Rancang Bangun Oil System untuk Turbocharger Gas Turbine Engine Dengan Inducer Diameter 1,75 Inch

Rancang bangun mesin turbin gas dimulai dengan mengidentifikasi beberapa komponen yang dibutuhkan dalam membangun sebuah mesin turbin gas. Turbocharger yang terdiri dari kompresor dan turbin sebagai penyusun utama komponen ini diambil untuk dijadikan Kompresor dan turbin mesin turbin gas yang juga merupakan unsur utama dalam sebuah mesin turbin gas. Agar sebuah mesin turbin gas dapat beroperasi maka perlu dirancang beberapa system pendukung seperti Oil System, Fuel System, Ignation System, Combustion Chamber dan beberapa system yang lain. Pada perancangan ini, penulis mendapat bagian dalam perancangan Sistem pelumas (Oil System) dimana tantangan yang dihadapi adalah mendapatkan jenis oil yang tepat untuk mesin turbin gas yang akan dibangun. Adapun rumusan masalah dalam perancangan system pelumas ini antara lain bagaimana menentukan viskositas pelumas yang digunakan, menghitung critical pressure bearing, menghitung jumlah pelumas yang digunakan, menghitung head pompa dan menghitung kapasitas reservoir yang digunakan. Output akhir yang dihasilkan dari perancangan ini adalah suplai oli yang mampu untuk melumasi shaft bearing pada turbocharger sehingga tidak terjadi overheating yang menyebabkan keausan serta metal to metal contact. Dari hasil perhitungan, didapatkan tekanan oli sebesar 37 psi yang diperlukan untuk melumasi shaft bearing pada turbocharger. Dan dihasilkan pembakaran yang continuous.

A Thermophotovoltaic System Using a Photonic Crystal Emitter

The increasing power demands of portable electronics and micro robotics has driven recent interest in millimeter-scale microgenerators. Many technologies (fuel cells, Stirling, thermoelectric, etc.) that potentially enable a portable hydrocarbon microgenerator are under active investigation. Hydrocarbon fuels have specific energies fifty times those of batteries, thus even a relatively inefficient generator can exceed the specific energy of batteries. We proposed, designed, and demonstrated a first-of-a-kind millimeter-scale thermophotovoltaic (TPV) system with a photonic crystal emitter. In a TPV system, combustion heats an emitter to incandescence and the resulting thermal radiation is converted to electricity by photovoltaic cells. Our approach uses a moderate temperature (1000–1200°C) metallic microburner coupled to a high emissivity, high selectivity photonic crystal selective emitter and low bandgap PV cells. This approach is predicted to be capable of up to 30% efficient fuel-to-electricity conversion within a millimeter-scale form factor. We have performed a robust experimental demonstration that validates the theoretical framework and the key system components, and present our results in the context of a TPV microgenerator. Although considerable technological barriers need to be overcome to realize a TPV microgenerator, we predict that 700–900 Wh/kg is possible with the current technology.

Study on the Calculation of Boron Combustion in Different Oxidizing Atmospheres

The calculations of thermal equilibrium of B/O and B/C/H/O/N system were done based on the principle of Gibbs minimum free energy by HSC Chemistry software. The results indicated that in B/O system when B/O mole ratio is kept at 2:3, the main gas phase boron contained products transform from B2O3(g) to BO(g) and BO2(g) with increase of temperature. Improving the environmental pressure is beneficial to increase the heat release of boron combustion. As to B/C/H/O/N system, B/C/H/O/N mole ratio is settled to be 2:1:2:6:1. The main combustion products are N2(g), HBO2(g), CO2(g), H2O and B2O3(g) when the environmental temperature is relatively low in the case that the heat release of fuel can be obtained enough. When the environmental temperature rises, the major combustion products are CO(g), BO(g) and so on. It shows that high temperature is not beneficial for heat release of boron combustion. Like B/O system, improving the environmental pressure helps to increase the heat release of B/C/H/O/N system combustion.

Study on the Modification and Performance of Compressed Natural Gas Engine

To modify a diesel engine into a natural gas engine, the supplying system, intake system, ignition system, combustion system and post-processing system are redesigned to meet the requirements of applying natural gas on the engine. Then on the basis of calibration of basic ignition advance angle and volumetric efficiency of natural gas engine, bench test is done to study the velocity performance, load performance and universal performance, as well as a comprehensively evaluation on the performance of natural gas engine. The result indicates that the modifying of nature gas engine is reasonable as it achieves the application of CNG on the engine and a comprehensive performance of engine.