scholarly journals INFLUENCE OF THE OVERLAP COEFFICIENT ON THE CONTRAST IN LASER MARKING OF C110W STEEL

2021 ◽  
Vol 3 ◽  
pp. 15-19
Author(s):  
Nikolay Angelov ◽  
Lybomir Lazov ◽  
Edmunds Teirumnieks
Keyword(s):  
Experimental Data ◽  
Fiber Laser ◽  
Power Density ◽  
Tool Steel ◽  
Laser Marking ◽  
Processing Zone ◽  
Power Densities ◽  
Overlap Coefficient

The laser marking process by melting samples of C110W carbon tool steel was studied. The experiments were performed with a fiber laser and a CuBr laser. A field of squares is marked in a raster method for different values of the overlap coefficient and power density. The contrast of the marking is determined on each marked square. From the obtained experimental data, graphs of the dependence of the contrast on the overlap coefficient for three power densities were drawn. The obtained results for the two lasers are compared and the influence of the wavelength is indirectly analysed. The working intervals of the overlap coefficient for the studied power densities for the two lasers at which the optimal contrast in the processing zone is obtained are determined.

scholarly journals STUDY OF THE INFLUENCE OF DEFOCUSED LASER MARKING PROCESS BY MELTING ON SAMPLES OF STEEL

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Nikolay Angelov
Keyword(s):  
Visual Perception ◽  
Fiber Laser ◽  
Structural Steel ◽  
Laser Marking ◽  
Power Densities

The studies relate to the process of laser marking by melting on the samples of structural steel. The zone of Raleigh for fiber laser was determined. The theoretical dependences of the diameter of the working spot from defocusing and diameter of the radiation falling on the lens were received. Experiments were realized with 50G structural steel. The dependence of contrast of marking from defocusing for two power densities was determined. Working intervals were determined for studied magnitudes for visual perception of the marking.

scholarly journals INVESTIGATING THE INFLUENCE OF THE NUMBER OF REPETITIONS AND VOLUMETRIC ENERGY DENSITY ON LASER MARKING OF PRODUCTS

2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Nikolay Angelov
Keyword(s):  
Stainless Steel ◽  
Energy Density ◽  
Fiber Laser ◽  
Power Density ◽  
Experimental Results ◽  
Absorbed Energy ◽  
Laser Marking ◽  
Factors Affecting ◽  
Volumetric Density

The basic factors affecting the laser marking of products – volumetric density of the absorbed energy and the number of repetitions, were studied. Experiments were conducted of marking the samples of stainless steel with fiber laser. The dependence of the contrast of marking from the power density for different number of repetitions, and also the volumetric density of the absorbed energy from speed was obtained and the experimental results analyzed.

scholarly journals DETERMINATION OF WORKING INTERVALS OF POWER DENSITY FOR LASER MARKING OF 50ChN STEEL

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Nikolay Angelov
Keyword(s):  
Laser Radiation ◽  
Visual Perception ◽  
Fiber Laser ◽  
Power Density ◽  
Near Infrared ◽  
Laser Marking ◽  
Theoretical Considerations

Studies relate to two basic methods of steel marking − by melting and by evaporation. Based on theoretical considerations, preliminary intervals of power density for laser marking of 50 ChN steel are determined. Experiments are carried out with fiber laser, operating in the near infrared area. Graphics on the dependence of contrast of marking from the power density of laser radiation for two methods of marking were developed. Working intervals of the power density for marking by melting and by evaporation for visual perception of marking and using the readers were defined.

scholarly journals Near-field thermophotovoltaics for efficient heat to electricity conversion at high power density

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rohith Mittapally ◽  
Byungjun Lee ◽  
Linxiao Zhu ◽  
Amin Reihani ◽  
Ju Won Lim ◽  
...  
Keyword(s):  
Power Density ◽  
High Power ◽  
High Efficiency ◽  
Near Field ◽  
Electrical Power ◽  
Photovoltaic Cells ◽  
High Power Density ◽  
Pv Cell ◽  
Electrical Power Output ◽  
Power Densities

AbstractThermophotovoltaic approaches that take advantage of near-field evanescent modes are being actively explored due to their potential for high-power density and high-efficiency energy conversion. However, progress towards functional near-field thermophotovoltaic devices has been limited by challenges in creating thermally robust planar emitters and photovoltaic cells designed for near-field thermal radiation. Here, we demonstrate record power densities of ~5 kW/m2 at an efficiency of 6.8%, where the efficiency of the system is defined as the ratio of the electrical power output of the PV cell to the radiative heat transfer from the emitter to the PV cell. This was accomplished by developing novel emitter devices that can sustain temperatures as high as 1270 K and positioning them into the near-field (<100 nm) of custom-fabricated InGaAs-based thin film photovoltaic cells. In addition to demonstrating efficient heat-to-electricity conversion at high power density, we report the performance of thermophotovoltaic devices across a range of emitter temperatures (~800 K–1270 K) and gap sizes (70 nm–7 µm). The methods and insights achieved in this work represent a critical step towards understanding the fundamental principles of harvesting thermal energy in the near-field.

scholarly journals Power Density Improvement of Piezoelectric Energy Harvesters via a Novel Hybridization Scheme with Electromagnetic Transduction

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 803
Author(s):  
Zhongjie Li ◽  
Chuanfu Xin ◽  
Yan Peng ◽  
Min Wang ◽  
Jun Luo ◽  
...  
Keyword(s):  
Power Density ◽  
Output Power ◽  
Energy Harvester ◽  
Hybrid Energy ◽  
Energy Harvesters ◽  
Piezoelectric Patch ◽  
Piezoelectric Energy ◽  
Electromagnetic Transduction ◽  
Self Powered ◽  
Power Densities

A novel hybridization scheme is proposed with electromagnetic transduction to improve the power density of piezoelectric energy harvester (PEH) in this paper. Based on the basic cantilever piezoelectric energy harvester (BC-PEH) composed of a mass block, a piezoelectric patch, and a cantilever beam, we replaced the mass block by a magnet array and added a coil array to form the hybrid energy harvester. To enhance the output power of the electromagnetic energy harvester (EMEH), we utilized an alternating magnet array. Then, to compare the power density of the hybrid harvester and BC-PEH, the experiments of output power were conducted. According to the experimental results, the power densities of the hybrid harvester and BC-PEH are, respectively, 3.53 mW/cm3 and 5.14 μW/cm3 under the conditions of 18.6 Hz and 0.3 g. Therefore, the power density of the hybrid harvester is 686 times as high as that of the BC-PEH, which verified the power density improvement of PEH via a hybridization scheme with EMEH. Additionally, the hybrid harvester exhibits better performance for charging capacitors, such as charging a 2.2 mF capacitor to 8 V within 17 s. It is of great significance to further develop self-powered devices.

Giant power density produced by PIN–PMN–PT ferroelectric single crystals due to a pressure induced polar-to-nonpolar phase transformation

2021 ◽  
Author(s):  
Sergey I. Shkuratov ◽  
Jason Baird ◽  
Vladimir G. Antipov ◽  
Christopher S. Lynch ◽  
Shujun Zhang ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Energy Storage ◽  
Single Crystals ◽  
Power Density ◽  
Ferroelectric Materials ◽  
Power Supplies ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
New Generation ◽  
Power Densities

The search for ferroelectric materials capable of producing high electric charge and power densities is important for developing a new generation of ultrahigh-power-density ferroelectric energy storage devices and autonomous megawatt power supplies.

Thermal-Aware Partitioning and Encoding of Power-Gated FSM

2019 ◽  
Vol 28 (09) ◽  
pp. 1950144
Author(s):  
Priyanka Choudhury ◽  
Kanchan Manna ◽  
Vivek Rai ◽  
Sambhu Nath Pradhan
Keyword(s):  
Power Density ◽  
Power Dissipation ◽  
Hot Spots ◽  
Cmos Technology ◽  
Absolute Temperature ◽  
Temperature Management ◽  
Average Temperature ◽  
Finite State ◽  
Suitable Area ◽  
Power Densities

Miniaturization and the continued scaling of CMOS technology leads to the high-power dissipation and ever-increasing power densities. One of the major challenges for the designer at all design levels is the temperature management, particularly the local hot spots along with power dissipation. In this work, the controller circuits which are implemented as Finite State Machines (FSMs) are considered for their thermal-aware and power-aware realization. Using Genetic Algorithm (GA), both encoding and bipartitioning of the FSM circuit are implemented to get two subFSMs such that at a particular instant of time, one subFSM is active at a time, whereas the other one is power-gated. Again, thermal-aware realization (in terms of power-density) of this power-gated FSM is done. Therefore, the work concerns with the thermal-aware encoding and partitioning of FSM for its power-gated realization. Average temperature saving obtained in this approach for a set of benchmark circuits over previous works is more than 16%. After getting the final partitioned circuit which is optimized in terms of Area and power-density, thermal analysis of the sunFSMs is performed to get the absolute temperature. As thermal-aware design may increase the area, a suitable area-temperature trade-off is also presented in this paper.

Validation and Parametric Investigations of an Internal Permanent Magnet Motor Using a Lumped Parameter Thermal Model

2021 ◽  
Author(s):  
Sebastien Sequeira ◽  
Kevin Bennion ◽  
J. Emily Cousineau ◽  
Sreekant Narumanchi ◽  
Gilberto Moreno ◽  
...  
Keyword(s):  
Experimental Data ◽  
Sensitivity Analysis ◽  
Permanent Magnet ◽  
Power Density ◽  
Heat Removal ◽  
Maximum Difference ◽  
Modeling Framework ◽  
Element Analysis ◽  
Lumped Parameter ◽  
Input Parameters

Abstract One of the key challenges for the electric vehicle industry is to develop high-power-density electric motors. Achieving higher power density requires efficient heat removal from inside the motor. In order to improve thermal management, a multi-physics modeling framework that is able to accurately predict the behavior of the motor, while being computationally efficient, is essential. This paper first presents a detailed validation of a Lumped Parameter Thermal Network (LPTN) model of an Internal Permanent Magnet synchronous motor within the commercially available Motor-CAD® modeling environment. The validation is based on temperature comparison with experimental data and with more detailed Finite Element Analysis (FEA). All critical input parameters of the LPTN are considered in detail for each layer of the stator, especially the contact resistances between the impregnation, liner, laminations and housing. Finally, a sensitivity analysis for each of the critical input parameters is provided. A maximum difference of 4% - for the highest temperature in the slot-winding and the end-winding - was found between the LPTN and the experimental data. Comparing the results from the LPTN and the FEA model, the maximum difference was 2% for the highest temperature in the slot-winding and end-winding. As for the LTPN sensitivity analysis, the thermal parameter with the highest sensitivity was found to be the liner-to-lamination contact resistance.

Sign in / Sign up

Export Citation Format

Share Document