• Title/Summary/Keyword: Ultrasonic apparatus

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A Study on the Propriety of Ultrasonic Atomization Apparatus for the Gasoline Engine (l) - In the Case of the Atomization of Fual - (가솔린 기관용 초음파 미립화장치의 타당성에 관한 연구 (I) - 연료 미립화를 중심으로 -)

  • 조규상
    • Journal of the korean Society of Automotive Engineers
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    • v.9 no.4
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    • pp.41-49
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    • 1987
  • It is an experimental study to improve the characteristics of combustion and exhaust emission gas in the gasoline engine. These characteristics are influenced by the fuel droplet size. To improve these characteristics, we make the ultrasonic atomization apparatus, and compare with the commercial carburetor. The results obtained are as follows: 1. Maximum atomization quantity is obtained by the vibrator of resonancy frequency 1.65MHz in the ultrasonic atomization apparatus. 2. With ultrasonic atomization apparatus, more than 99% of atomization rate can be obtained regardless of intake air temperature, velocity, and air-fuel ratio. 3. Atomization rate of the commercial carburetor increases with the air-fuel ratio and intake air temperature. 4. Difference of atomization rate between the ultrasonic atomization apparatus and the commercial carburetor increases with decreasing air-fuel ratio. 5. Droplet size is about 1-5.mu.m at the ultrasonic atomization apparatus, and 80-150.mu.m at the commercial carburetor, which indicates the ultrasonic atomization apparatus is excellent in atomization.

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The Characteristics of Silica Powders Prepared by Spray Pyrolysis Applying Droplet Classification Apparatus (액적 분급 장치를 적용한 분무열분해 공정으로부터 합성된 실리카 분말의 특성)

  • Kang, Yun-Chan;Ju, Seo-Hee;Koo, Hye-Young;Kang, Hee-Sang;Park, Seung-Bin
    • Korean Journal of Materials Research
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    • v.16 no.10
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    • pp.633-638
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    • 2006
  • Silica powders with spherical shape and narrow size distribution were prepared by large-scale ultrasonic spray pyrolysis applying the droplet classification apparatus. On the other hand, silica powders prepared by large-scale ultrasonic spray pyrolysis without droplet classification apparatus had broad size distribution. Droplet classification apparatus used in this paper applied the principles of cyclone and dispersion plate with small holes. The droplets formed from the ultrasonic spray generator applying the droplet classification apparatus had narrow size distribution. The droplets with fine and large sizes were eliminated by droplet classification apparatus. The optimum flow rate of the carrier gas and diameter of the hole of the dispersion plate were studied to reduce the size distribution of the silica powders prepared by large-scale ultrasonic spray pyrolysis. The size distribution of the silica powders prepared by large-scale ultrasonic spray pyrolysis at the optimum preparation conditions was 0.76.

Extraction Methods and HPLC Analysis Conditions of Paeoniflorin in Peony, Paeonia lactiflora Pall. (작약(Paeonia lactiflora Pall.)에서 paeoniflorin 추출방법 및 HPLC 분석조건)

  • ;Kwang-He Kang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.6
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    • pp.542-547
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    • 1994
  • To find out the most reasonable analysis conditions of paeoniflorin, different paeoniflorin extraction methods and various UV detector wavelengths were conducted with paeonia radix of 4-year old Euisung local variety. The most reasonable paeoniflorin extraction time by reflux apparatus was 1hr. and by ultrasonic apparatus was 3hrs. and those methods were completed only once. Concentration of paeoniflorin by reflux apparatuses at 1hr. and 2hrs. of extracting time were higher than those of ultrasonic apparatus, and the differences were highly significant. However, the differences of paeoniflorin concentration at 3hrs. and 4hrs. in two methods were not significant. In comparing paeoniflorin concentration of many lines, ultrasonic extracting apparatus was more simple and effective than the reflux apparatus. Paeoniflorin was more reasonable sensitivity at 240nm, and albiflorin was 254nm by HPLC. When paeoniflorin and albiflorin were analyzed simultaneously, 254nm was more stable than any other wavelength.

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A Study on the Alkali Hydrolysis of PET fabric with Ultrasonic Application(I) - Decomposition Rate Constant and Activation Energy - (초음파를 적용한 PET 직물의 알칼리 가수분해에 관한 연구(I) - 분해속도상수와 활성화 에너지-)

  • 서말용;조호현;김삼수;전재우;이승구
    • Textile Coloration and Finishing
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    • v.14 no.4
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    • pp.214-222
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    • 2002
  • In order to give a silk-like touch to PET fabrics, the PET fabrics were treated with NaOH alkaline solution in various conditions. In alkaline treatment, the liquor flow type pilot weight reduction apparatus with magnetostrictive ultrasonic transducer was used for the study. The weight loss of PET fabrics hydrolyzed in 4% and 6% NaOH solution, at $95^\circ{C}$ and $99^\circ{C}$ for 60min. with ultrasonic application showed 3.7~4.6% higher than that of treated fabric without ultrasonic application. From the difference of specific weight loss, the treatment condition of the maximum of hydrolyzation effect appeared at $95^\circ{C}$ in $4^\circ{C}$ and at $90^\circ{C}$ in 6% NaOH solution, respectively. During the alkali hydrolysis of PET fabrics, the decomposition rate constant(k) increased exponentially with the treatment temperature and were not related with ultrasonic cavitation. The activation energy$(E_a)$ in decomposition of PET fabrics were 21.06kcal/mol with ultrasonic application and 21.10kcal/mol without ultrasonic application. The ultrasonic application gave a little higher value of the activation entropy$(\Delta{S}^\neq)$ and a little lower value of Gibbs free energy$(\Delta{S}^\neq)$ compared with not used ultrasonic apparatus.

Sludge Carbon Source Using Ultrasonic apparatus (초음파를 이용한 슬러지 탄소원)

  • 김영규;임영택
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2002.04a
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    • pp.29-30
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    • 2002
  • In this study, comparison the removal efficiencies of organics, nitrogens and phosphorus from sewage using Ultrasonic apparatus were investigated. The concentration of SCODcr were respectively 16.3, 24.4, 48.8, 105.7, 260.3 mg/$\ell$ with time 0, 10, 30, 60, 120min respectively in 200W ultrasonic intensity. The concentration of SCODcr were respectively 124.4, 48.8, 73.2, 203.4, 374.2 mg/$\ell$ with time 0, 10, 30, 60, 120min respectively in 300W ultrasonic intensity. The concentration of SCODcr were respectively 24.4, 40.7, 81.4, 170.9, 439.3 mg/$\ell$ with time 0, 10, 30, 60, 120min respectively in 400W ultrasonic intensity.

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A Study on Fabrication and Characteristics of PVDF Ultrasonic Transducer (PVDF 초음파 변환기의 제작과 특성에 관한 연구)

  • Jung, Hong-Ryang
    • Journal of radiological science and technology
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    • v.23 no.2
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    • pp.33-37
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    • 2000
  • The authors fabricated ultrasonic transducer with PVDF[poly(vinylidene fluoride)] piezoelectric polymer film. When impulse waves were applied to the PVDF ultrasonic transducer, the dependence of the response properties on the backing material with copper was investigated through not only theoretical calculations using Mason's equivalent circuit but also experimental measurements. The experimental pulse response properties agree with those of the theoretical calculations and the pulses were shorter than those for a PZT transducer. If such short-pulse properties are used in an medical ultrasonic image diagnosis apparatus, the resolution of the apparatus will be improved. When the insertion loss was calculated theoretically to the PVDF ultrasonic transducer, the frequency characteristics of its showed wideband frequency.

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Surface Flatness Improvement in Si Anisotropy Etching Process Utilizing Ultrasonic Wave Technology (초음파 기술을 이용한 실리콘 이방성 식각 공정에서의 표면 평탄화 향상 연구)

  • Yun, Eui-Jung;Kim, Jwa-Yeon;Lee, Kang-Won;Lee, Seok-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.416-417
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    • 2005
  • In this study, we optimized the process of Si anisotropy etching by combing tetramethyl ammonium hydroxide (TMAH) etching process with ultrasonic wave technology. New ultrasonic TMAH etching apparatus was developed and it was used for fabricating a $20{\mu}m$ thick diaphragm for Si piezoresistive pressure sensors. Based on comparison study on etch rate and surface flatness, it was observed that the Si anisotropy etching methode with new ultrasonic TMAH etching apparatus (at 40 kHz/ 500 watt) was superior to conventional etching methods with TMAH or TMAH+ammonium persulfate(AP) solutions.

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Assemblage and Driving Characteristics of a Ultrasonic Fabric Washing Machine (초음파 직물수세기의 구성 및 구동 특성)

  • 이춘길;이광수
    • Textile Coloration and Finishing
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    • v.12 no.3
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    • pp.207-217
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    • 2000
  • A new, high-efficiency ultrasonic fabric washing machine was developed to be an energy-efficient washing machine and to enhance fabric washing quality in washing processes of the dyeing and finishing process in the textile industry. This system is composed of ultrasonic wave generator, air blowing nozzle, torque motor for fabric tension control, and enclosed washing bath, multi-tube type exchanger, noiseless heater, air cylinder, expander roller, mangle upper and lower rollers, bend bar, dancer, shower spray nozzle, and solenoid valve, and so on. These elements are synergised for fabric washing. One of the very important principles is the low tension fabric running system. For an efficient washing effect, a counter flow system is also adopted. The new system also adopts the dancer and torque motor to control fabric tension and prevent fabric creasing. Shower spray nozzle, counter flow and overflow apparatus, and air-blowing apparatus are adopted to enhance the fabric washing effect. In this study, peach yoryu, exter, and moss crepe fabrics were washed by the general and ultrasonic washing systems under different conditions respectively. The washing efficiency was affected by the fabric running speed and characteristics of fabrics. Size content after washing increased with increasing the fabric running speed. The values in the general washing system were higher than those of the ultrasonic washing system. The changes of conductivity in the ultrasonic and the cooling bath were affected by the running time under the ultrasonic generating. The values of conductivity decreased as the experimental time passed.

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Development of a Piezoelectric Ultrasonic Tooth-whitening Apparatus

  • Lee, Young-Jin;Paik, Jong-Hoo;Lee, Jeong-Bae;Choi, Seung-Jae
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.5
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    • pp.268-272
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    • 2013
  • The aim of this study was to develop an ultrasonic tooth-whitening apparatus using piezoelectric transducers, which enhance bleaching efficiency by applying ultrasound, while performing a teeth whitening procedure. For this purpose, an ultrasonic transducer was designed and manufactured, and the effects of reduction in the whitening material's concentration and in the whitening treatment time through using the ultrasound cavitation phenomenon were confirmed. Also, the validity of this study was investigated by comparing the whitening performance with a commercialized optical whitener, through color comparison. The results revealed that the ultrasound whitener produced color values that were enhanced by as much as double that of the conventional LED light whitening method. Even when the operational time was reduced by half, the ultrasound method showed superior performance by over 54% compared to the conventional light whitener, revealing that the ultrasound method showed a remarkable treatment reduction effect.