pp.499-505
• /
• 2001

The objective of the paper was to measure the pressure drop and to investigate the recirculation region of the conical orifices used in Kwang-yang Iron & Steel Company. The flow field with water used as a working fluid was the turbulent flow for Reynolds number of $2{\times}10^4$. The effective parameters for the pressure drop and the recirculation region were the conical orifice's inclined angle (${\theta}$) against the wall, the interval(L) between orifices, the relative angle of rotation(${\alpha}$) of the orifices, the shape of the orifice's hole(circle, rectangle, triangle) having the same area. It was found that the shape of the orifice's hole affected the pressure drop and the flow field a lot, But the other parameters did not make much differences to the pressure drop. The PISO algorithm with FLUENT code was employed.

• 대한기계학회논문집B
• /
• 제21권10호
• /
• pp.1371-1379
• /
• 1997

The high pressure drop is frequently required in the by-pass line of the pump or of the heat exchanger in power plants. However, cavitation produced by a high pressure drop could damage the pipe and pump blades. Conical orifices are adopted to reduce cavitation due to high pressure drop. The discharge coefficients of conical orifice plates were measured by weighing method in the standard water flow system. The discharge coefficients were larger when the ratios of thickness of orifice edge to throat diameter were larger. The noise generated from a conical orifice due to cavitation was measured with a sound level meter and a hydrophone. With increasing the bore diameter of the orifice, the sound pressure level or the noise level due to cavitation became higher. The noise level was suddenly increased at the inception of cavitation.

• 대한기계학회논문집B
• /
• 제26권2호
• /
• pp.278-287
• /
• 2002

The objective of the paper was to calculate the pressure drop and to investigate the recirculation region of the conical orifices used in Kwang-yang Iron & Steel Company. The flow field with water used as a working fluid was the turbulent flow for Reynolds number of 2$\times$10$^4$. The effective parameters fur the pressure drop and the recirculation region were the conical orifice\`s inclined angle ($\theta$) against the wall, the interval(S) between orifices, the relative angle of rotation($\alpha$) of the orifices, the shape of the orifice's hole(circle, rectangle, triangle) having the same area, the number(N) of the orifice's holes having the same mass flow rate, and the thickness(t) of the orifices. It was fecund that the shape of the orifice's hole, the number of the orifice's holes and the thickness of the orifice affected the total pressure drop a lot and that the conical orifice's inclined angle against the wall, the relative angle of rotation of the orifices, the number of the orifice's holes and the thickness of the orifices affected the center location of the recirculation region. The PISO algorithm with FLUENT code was employed to analyze the flow field.