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Evaporation Pressure Drop Characteristics with R-22 in the Plate and Shell Heat Exchangers

  • Park, Jae-Hong;Seo, Moo-Gyo;Lee, Ki-Baik;Kim, Young-Soo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.10 no.3
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    • pp.129-137
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    • 2002
  • In this study, evaporation pressure drop experiments were conducted with two types of plate and shell heat exchangers (P&SHE) using R-22. An experimental refrigerant loop has been established to measure the evaporation pressure drop of R-22 in a vertical P&SHE. The flow channels were formed by stacking three plates having a corrugated channel of a chevron angle of 45 dog. The R-22 flows down in one channel exchanging heat with the hot water flowing up in the other channel. The effect of the refrigerant mass flux, average heat flux, system pressure and vapor quality were explored in detail. During the experiment, the quality change between the inlet and outlet of the refrigerant channel ranges from 0.03 to 0.15. The present data showed that two types of P&SHE have similar trends. The pressure drop in-creases with the vapor quality for both types of P&SHE. At a higher mass flux, the Pressure drop is higher for the entire range of the vapor quality. Also, the increase in the average heat flux increases the pressure drop. Finally, at a higher system pressure, the pressure drop is found to be slightly lower compared to the lower system pressure.

Experimental Study on R-410A Evaporation Heat Transfer Characteristics in Shell and Plate Heat Exchanger (셀 앤 플레이트 열 교환기에서의 R-410A 증발열전달에 관한 실험적 연구)

  • Kim In-Kwan;Kim Young-Soo;Park Jae-Hong
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.1
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    • pp.49-59
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    • 2005
  • The evaporation heat transfer experiments are conducted with the shell and plate heat exchanger (S&PHE) without oil in the refrigerant loop using R-410A. An experimental refrigerant loop has been established to measure the evaporation heat transfer coefficient h. of R-410A in a vertical S&PHE. Two vertical counter flow channels were formed in the S&PHE by three plates haying a corrugated trapezoid shape of a $45^{\circ}C$ chevron angle. UP flow of the boiling R-410A in one channel receives heat from the hot down flow of water in the other channel The effects of the refrigerant mass flux. average heat flux. refrigerant saturation temperature and vapor qualify are explored in detail. Similar to the case of a plate heat exchanger. even at a very low Reynolds number, the flow in the S&PHE remains turbulent. The Present data shows that the evaporation heat transfer coefficients of R-410A increased with the vapor qualify. The results indicate a rise in the refrigerant mass flux caused an increase in the h.. Raising the imposed wall heat flux is found to slightly improve h., while h, is found to be lower at a higher refrigerant saturation temperature. Based on the present data. empirical correlation of the evaporation heat transfer coefficient is proposed.

An Experimental Study on Steering Performance of Seafloor Tracked Vehicle Based on Design Of Experiment Using Orthogonal Array (직교행렬 실험계획법에 의한 해저연약지반 선회성능실험 연구)

  • Choi, Jong-Su;Hong, Sup;Kim, Hyung-Woo
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.10a
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    • pp.250-253
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    • 2003
  • This paper concerns about an experimental investigation about steering performance of tracked vehicle on extremely soft soil based on DOE(Design Of Experiment) using L8 orthogonal Array. A tracked vehicle model with principal dimensions of $0.9m{\times}0.8m{\times}0.4m$ and weight 167kg was constructed with a pair of driving chain links driven by two AC-servo motors. The tracks are configured with detachable grousers, the span of which can be varied. Deep seabed was simulated by means of bentonite-water mixture in a soil bin of $6.0m{\times}3.7m{\times}0.7m$. Turning radii of vehicle and torques of motors were measured with respect to experimental variables; steering ratio, driving speed, grouser chevron angle, grouser span, grouser height. The effects of experiment variables on steering performance are evaluated.

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Experimental Study on R-l34a Condensation Beat Transfer Characteristics in Plate and Shell Heat Exchanger (판각형 열교환기내의 R-134a 응축열전달 특성에 관한 실험적 연구)

  • 이기백;박재홍;서무교;이희웅;김영수
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.1
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    • pp.108-116
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    • 2003
  • In this paper, the experimental results of condensation heat transfer were reported for the plate and shell heat exchangers(P&SHE) using R-l34a. An experimental refrigerant loop has been established to measure the condensation heat transfer coefficient of R-l34a in a vertical P&SHE. Two vertical counter flow channels were formed in the P&SHE by three plates of geometry with a corrugated trapezoid shape of a chevron angle of 45$^{\circ}$. Downflow of the condensing R-l34a in one channel releases heat to the cold up flow of water in the other channel. The effect of the refrigerant mass flux, average heat flux, system pressure and vapor quality of R-l34a on the measured data were explored in detail. The results indicate that at a higher vapor quality the condensation heat transfer coefficients are significantly higher. Condensation heat transfer coefficients were increased when the refrigerant mass flux was increased. A rise in the average heat flux causes an slight increase in the hr. Finally, at a higher system pressure the hr is found to be lower. Correlation is also provided for the measured heat transfer coefficients in terms of the Nusselt number.

An Experimental Study about Tractive Performance of Tracked Vehicle on Deep-sea Soft Sediment Based on Design of Experiment Using Orthogonal Array (직교배열표 실험계획법에 의한 심해 연약지반용 무한궤도차량의 견인성능에 대한 실험적 연구)

  • Choi, Jong-Su;Hong, Sup;Kim, Hyung-Woo;Lee, Tae-Hee
    • Ocean and Polar Research
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    • v.26 no.2
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    • pp.333-339
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    • 2004
  • This paper is concerned with an experimental investigation about tractive performance of a tracked vehicle on extremely soft soil. A tracked vehicle model with principal dimensions of $0.9\;m(L)\;{\times}\;0.75\;m(B)\;{\times}\;0.4\;m(H)$ and the weight of 167 kg was constructed with a pair of driving chain links driven by two AC-servo motors. The tracks are configured with detachable grousers with variable span. Deep seabed was simulated by means of bentonite-water mixture in a soil bin of $6.0\;m(L)\;{\times}\;3.7\;m(B)\;{\times}\;0.7\;m(H)$. Slip of vehicle and driving torque of motor were measured with respect to experimental variables; grouser span, grouser chevron angle, driving speed, drawbar-pull weight, position of center-of-gravity and weight. $L_8$ orthogonal array is adopted for DOE (Design Of Experiment). The effects of experiment variables on traction performance are evaluated.

A Numerical Study on the Performance of Plastic Coated Aluminium Plate Heat Exchanger (플라스틱 코팅 알루미늄 판형 열교환기의 성능에 관한 수치해석적 연구)

  • Choi, Geun-Ho;Kim, Young Il;Kim, Myoung-Soo
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.14 no.1
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    • pp.22-29
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    • 2018
  • The purpose of this study is to investigate the preliminary thermal performance of a plastic coated aluminum material(PCAM) plate heat exchanger. Plastic coating which has high corrosion resistivity and thermal conductivity can overcome corrosive weakness of aluminum material. The heat exchangers are modeled for STS316, Titanium and PCAM materials, and analyzed numerically using HTRI and ANSYS Fluent CFD softwares. The results show that PCAM heat exchanger is superior in heat transfer performance compared to existing materials. For chevron angle of $60^{\circ}$, thermal performances of Titanium and PCAM are higher by 12.2% and 48.9% when compared to STS316, respectively.

Experimental Study on R-22 Condensation Heat Transfer Characteristic in Plate and Shell Heat Exchanger (Plate and Shell 열교환기 내의 R-22 응축열전달 특성에 관한 실험적 연구)

  • Seo, Mu-Gyo;Park, Jae-Hong;Kim, Yeong-Su
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.6
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    • pp.860-867
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    • 2001
  • In this study, condensation heat transfer experiments were conducted with plate and shell heat exchangers(P&SHE) using R-22. An experimental refrigerant loop has been established to measure the condensation heat transfer coefficient of R-22 in a vertical P&SHE. Two vertical counter flow channels were formed in the P&SHE by three plates of geometry with a corrugated trapezoid shape of a chevron angle of 45°. Downflow of the condensing R-22 in one channel releases heat to the cold upflow of water in the other channel. The effect of the refrigerant mass flux, average heat flux, system pressure and vapor quality of R-22 on the measured data were explored in detail. The results indicate that at a higher vapor quality the condensation heat transfer coefficients are significantly higher. A rise in the refrigerant mass flux causes an increase in the h(sub)r. Also, a rise in the average heat flux causes an increase in the h(sub)r. Finally, at a higher system pressure the h(sub)r is found to be slightly lower. Correlation is also provided for the measured heat transfer coefficients in terms of the Nusselt number.

A Study on the Performance Analysis in the Plate and Shell Heat Exchanger (판각형 열교환기 성능해석에 관한 연구)

  • Seo, M.K.;Park, J.H.;Kim, Y.S.
    • Journal of Power System Engineering
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    • v.5 no.1
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    • pp.35-43
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    • 2001
  • Heat exchangers are called with important devices which have been widely used in industrial fields. Therefore, the design method for a heat exchanger is an important study in the aspect of energy saving. In this study, performance analyses for two types of plate and shell heat exchangers having a corrugated trapezoid shape of a chevron angle with $45^{\circ}$, were executed and compared with experiments. For this study, the operation liquids were adopted with non-phase changing water. In the analysis, ${\epsilon}-NTU$ method was used for a plate and shell heat exchanger and a program was constructed. Independent variables for a plate and shell heat exchanger are flow rate and inlet temperature. Compared with experimental data, the accuracy of the developed are ${\pm}2.5%\;and\;{\pm}5%$ at the type A and type B in the heat transfer rate, respectively. In the pressure drop, the accuracy of the proposed program for a plate and shell heat exchanger is within ${\pm}3%$ and 5% error bounds for the type A and type B, respectively.

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판각형 열교환기 내의 R-22 증발 압력강하 특성에 관한 실험적 연구

  • 서무교;박재홍;김영수
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.10
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    • pp.930-938
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    • 2001
  • In this study, evaporation pressure drop experiments were conducted with two types of plate and shell heat exchangers (P&SHE) using R-22. An experimental refrigerant loop has been established to measure the evaporation pressure drop of R-22 in a vertical P&SHE. The flow channels were formed by adding three plates having a corrugated channel of a chevron angle of $45^{\circ}$. The R-22 flows down in one channel exchanging heat with the hot water flowing up in the other channel. The effect of the refrigerant mass flux, average heat flux, system pressure and vapor quality were explored in detail. During the experiment, the quality change between the inlet and outlet of the refrigerant channel ranges from 0.03 to 0.15. The present data showed that two types of P&SHE have similar trends. The pressure drop increases with the vapor quality for both types of P&SHE. At a higher mass flux, the pressure drop is higher for the entire range of the vapor quality. Also, the increase in the average heat flux increases the pressure drop. Finally, at a higher system pressure, the pressure drop is found to be slightly lower.

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The Fouling Characteristics of Plate Heat Exchangers with Geometric and Operating Parameters (판형열교환기의 운전 및 설계변수에 따른 파울링 특성에 관한 연구)

  • Jeon, Jaemyeong;Lee, Eungchan;Kang, Hoon;Kim, Yongchan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.4
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    • pp.163-168
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    • 2014
  • The plate heat exchanger has been widely used in water heating systems due to high efficiency, simple structure, and easy maintenance. However, the studies on the effects of fouling on the heat transfer performance under various operation and maintenance conditions are very limited in the open literature. The objective of this study is to investigate the effects of fouling with calcium carbonate ($CaCO_3$) on the heat transfer characteristics of the plate heat exchanger under various operating and geometric conditions. The heat transfer coefficient and pressure drop in the plate heat exchangers were measured under accelerated fouling conditions with $CaCO_3$ by varying geometric and operational parameters. The fouling resistance increased with the decrease in the flow rate, and the increase in the chevron angle and the concentration.