CFD MODELING OF MICROCHANNELS COOLING FOR ELECTRONIC MICRODEVICES

A simulation of the cooling of electronic devices was carried out by means of microchannels, using water as a coolant to dissipate the heat generated from a computer processor, and thus stabilize its optimum operating temperature. For the development of this study, computational fluid mechanics modeling was established in order to determine the temperature profiles, pressure profiles, and velocity behavior of the working fluid in the microchannel. In the results of the study, the operating temperatures of the computer processor were obtained, in the ranges of 303 K to 307 K, with fluid velocities in the microchannels of 5 m/s, a pressure drop of 633.7 kPa, and a factor of safety of the design of the microchannel of 15. From the results, the improvement of the heat transfer in a cooling system of electronic devices was evidenced when using a coolant as a working fluid compared to the cooling by forced air flow traditional. ABSTRAK: Simulasi penyejukan alatan elektronik telah dibina menggunakan saluran mikro, di samping air sebagai agen penyejuk bagi menghilangkan haba yang terhasil dari pemproses komputer, dan penstabil pada suhu operasi optimum. Kajian ini mengenai model komputasi mekanik bendalir bagi menentukan profil suhu, profil tekanan, dan halaju perubahan bendalir dalam saluran mikro. Dapatan kajian menunjukkan suhu operasi pemproses komputer adalah pada julat suhu 303 K sehingga 307 K, dengan halaju bendalir dalam saluran mikro adalah pada kelajuan 5 m/s, penurunan tekanan sebanyak 633.7 kPa, dan faktor keselamatan 15 bagi reka bentuk saluran mikro. Ini menunjukkan terdapat kenaikan pemindahan haba bagi sistem penyejukan alatan elektronik ini, terutama apabila cecair digunakan sebagai penyejuk haba berbanding kaedah tradisi iaitu dengan mengguna pakai aliran udara sebagai agen penyejuk.

Moore’s Law revisited through Intel chip density

Gordon Moore famously observed that the number of transistors in state-of-the-art integrated circuits (units per chip) increases exponentially, doubling every 12–24 months. Analysts have debated whether simple exponential growth describes the dynamics of computer processor evolution. We note that the increase encompasses two related phenomena, integration of larger numbers of transistors and transistor miniaturization. Growth in the number of transistors per unit area, or chip density, allows examination of the evolution with a single measure. Density of Intel processors between 1959 and 2013 are consistent with a biphasic sigmoidal curve with characteristic times of 9.5 years. During each stage, transistor density increased at least tenfold within approximately six years, followed by at least three years with negligible growth rates. The six waves of transistor density increase account for and give insight into the underlying processes driving advances in processor manufacturing and point to future limits that might be overcome.

Parallel Scalable Approximate Matching Algorithm for Network Intrusion Detection Systems

Matching algorithms are working to find the exact or the approximate matching between text “T” and pattern “P”, due to the development of a computer processor, which currently contains a set of multi-cores, multitasks can be performed simultaneously. This technology makes these algorithms work in parallel to improve their speed matching performance. Several exact string matching and approximate matching algorithms have been developed to work in parallel to find the correspondence between text “T” and pattern “P”. This paper proposed two models: First, parallelized the Direct Matching Algorithm (PDMA) in multi-cores architecture using OpenMP technology. Second, the PDMA implemented in Network Intrusion Detection Systems (NIDS) to enhance the speed of the NIDS detection engine. The PDMA can be achieved more than 19.7% in parallel processing time compared with sequential matching processing. In addition, the performance of the NIDS detection engine improved for more than 8% compared to the current SNORT-NIDS detection engine

Space Complexity of C Compiler and Lex Tool

We can never stop stressing on the purpose and the importance of the compiler in the field of computer science. compiler does translates the high level programs like C,C++,java ,python and so on into low level language (machine language ) which in turn computer processor use. Though the job of the compiler is to translate, depending on the properties of the programming languages the time complexity, space complexity and some of the other characteristics varies accordingly. Thus the purpose of the paper is concentrated on comparing such factors significantly the C compiler and the Lex tool. Our study reveals the best memory consumption among c compiler and lex tool.

Polymetric analysis and cybernetics

Basic concepts of Polymetric Analysis as universal system of formalization the knowledge are discussed. Correlation between Polymetrric Analysis and cybernetics is researched. It was shown that cybernetics as synthetical science is similar to Polymetric Analysis. But Polymetric Analysis may be represented as functional expansion of computer processor and therefore may be applied for the resolution the problems of artificial intelligence, pattern recognition and other chapters of modern cybernetics. This problem is analyzed with point of S. Beer centurial problem in cybernetics (problem of complexity of information) and has system nature

Rational Approximation for Solving an Implicitly Given Colebrook Flow Friction Equation

The empirical logarithmic Colebrook equation for hydraulic resistance in pipes implicitly considers the unknown flow friction factor. Its explicit approximations, used to avoid iterative computations, should be accurate but also computationally efficient. We present a rational approximate procedure that completely avoids the use of transcendental functions, such as logarithm or non-integer power, which require execution of the additional number of floating-point operations in computer processor units. Instead of these, we use only rational expressions that are executed directly in the processor unit. The rational approximation was found using a combination of a Padé approximant and artificial intelligence (symbolic regression). Numerical experiments in Matlab using 2 million quasi-Monte Carlo samples indicate that the relative error of this new rational approximation does not exceed 0.866%. Moreover, these numerical experiments show that the novel rational approximation is approximately two times faster than the exact solution given by the Wright omega function.

Simulation of cooling of a processor in nanosatellite using the loop heat pipes

One of the key problems in the development of nanosatellites is to provide a given temperature range for the operation of electronic equipment, the heat transfer of which can be tens of watts. Thermoregulation systems traditional for large spacecraft are not suitable for nanosatellites due to limitations on their mass and size characteristics. The indicated thermal regime of nanosatellites can be achieved using remote heat removal systems - miniature loop heat pipes. In recent years, their mass production has been established in Russia, but they have not yet found wide application in nanosatellites. The aim of the paper is to substantiate the possibility of using miniature loop heat pipes to remove excess heat from the on-board computer processor to the carbon-plastic case of the nanosatellite. Parametric modeling of the influence of geometric dimensions and the values of the effective thermal conductivity coefficient of loop heat pipes on the processor temperature was carried out in the ANSYS program. Calculations showed that the use of contour heat pipes will reduce the processor temperature to acceptable values. The anisotropy of the thermal conductivity coefficient in the reinforcement plane of the composite material of the nanosatellite case can have a significant effect on the temperature of the processor. This opens up prospects for the use of anisotropic composite materials to ensure the thermal regime of the nanosatellite.