• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.12-17
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• 2014

The cooling of precooked skipjack Katsuwonus pelamis is a critical thermal process in tuna canning because it affects the quality and yield of the canned tuna, as well as productivity. The combined method of vacuum cooling followed by water spraying (VC-WS) was investigated to increase cooling rates, and prevent loss of yield of the precooked tuna during vacuum cooling. For VC-WS, the precooked skipjack was cooled to $30^{\circ}C$ by vacuum at 31 mmHg and then wetted by spraying water for 2 min. The effects of VC-WS on cooling times, cooling loss, color, texture and lipid oxidation of the precooked tuna were compared with conventional spray cooling (SC).The cooling times for precooked skipjack from $75^{\circ}C-30^{\circ}C$ were 11 min for VC-WS and 145 min for SC. The cooling losses were 1.7 % for VC-WS and 1.6 % for SC. Peroxide and thiobarbituric acid (TBA) values of VC-WS were lower than those of SC. The loin of the VC-WS-treated skipjack was brighter and harder than the SC loin, as indicated by higher lightness and hardness values. Based on these results, we believe that the VC-WS process could compensate for the cooling loss of vacuum cooling and minimize changes in quality that occur during cooling of precooked skipjack tuna.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.403-408
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• 2001

In order to control hydration heat in mass concrete, pipe cooling method has been widely used. However, open pipe cooling system cannot be applied to the mass concrete structures when cooling water supply is difficult. To control hydration heat of high strength mass foundation, closed loop pipe cooling system was developed to solve the cooling water supply. This paper reports the performance result of hydration heat control with closed loop pipe cooling system.

• Plant Journal
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• v.13 no.4
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• pp.38-40
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• 2017

This study is for stabilization of the water balance of the closed cooling water system. The pipe network analysis program is used for the water balance review, and the resistance factor correction is performed through the field measurement with the ultrasonic flowmeter to improve the reliability of the pipe network software. Based on this, it is aimed to derive optimal driving method through various case simulations.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.233-238
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• 2006

A new district cooling system using ice slurry for the uncertain cooling load of the future is presented. The chilled water produced by the absorption chillers is used for the base cooling load. The temperature of the chilled water is reduced by mixing of ice slurry depending on increasing of the cooling load. Finally, IPF of the ice slurry is increased up to 10% at the peak load. The transporting mass flow rate is decreased down to 44.7%, and the diameter of the main pipe is decreased down to 66.7%, but the diameter of the branched pipe is designed as the same size of the chilled water.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.5
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• pp.503-511
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• 2011

Water spray cooling is a significant technology for cooling of materials from high-temperature up to $900^{\circ}C$. The effects of cooling water temperature on spray cooling are mainly provided for hot steel plate cooling applications in this study. The heat flux measurements are introduced by a novel experimental technique that has a function of heat flux gauge in which test block assemblies are used to measure the heat flux distribution on the surface. The spray is produced by a fullcone nozzle and experiments are performed at fixed water impact density of G and fixed nozzle-totarget spacing. The results show that effects of water temperature on forced boiling heat transfer characteristics are presented for five different water temperatures between 5 to $45^{\circ}C$. The local heat flux curves and heat transfer coefficients are also provided to a benchmark data for the actual spray cooling of hot steel plate cooling applications.

• Membrane and Water Treatment
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• v.8 no.4
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• pp.355-367
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• 2017

In India, the current operation of condenser cooling system & effluent disposal system in existing power plants aims to reduce drawal of seawater and to achieve Zero Liquid Discharge to meet the demands of statutory requirements, water scarcity and ecological system. Particularly in the Steam-Electric power plants, condenser cooling system adopts Once through cooling (OTC) system which requires more drawal of seawater and effluent disposal system adopts sea outfall system which discharges hot water into sea. This paper presents an overview of closed-loop technology for condenser cooling system and to achieve Zero Liquid Discharge plant in Steam-Electric power plants making it lesser drawal of seawater and complete elimination of hot water discharges into sea. The closed-loop technology for condenser cooling system reduces the drawal of seawater by 92% and Zero Liquid Discharge plant eliminates the hot water discharges into sea by 100%. Further, the proposed modification generates revenue out of selling potable water and ZLD free flowing solids at INR 81,97,20,000 per annum (considering INR 60/Cu.m, 330 days/year and 90% availability) and INR 23,760 per annum (considering INR 100/Ton, 330 days/year and 90% availability) respectively. This proposed modification costs INR 870,00,00,000 with payback period of less than 11 years. The conventional technology can be replaced with this proposed technique in the existing and upcoming power plants.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2907-2912
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• 2007

The cooling water system for the PEFP 20 MeV proton accelerator was established and tested to obtain the precise resonance frequency of DTL through the temperature control of cooling water. The water temperature in the main flow loop was manipulated by adjusting the proportion of hot water returning from the DTL structures through the heat exchanger loop. Due to low duty factor operation and insufficient cooling loop installation of the DTL tanks, the manual mode operation was applied to maintain the DTL temperatures close to their resonance temperatures. The optimized process conditions with flow balancing and pressure drop in the DTL cooling systems are reported.

• Journal of Energy Engineering
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• v.21 no.3
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• pp.221-227
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• 2012

The CANDU 9 shield cooling system was designed and layout with the objective of promoting natural circulation on loss of forced flow. In the present study, the shield cooling natural circulation was analyzed using verified the thermal-hydraulic code when the coolant pump or the heat exchanger was lost. This study showed that thermosyphoning cooled the end shields and prevented the end shields and the reserve water tank from boiling for at least 8 hours on loss of the shield cooling pumps but the heat exchangers still operational. With the loss of both pumps and heat exchangers, the end shields remain subcooled for up to 4 hours. To enhance thermosyphoning, the bypass connection to the line from the reserve water tank should be relocated to a point as low as possible.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.16 no.3
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• pp.295-304
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• 1987

The purpose of this study is to develop a computer model for simulating the water-lit hium bromide absorption heat transformer (AHT) Including all major components and to find the flexibility in operation. The effect of source hot water temperature, cooling water temperature, useful hot water flow rate, cooling water flow rate and evaporator circulation flow rate were investigated. The coefficient of performance (COP), temperature boost $({\Delta}T\;=\;T_A\;-\;Ti)$ and concentration variations can be predicted. The performance study indicates that the performance of AHT increases for the waste hot water temperature increasing and with a decrease of the cooling water temperature. The effect on performances of useful hot water flow rape is significant except on temperature boost. Also the effects on performance of cooling water flow rate and evaporator circulation flow rate are small. It is shown that the computer program is valuable to predict the performance of absorp-tion heat transformer units at various working corditions.

• Agricultural and Biosystems Engineering
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• v.6 no.1
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• pp.27-33
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• 2005

Soy protein meat analog was produced using a twin-screw extruder attached with a cooling die. Heat transfer analysis was performed for cooling dies with various die sizes at the four different moisture contents of feed during extrusion process. The experimental design consisted of two cooling die widths (30 and 60 mm), three cooling die lengths (100, 200, and 300 mm), four product moisture contents (71.2, 67.0, 61.6 and 55.8%), and water and water plus ethylene glycol as cooling material. When water was used as cooling medium, the values of equivalent overall heat transfer coefficient $(U_e)$ for each die width of 30 and 60 mm were in the range of 187.0 - 341.4 and $358.5-191.6W/m^2^{\circ}C$ depending on the size of die length. Convective heat transfer coefficients between cooling water and inside die wall of cooling channel $(h_c)$ for both die widths of 30 and 60 mm were 588.5, 416.1, and $339.8W/m^2^{\circ}C$ for each die length of 100, 200, and 300 mm. Convective heat transfer coefficients between product and inside die wall of product channel $(h_p)$ for each die width of 30 and 60 mm were in the range of $434.6-888.1W/m^2^{\circ}C$ and $460.7-1014.5W/m^2^{\circ}C$ depending on the size of die length. When water plus ethylene glycol was used as cooling medium, the values of $U_e$ were in the range of $143.9-319.6W/m^2^{\circ}C$ and $177.8-332.7W/m^2^{\circ}C$ for each die width of 30 and 60 mm depending on the size of die length.