• Journal of Aerospace System Engineering
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• v.9 no.4
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• pp.67-72
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• 2015

The analysis has been performed on the blockage effect at the propellant flow passage in a liquid rocket engine. This simulates an example of emergency situation where flow passage is partially blocked. The analysis method has been validated by predicting the pump head and flow rate within 1% precision against the measured data of turbopump-gas generator coupled test. When the oxidizer passage is reduced it is predicted that the mixture ratio decreases, the oxidizer pump head increases and the gas generator pressure increases. When the fuel passage is reduced it is predicted that the mixture ratio increases, fuel flow rate decreases and the fuel pump head increases.

• Journal of computational fluids engineering
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• v.8 no.3
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• pp.56-65
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• 2003

A numerical procedure for analyzing the heat transfer in a regenerative cooling passage of liquid rocket has been developed. The thermal analysis is based on the numerical model of Naraghi〔1〕. The thermodynamic and transport properties of the combustion gases are evaluated using the chemical equilibrium composition. The pressure and heat flux obtained by the isentropic relation are in good agreement with the result of Navier-Stokes equations. The effect of design parameters on heat transfer is addressed for the pressure loss and temperature variation. Also, their constraints in designing the cooling passage are recommended. Finally, in a heated rectangular duct, the effects of secondary flow on heat transfer are scrutinized by the nonlinear k- e -fu of Park et at.〔2〕.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.2
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• pp.137-141
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• 1991

Rumen liquor characteristics and disappearance rate of dry matter were studied in Kedah-Kelantan cattle and swamp buffaloes fed grass of rice straw-based diet. Cobalt-EDTA and chromium mordented fibres prepared from the faecal material were used to determine the liquid and solid particles movement in both animal species fed with rice straw. Swamp buffaloes showed a more intense rumen fermentation activity than Kedah-Kelantan cattle when both species were fed straw-based diet. The buffaloes also demonstrated faster rates of grass and straw degradation in situ. The fluid outflow rate from the rumen of buffalo ($1.06{\pm}0.19l/h$) was observed to be slower than that of cattle ($1.55{\pm}0.01l/h$). No significant differences between cattle and buffaloes were observed in rumen fluid volume and passage rate of small particles from the rumen.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.291.2-292
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• 2003

The purpose of this study was to investigate the transport characteristics of passage cultured l1uman nasal epithelial cell monolayers grown on Transwell@ inserts using liquid-covered culture (LCC) method. The monolayer of passage 2 and 3 exhibited tight barrier (TEER>1,000 ohmxcm$^2$) in 2-3 days after seeding. In the morphological studies by actin staining and SEM/TEM, the existence of tight junction was clearly observed. (omitted)

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1068-1072
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• 1998

We present results of molecular dynamic (MD) simulations for the segmental motion of liquid n-butane as the base case for a consistent study for conformational transition from one rotational isomeric state to another in long chains of liquid n-alkanes. The behavior of the hazard plots for n-butane obtained from our MD simulations are compared with that for n-butane of Brownian dynamics study. The MD results for the conformational transition of n-butane by a Poisson process form the total first passage times are different from those from the separate t-g and g-t first passage times. This poor agreement is probably due to the failure of the detailed balance between the fractions of trans and gauche. The enhancement of the transitions t-g and g-t at short time regions are also discussed.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1506-1511
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• 2003

The present study proposes a new structure for a flat plate heat pipe which could embody a thin thickness, any shapes and high heat density a unit area. It is on the structure for the formation of vapor passages and the support of the case of the flat plate heat pipe. A screen mesh is used as the one. To verify the validity of the one, the flat plate heat pipe of 1.08mm thickness was made with a layer of the screen mesh with 14 and 100 mesh number respectively and tested. Here the screen mesh with 14 mesh number plays a role of the vapor passage and the support of the case and the screen mesh with 100 mesh number functions as the wick structure. T he results show that the screen mesh excellently carries out the function of the vapor passage and the support of the case.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.36-41
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• 2001

In order to simulate wake of stator and a gas turbine engine's balde row, acryl cylinder and a linear turbine cascade were used respectively in this study. Experimental of heat transfer distributions was done on the passage endwall and blade suction surface. Temperature distributions on the experimental regions were obtained through image processing system by using the cholesteric type liquid crystal which has chain structure of metyl$(CH_3)$. To represent the degree of heat transfer, dimensionless St number was used. The results show that heat transfer on the blade suction surface was increased due to the wake from the cylinder and was decreased as the distance between cylinder row and blade row increases. Because of groth of passage vortex, heat transfer distributions on the trailing edge area showed triangular shape which was little changed with wake. On the other hand, heat transfer on the passage endwall was decreased due to the wake from cylinder. As the distance between cylinder row and blade row increases, heat transfer was more decreased.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.169-174
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• 2008

The growth characteristics of Paecilomyces tenuipes according to the passage in the two kind of liquid media were investigated by comparing the mycelium and conidium formation degrees. The potato dextrose broth medium and the silkworm larvae medium containing the silkworm powder were used as the liquid media, and the potato dextrose agar medium and the brown rice medium containing the powder of silkworm pupa were used as the solid media. The conidium formation degree in liquid media differed by the passages but that in solid media was not. This suggested that the passage in liquid media did not affect significantly the conidium formation in solid media. When the brown rice media were inoculated with the concentration of $1{\times}10^{10}$ conidia/ml, $1{\times}10^8$ conidia/ml and $1{\times}10^6$ conidia/ml, respectively, the conidium formation degrees were similar. This indicated that the optimal inoculation concentration of conidium to the brown rice media is $1{\times}10^6$ conidia/ml.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2386-2398
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• 1995

The paper describes the results of an experimental investigation of the heat transfer rate on the endwall surface within the plane turbine cascade passage and includes the effect of the heat transfer for the two different boundary layer thicknesses and Reynolds numbers. The limiting streamlines on the endwall surface have been visualized by the oil film method in order to compare with the endwall heat transfer. The hue-capturing method using the termochromatic liquid crystals with great spatial resolution has been used to provide the local distribution of the endwall heat transfer coefficients. Because the detailed contours of the local heat transfer coefficients over the entire endwall can be obtained from the hue-capturing method, it has been possible to obtain information on the endwall heat transfer within the plane turbine cascade passage from these heat transfer contours.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.76-81
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• 2003

To investigate the convective heat transfer phenomena inside the Lox/Kerosene liquid rocket combustion chamber, hot fire tests were performed by using a water-cooled calorimetric chamber. The calorimetric chamber consists of one cylindrical section and nozzle section with independent cooling passage. To measure the heat flux, thermocouples were installed inlet and outlet of cooling passage of each section. The investigated range of combustion chamber pressure is from 100 psi to 300psi at fixed O/F ratio of 2.0 and radiation heat transfer from the hot gas to the surface is not considered. The measured heat flux was almost linearly depended on the chamber pressure.