Heat transfer and friction characteristics of spirally corrugated tubes for power plant condensers—1. Experimental investigation and performance evaluation

Abstract We investigate electrokinetic behavior of colloidal particles in the vicinity of a solid-liquid interface. Colloidal liquids are expected to be used as thermal transport media for heat transfer applications such as nanofluids and phase change emulsions. They contain submicrometer-sized particles in liquid, and electrokinetic behavior of the solute particles should play an important role in the heat transfer between solid-liquid interfacing boundaries. However, experimental investigation of the behavior remains difficult due to the required spatial resolution beyond diffraction limit. We developed a measurement system based on laser Doppler principle using an interference of evanescent waves generated at total internal reflections of incident lasers at a solid wall. The system was developed for the measurement of velocities of colloidal particles at an interfacing boundary of colloidal liquid and a solid wall. The system has a unique advantage of a high spatial resolution in the direction perpendicular to the boundary due to the short penetration depth of an evanescent wave in the range of a few hundred nanometers. The principle and performance of the measurement system were investigated using a scanning probe in the measurement volume. We experimentally confirmed the validity of the measurement and characterized the uncertainty of velocity measurement. The system was further applied in a series of measurements of alumina particles dispersed in water in a square-shaped cell under induced electric fields. The measured velocities are proportional to the field strengths at different particle concentrations. The linear relationship is consistent with theoretical predictions, which demonstrates the feasibility of the system for the measurement of velocities of colloidal particles in the near wall region.

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Experimental investigation and performance evaluation of a mixed-flow air to air membrane enthalpy exchanger with different configurations

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2019.114682 ◽

2020 ◽

Vol 166 ◽

pp. 114682

Author(s):

Ahmed K. Albdoor ◽

Zhenjun Ma ◽

Paul Cooper

Keyword(s):

Experimental Investigation ◽

Performance Evaluation ◽

Mixed Flow ◽

And Performance

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ANALISA PERPINDAHAN PANAS COOLING TOWER (INDUCED DRAFT) PLTU I PULANG PISAU (2 x 60 MW)

JTAM ROTARY ◽

10.20527/jtam_rotary.v2i2.2413 ◽

2020 ◽

Vol 2 (2) ◽

pp. 171

Author(s):

I Komang Gede Sastrawan ◽

Rachmat Subagyo

Keyword(s):

Heat Transfer ◽

Power Plant ◽

Cooling Tower ◽

Cooling System ◽

Average Efficiency ◽

Condenser Temperature ◽

And Performance ◽

Cooling Media

Penelitian ini bertujuan untuk mengetahui perpindahan panas dan kinerja menara pendingin Pembangkit Listrik Pulang Pisau I (2 x 60 MW) dengan membandingkan data hasil yang diperoleh selama komisioning dan 2018. Pembangkit Listrik Pulang Pisau I (2 x 60 MW) merupakan pembangkit listrik. menggunakan sistem pendingin tertutup dengan menara pendingin. Menara pendingin pada suatu pembangkit listrik memiliki peran yang sangat penting, sebagai media pendingin utama untuk menjaga kestabilan suhu kondensor. Cooling tower merupakan salah satu peralatan perpindahan panas pada suatu pembangkit listrik. Di Pembangkit Listrik Pulang Pisau I (2 x 60 MW), kinerja menara pendingin perlu dikaji dan dianalisis bagaimana perpindahan panas dan efisiensinya untuk mendapatkan masukan guna meningkatkan / mempertahankan kinerja menara pendingin. Laju perpindahan panas tertinggi dari Pulang Pisau - PLTU Daya I 2 x 60 MW menara pendingin terjadi pada tanggal 2 Desember 2018 pukul 06.00 WIB, beban 51,0 MW yaitu 6.883 kW dan terendah terjadi pada tanggal 24 November 2018 pukul 15.00 WIB. , 14,6 MW yang merupakan 2,752 kW. Nilai efisiensi rata-rata 71%. The study aims to determine the heat transfer and performance of cooling tower Pulang Pisau I Power Plant (2 x 60 MW) by comparing the result data obtained during commissioning and 2018. Pulang Pisau I Power Plant (2 x 60 MW) is a power plant using a closed cooling system with the cooling tower. Cooling tower in a power plant have a very important role, as the main cooling media to keep the condenser temperature stable. Cooling tower is one of the heat transfer equipment in a power plant. In Pulang Pisau I Power Plant (2 x 60 MW), cooling tower performance needs to be examined and analyzed how heat transfer and efficiency are to get some input to improve / maintain the performance of the cooling tower. The highest rate of heat transfer from Pulang Pisau - Daya PLTU I 2 x 60 MW cooling tower occurred on December 2nd, 2018 at 06.00 WIB, a load of 51.0 MW which was 6.883 kW and the lowest occurred on November 24th, 2018 at 15.00 WIB, 14.6 MW which was 2.752 kW. Average efficiency value of 71%.

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