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The paper presents studies on the possibility of application of loop heat pipes to a modern concept of evaporator. The potential application of such evaporator is a domestic micro CHP. One of the problems in the micro CHP is excessive demand for pumping power. The design under scrutiny here helps in overcoming that issue. In the proposed evaporator there is a possibility of reduc-ing the demand for pumping power as the evaporator will produce the extra pressure effect due to capillary forces. In such case the circulation pump oper-ates only to compensate the pressure drop due to friction losses and the wick covers the demand for overcoming the pressure drop in the expansion device. Out of 14 tested fluids 3 were selected for further scrutiny, namely ethanol, water and ammonia. It has been assumed that the fluid should work in the evap-orator at temperature of 160oC, whereas the condensation temperature is 50oC. The results of surface tension distributions with respect to temperature have been presented in figures. Preliminary analysis of the results indicates water as having the best potential, however taking into account all issues it can be said that the best effect is obtained using ethanol. Source

Tanski M.,Instytut Maszyn Przeplywowych | Barbucha R.,Instytut Maszyn Przeplywowych | Janke M.,Instytut Maszyn Przeplywowych | Garasz K.,Instytut Maszyn Przeplywowych | And 3 more authors.
Przeglad Elektrotechniczny

In this article we present the possible application of nanosecond laser micromachining in fabrication of metal MEMS element. We describe the process of laser micromachining of materials and present few examples of metal MEMS elements. We also focus on the problem of thermal degeneration of material during process of nanosecond laser micromachining. This problem is to be avoided when femtosecond laser pulses are used in MEMS laser manufacturing. Source

Barbucha R.,Instytut Maszyn Przeplywowych | Janke M.,Instytut Maszyn Przeplywowych | Garasz K.,Instytut Maszyn Przeplywowych | Kocik M.,Instytut Maszyn Przeplywowych | And 3 more authors.
Przeglad Elektrotechniczny

Recently, the most popular method to manufacture elecric circuit patterns on PCB is photolithography. This method is useless, if density of interconnections on PCB goes below 120 um/120 um (track/space width). Laser Direct Imaging method is a solution, in case of higher density of interconnetions on PCB. This article describes design of prototype system for Laser Direct Imaging. Source

Nowakowska H.,Instytut Maszyn Przeplywowych | Debicki P.,Maritime Academy of Gdynia | Mizeraczyk J.,Instytut Maszyn Przeplywowych | Mizeraczyk J.,Maritime Academy of Gdynia
Przeglad Elektrotechniczny

To find equivalent circuit of an uniform plasma column placed in a rectangular waveguide parallel to its wider wall, 2D electric field distributions have been numerically calculated and scattering as well as impedance matrix elements of a two-port network representing this waveguide determined. A T-type equivalent circuit have been proposed and influence of the plasma diameter, electron density and collision frequency and on its elements have been examined. Conditions for which the shunt impedance cannot be neglected have been determined. Source

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