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1

Design modification of water wheel turbine with various configuration variations

Firman Firman, Yunus Mohammed Yusuf, Anshar Muhammad, Hamzah Nur, Klistafani Yiyin, Djalal Muhammad Ruswandi

Przegląd Elektrotechniczny

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2023

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R. 99, nr 6

230--236

EN

One of the obstacles in the open loop cooling system is that the seawater that will be discharged back to the source does not meet the requirements for the quality standards for generation wastewater. So that the waste water pit requires a long channel construction. The construction of a long waste water pit channel is needed so that convectional heat transfer occurs in the channel to achieve the temperature requirements of the generated waste water, which is around 30o C. In this study, 4 fin configuration variations were used, namely: Ʌ-shaped four-angled fins, V-shaped four-angled fins, two parallel transverse four-angled fins (═), and two parallel four-pointed fins longitudinally (||) . With open channel dimensions of 7 m × 0.1 m × 1.3 m and the dimensions of the water wheel turbine model, namely diameter: 0.4 m, blade size: 0.8 × 0.8 m and a total of 16 blades. Based on the research results it is known that the type of fin that has the ability to reduce temperature quickly is the type of two fins with four parallel transverse angles with a temperature drop of 5.56o C with a tilt position of 0o , while the temperature drop with a tilt position of 30o is 4.54o C. However, this type of fin generates little power because the water that hits the turbine blades will be accommodated on the inside of the turbine fin even by utilizing a large discharge. The type of fin that produces the highest efficiency (%) and output power (Watts) is the type of two parallel four-angled longitudinal fins (||) with the highest efficiency value of 61.71% on a slope of 0o C and 84.95% on a slope of 30o C in order to obtain the greatest output power of 0.48 Watt at a slope of 0 o C and 0.56 Watt at a slope of 30o C.

PL

Jedną z przeszkód w systemie chłodzenia z obiegiem otwartym jest to, że woda morska, która będzie odprowadzana z powrotem do źródła, nie spełnia wymagań norm jakościowych dla wytwarzania ścieków. Aby studzienka ściekowa wymagała budowy długiego kanału. Konieczna jest budowa długiego kanału ściekowego, aby w kanale następowała konwekcyjna wymiana ciepła w celu osiągnięcia wymaganej temperatury wytwarzanych ścieków, która wynosi około 30oC. W tym badaniu zastosowano 4 warianty konfiguracji płetw, a mianowicie: czterokątne płetwy w kształcie Ʌ, czterokątne płetwy w kształcie litery V, dwie równoległe poprzeczne czterokątne płetwy (═) i dwie równoległe czteroramienne płetwy wzdłużnie (| |) . O wymiarach otwartego kanału 7 m × 0,1 m × 1,3 m oraz wymiarach modelu turbiny koła wodnego, a mianowicie średnicy: 0,4 m, wielkości łopatek: 0,8 × 0,8 m i łącznie 16 łopatek. Na podstawie wyników badań wiadomo, że typem płetwy, który ma zdolność szybkiego obniżania temperatury jest typ dwóch płetw z czterema równoległymi kątami poprzecznymi o spadku temperatury 5,56oC przy pozycji pochylenia 0o, natomiast spadek temperatury przy pozycji pochylenia 30o wynosi 4,54oC. Jednak ten typ płetwy generuje niewielką moc, ponieważ woda, która uderza w łopatki turbiny, będzie zatrzymywana po wewnętrznej stronie płetwy turbiny, nawet przy dużym wypływie. Typ płetwy, który zapewnia najwyższą wydajność (%) i moc wyjściową (W) to typ dwóch równoległych, czterokątnych podłużnych płetw (||) o najwyższej wartości sprawności 61,71% na zboczu 0oC i 84,95% na zboczu nachylenie 30oC w celu uzyskania jak największej mocy wyjściowej 0,48 W przy nachyleniu 0 oC i 0,56 W przy nachyleniu 30oC.

2

On the beam radiance of mid-infrared quantum cascade lasers : a review

Mroziewicz Bohdan, Pruszyńska-Karbownik Emilia

Opto-Electronics Review

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2019

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Vol. 27, No. 2

161--173

EN

Lasers emitting mid-infrared (MIR) beams have become indispensable for spectroscopy, free space communication or remote security measures. To the one of the most promising families of the lasers suitable for these applications certainly belongs a group of the Quantum Cascade Lasers (QCL). However, among the conditions they must satisfy there is a high enough radiance of the beam they emit. Radiance depends in a complicated way on the laser output power and optical quality of the laser beam. This paper has been devoted to a description and a short analysis of the factors that decide about radiance of so far developed QCLs. Literature concerning both single devices and QCL arrays operating in beam combining systems have been examined and results described. The survey may be useful for estimation of how far the QCLs have come of age.

3

A New Method for an Electric Vehicle Wireless Charging System Using LCC

Khademi Hamid Reza, Moghaddam Mahmoud Samiei, Baygi Seyed Javad Mohammadi, Hajizadeh Amin

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 3

98--112

EN

Nowadays, there is a need for charging electric vehicles (EVs) wirelessly, since it provides a more convenient, reliable, and safer charging option for the EV customers. A wireless charging system using a double-sided LCC compensation topology is proven to be highly efficient; however, the large volume induced by the compensation coils is a drawback. Endocrine links are more useful in transmitting power wirelessly than other links. These links are used in the transmission of low and medium power. In this paper, by analyzing the equivalent circuit of a WPT power transmission system, the optimal value of the inductance was formulated to increase the yield. This can have other applications. In order to neutralize the reactive losses, the series resonance is used in both in primary and secondary sections, among which the lower quantities of series inductors were selected from the initial values to increase the efficiency and power. Furthermore, it is possible to optimize these values using suitable optimization methods. In this study, the PSO algorithm was used for this purpose.

4

Numerical investigation of an impact of a top gold metallization on output power of a p-up III-N-based blue-violet edge-emitting laser diode

Kuc M., Sarzała R. P., Stańczyk S., Perlin P.

Opto-Electronics Review

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2015

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Vol. 23, No. 2

131-136

EN

The effect of modifications in epi-side (top) gold metallization on a thermal performance and on power roll-over of blue-violet III-N-based p-up edge-emitting ridge-waveguide laser diode (RW EEL) was explored in this paper. The calculations were carried out using a two-dimensional self-consistent electrical-thermal model combined with a simplified optical model tuned to a RW EEL fabricated in the Institute of High Pressure Physics (Unipress). Our results suggest that with proper modifications in the III-N-based RW EEL, excluding modifications in its inner structure, it is possible to considerably improve the thermal performance and, thus, increase the maximal output power.

5

Optical external efficiency calculation for mid-infrared quantum cascade laser

Hamadou A.

Optica Applicata

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2011

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Vol. 41, nr 3

717--725

EN

In this paper, we present a simple method for calculation of optical external efficiency of mid-infrared quantum cascade laser. The approach is based on the three-level rate equations describing the variation of the electron number in the excited states and the photon number present within the cavity. We have obtained a simple analytical formula for the optical external efficiency. The effects of cavity lengths and current injection are taken into account. It has been found that the optical external efficiency becomes more important at high current injection and at lower cavity lengths.

6

Modelling of laser pumped intracavity frequency doubled laser.

Jabczyński J.K.

Optica Applicata

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2000

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Vol. 30, nr 1

161-171

EN

A model of an intracavity frequency doubled laser pumped by a laser beam was elaborated. The effects connected with mode matching, thermal lensing, pump induced diffraction losses, as well as parameters of frequency conversion and geometry of cavity were considered. An analytical model of the cavity with an internal lens and thermal lensing was derived to optimize output characteristics. Two types of cavity (with and without internal lens) were analyzed and the best configurations with respect to second harmonic output power were found for both cases. The pump induced diffraction losses were found to limit the output power of the frequency doubled laser for high pump levels.