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A field test of a 70 ㎾ heat pump system with flue gas heat recovery was performed by an experiment at the Korea Institute of Energy Research. The flue gas is exhausted from a 320 RT absorption chiller-heater in the heating season. Using this flue gas, source water of the heat pump is heated by a condensed-type heat exchanger in the chimney. The operating characteristics of the heat recovery heat pump system were analyzed. Based on the results of the experiments, operating maps were obtained, and an optimum operating range is suggested, in which the return and heat source water temperature are 51℃ and 31℃, respectively. Additionally, economic analysis of this system was conducted and about 50% energy cost savings can be expected in the heating season. Key words Condensing heat recovery(응축열회수), Flue gas(배가스), Heat recovery system(열회수 시스템), Latentheat(잠열), Condensation(응축) †Corresponding author, E-mail: yslee@kier.re.kr (1, 2) 그러나 여전히 많은 에너지가 버려지 고 있으며, 배가스에 포함된 수증기의 응축잠열까지

A capillary pumped loop (CPL) which can be used for cooling electronic devices such as a CPU of a personal computer or note book was developed. An evaporator and a condenser with the same size of 30 mm × 30 mm × 1.55 mm were designed and fabricated using 3 layer of silicon wafer for the CPL. In the evaporator, 525 μm thickness silicon wafer where an array of 40 × 40 cone shaped micro holes were fabricated was inserted above the compensation cavity for liquid transportation instead of porous wick. The same cone shaped microstructure was used in the condenser to create a stable interface between the liquid and the vapor phases. The CPL fabricated was tested under various conditions such as different relative heights, fill ratios and heat fluxes. The operation conditions of CPL were varied depending on relative height and fill ratio. With an allowable temperature of 82 °C on the evaporator surfaces, the CPL can handle a heat flux of about 3.7 W/cm2 with the air cooled condenser. Steady state operation condition was achieved within 10 minutes.

This paper presents the process and experimental results about the improved initial bonding between #7740 glass and silicon wafers. We employed a modified initial bonding procedure, called by water-enhanced direct bonding(WDB) technique, and could obtain large initially-bonded area(≥ 95% of the whole wafer area) at room temperature and high interface energy (≥ 2,000 erg/cm2) through 250 °C post-annealing even though the glass wafer had high surface roughness. The main factors contributing to the wider bonded area and higher interface energy in the developed WDB process could be inferred the increase of chemical species (oxygen and hydroxyl groups) responsible for initial hydrogen bonding and conversion from hydroxyl bonds to siloxane bonds in the temperature range between room temperature and 250 °C.