• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.573-576
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• 1995

The realization by many industrial countries that manufacturing is a critical ingredient for attaining economic strength and stability has led to the development of automated systems which were proviously considered as gimmicks. The adaptive skill of the human operator is now being simulated and reproduced by computer that have become more powerful and less expensive. The work presented in this paper forms an investigation of the effects of dynamic viscosity and load of hydraulic oil an pressures with three different circuit(meter-in, meter-out and bleed off). The experimental results showed that pressures increase with an increase in dynamic viscosity and load in bleed off circuit, but there is no variation of pressure in meter-In meter-out circuit.

• 대한기계학회논문집
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• 제18권5호
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• pp.1218-1226
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• 1994

The shock tube is a useful device for investigating shock phenomena, spray combustion, unsteady gas dynamics, etc. Therefore, it is necessary to analyze exactly the flow phenomena in shock tube. In this study, the mechanics of its reflected shock zone has been investigated by using of the one-dimensional gas dynamic theory in order to estimate the transition from initial reflection of shock wave region. Calulation for four kinds of reflected shock tube temperature (i.e. (a) 1388 K (b) 1276 K (c) 1168 K (d) 1073 K) corresponding to the experimental conditions have been carried out sumarized as follows. (1) The qualitative tendency is almost the same as in that conditions in region of reflected wave region. (2) High temperature period (reflected shock wave temperature) $T_{5}$, exists 0-2.65 ms. (3) Transition period from temperature of reflection shock wave is far longer than the calculated one. This principally attributed to the fact that the contact surface is accelerated, also, due to the release of energy by viscoity effect. This apparatus can advance the ignition process of a spray in a ideal condition that involved neither atomization nor turbulent mixing process, where, using a shock tube, a column of droplets freely from atomizer was ignited behind a reflected shock.