• 드라이브 ㆍ 컨트롤
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• 제16권2호
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• pp.43-50
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• 2019

The objective of this study was to reverse engineer a swash plate type piston pump mounted on a wheeled armored vehicle and to analyze the structure of the pump case. From the analysis, the weak parts were identified and corrected in the final design. Each element corresponding to the piston pump case was analyzed. The analytical method was given static boundary conditions, load conditions and confirmed displacement, strain, stress, and safety factor. Plastic deformation and damage were also confirmed and the component elements redesigned through structural analysis Structural analysis and vibration analysis were carried out for the components of the piston pump case. The piston pump model was finally modified by structural analysis and vibration analysis results for each component assembly, and a prototype was designed. Durability test and environmental test were carried out and the test results satisfied all of the requirements. Therefore, the analytical method presented in this study can be utilized as a methodology for element component design in the development of various piston pumps.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.357-362
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• 2008

The present study has been conducted variable refrigerant flow system applied building. Multi air-conditioning system has some benefits : easier building management and maintenance and energy saving. Recently, the system heat pump has been employed in medium-sized and tall buildings. However, the performance data and design method for system heat pump are limited in literature due to complicated system parameters and operating conditions. In the present study, case study of a system heat pump applied various building. The aim of this paper is to application multi air-conditioners and to inform the benefits of multi air-conditioners.

• International Journal of Fluid Machinery and Systems
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• 제6권3호
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• pp.121-136
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• 2013

This paper reports the 1-D fluid transient simulation results of the discharge flow conditions in a 6-cylinder reciprocating slurry pump. Two discharge manifold configurations are studied comparatively; a case with a hexagon shaped discharge manifold where each cylinder discharges at a single vertex, and a case where all the cylinders discharges are lumped together into a tank shaped manifold. In addition, the study examines the effect of two pulsation mitigation measures in the case of hexagonal manifold; a single inline orifice in one of the hexagon sides and a volumetric dampener at the manifold outlet. The study establishes the pressure and flow fluctuation characteristics of each configuration and decouples the pulsation characteristics of the pump and the discharge manifold.

• 한국산학기술학회논문지
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• 제3권4호
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• pp.233-239
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• 2002

21세기에 가장 시급하게 확보되어야 하는 기술은 BT(Biotechonolgy)와 NT(Nano technology)를 접목시키는 기술이다. 특히, 이들을 종합한 MEMS 에 관한 연구는 가장 광범위한 분야에서 활발하게 이루어지고 있어 그 기술적 가치가 점차 중요시되고 있다. 본 연구는 Simulation을 통하여 Bio-MEMS 기술에서 사용되는 미세Pump 내에서의 유체흐름을 Fluent 프로그램을 사용하여 알아보고자 하였다. 즉, 미세Pump 내로 유체가 흐를 경우, 유체의 압력변화나 온도변화 및 Model에 따른 유동의 흐름을 관찰하여 미세Pump 내에서의 최적의 외부조건과 최적의 Pump Model을 알아보고자 실험하였다. 유동의 흐름을 조사해 본 결과 Chamber의 유무에 따라 압력과 온도의 변화를 관찰할 수 있었다. Chamber가 있는 경우 압력의 변화가 적었고 온도의 변화 또한 적었다. 따라서 Chamber가 있는 Pump가 유체의 흐름에 영향을 적게 줌을 알 수 있었으며 이는 Chamber가 있는 Pump를 설계하는 것이 필요하다고 할 수 있다.

• 동력기계공학회지
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• 제17권6호
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• pp.88-94
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• 2013

As the results of analysis that are applying a heat pump using underground water as heat source of facility horticulture house, temperature change in house, growth of cultivated plants and the crop characteristic, the conclusion can be acquired as follows. It was possible to maintain the chamber temperature through operating heat pump with setting goal temperature at $16^{\circ}C$ and temperature variation at ${\pm}3^{\circ}C$. And cooling and heating coefficient of performance in heat pump system are different from setting room temperature and operation condition of equipment, totally in case that the setting temperature in house is low, the coefficient of performance and the in case that temperature departure is low. In case that the house does not heated, the result of the growth characteristic of cucumber planted last 50days is that cucumber grown in house equipped with heat pump is the most favorable growth characteristic due to maintaining a constant room temperature. After 90 days, the quantity and weight cucumber harvested in each house are averagely 9.8%, 13.1% increase and more heavy weight respectively. So it is researched that crop characteristic is superior.

• 한국지열·수열에너지학회논문집
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• 제17권2호
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• pp.11-19
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• 2021

In this study, combined heat source heat pump system was implemented with 4 single heat source heat pumps each applied with a geothermal source and a water source. Five cases (Case1~Case5) were configured to conduct a performance comparison and analysis of the combined heat source heat pump system. First of all, as a result of analyzing the heat source, the case when 4 ground heat sources were applied (Case1) showed a uniform EST(Entering Source Temperature) distribution throughout the year since it is less affected by outside air compared to the case when 4 water heat sources were applied (Case5). In both winter and summer, the ground heat source maintained higher EST than the water heat source. Therefore, the system with high ratio of geothermal sources is advantageous for heating, and with high ratio of water heat sources is advantageous for cooling.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년도 춘계학술발표대회 논문집
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• pp.431-435
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• 2008

Geothermal heat pump system using standing column wells as their ground heat exchanger can be used as a highly efficient source of heating and cooling in massive buildings. But there is no case of a small scale residential house. So this study estimated heating coefficient of performance(COP) of geothermal heat pump system using standing column well type which is excellent in heat recovery in the residential house. As a result of analysis, The COP of heat pump is over average 6 and is excellent. And in consequence of making a comparative study according to the bleeding, the cop is higher in the case of bleeding. Therefore, bleeding affects the performance of the system. This study has shown performance result that stands on actual data. Therefore, this study provides ground data that needs when a low capacity of system designs for a residence with confidence elevation.

• 제어로봇시스템학회논문지
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• 제4권4호
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• pp.441-447
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• 1998

Motivated by a recent work, a fuzzy-power-controller(FPC) is designed for the relieving-horsepower control of output variable pump with electrical proportional valve and actually implemented on the industrial excavator. In order to calculate the output power of pump with input of FPC, a linear discrete time model of load system to pump is obtained and the result is applied to control the engine-pump coupled system by software without pressure and flow sensor. The FPC controls the engine and pump coupled system by relieving horsepower control according to the change of load and the running conditions in relieving horsepower control are selected by fuzzy inference engine. A case study is peformed through the construction of the control device and installation on the excavator. It shows that the relieving-horsepower control system with the FPC, as suggested in this paper, is superior to the conventional PID controllers. And also, the excavator, with the FPC, shows that the power-loss of the coupled system is reduced and the running speed of the hydraulic actuator is enhanced.

• 드라이브 ㆍ 컨트롤
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• 제15권4호
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• pp.23-29
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• 2018

The objective of this paper is to evaluate the reliability of a volute pump and presents test results through performance and life tests. The performance and life test methods were presented by analyzing the failure modes of the volute pump. Zero failure test time was calculated to evaluate the reliability of the volute pump and then, the test was performed under accelerated conditions. The test was also carried out to check the failure modes of the field conditions. This study can be provided to improve the product reliability through failure analysis of the volute pump. And failure cause of typical failure case has been investigated and improvement design has been presented. The performance test results of before and after the accelerated life test were presented to confirm the improved reliability of the volute pump.

• 한국지열·수열에너지학회논문집
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• 제17권4호
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• pp.59-67
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• 2021

In this study, the performance of the single heat source system and the hybrid system was comparatively analyzed. Case 1 is a ground heat source system, and Case 2 is a water heat source system. Case 3, a hybrid system, reduced the capacity of the ground heat source and applied a water heat source as an auxiliary heat source, and Case 4 was composed of a system that applied a water heat source as an auxiliary heat source to the ground heat source system. As a result of the simulation, in case 3, energy consumption was reduced by up to 2.67% compared to ground sources for cooling. In Case 4, COP was improved by up to 10.02% compared to ground sources during cooling, and EST was calculated to be 2.42℃ lower. During heating, 0.83% was improved compared to the water heat source. At this time, the EST was calculated to be 2.25℃ higher than the water heat source.