Experimental Study on Mechanical Energy Hysteresis in Nano Colloidal Damper Using Porous Silica Particle

2007 ◽  
Vol 340-341 ◽  
pp. 925-930
Author(s):  
Sang Bae Jeon ◽  
Tae Wan Ku ◽  
Jeong Kim ◽  
Beom Soo Kang

Mechanical damping systems have been widely used to various industrial structures and are mainly hydraulic and pneumatic devices nowadays. This article presents an experimental investigation of a nano colloidal damper. Particularly for colloidal damper, the hydraulic oil is replaced by a colloidal suspension, which is consisted from a nano-porous matrix with controlled architecture and a lyophobic fluid. Nano colloidal damper test rig and the measuring technique of the hysteresis were described in this study. Influence of the water volume and particle diameters upon the nano colloidal damper hysteresis was investigated. As a result, the proposed nano colloidal damper (NCD) is proved as an effective one, which can be replaced for the conventional hydraulic damper.

2007 ◽  
Vol 1007 ◽  
Author(s):  
Florent Carn ◽  
Rénal Backov

ABSTRACTHierarchically organized matter appears today a strong and highly competitive field of research mainly induced by the wide scope of applications expected. In this context, chemistry of shapes appears as a strong interdisciplinary field of research combining soft chemistry and soft matter. Hierarchical inorganic porous silica monoliths can be obtained combining air-liquid foams either with molecular precursors promoting condensation within the foam's Plateau borders confined geometry or with pre-synthesized nanobuilding blocks that will be organized within the foam's Plateau border and films. By controlling the air-liquid foam's water liquid fraction we can design the inorganic porous texture at the macroscale (i.e. cell sizes and shapes as well as the Plateau borders thickness). Considering the nanobuilding block approach, final scaffolds are a very close transcription of the tailored periodic air-liquid foam template, while highly ordered close-packed silica colloids are texturing the as-synthesized foam walls. The interconnected nanoparticles and associated void space between adjacent particles allow generating intrinsic mesopores, thereby defining hierarchically organized porous scaffolds. The good control over both the air-liquid foam's water volume fraction and the bubble size allow a rational tuning of the macropore shapes (diameter, Plateau border's width). In contrast with previous studies, closed-cell structures can be reached, while the opal like scaffold structure is maintained with thermal treatment, avoiding thus strong shrinkage associated to the sintering effect.


2017 ◽  
Vol 54 (3) ◽  
pp. 443-446
Author(s):  
Dorian Nedelcu ◽  
Aurel Bara ◽  
Adrian Pellac ◽  
Sorin Laurentiu Bogdan

The Pelton turbines convert hydraulic energy into mechanical energy, through the Pelton runner, by using high heads and small discharges. The runner has a complex geometry, described in drawings by transversal and longitudinal sections that form continuous surfaces. The SolidWorks software was used to design two Pelton runners: the R1 runner with 21 buckets and the R2 runner with 19 buckets. The runners were made of polymeric materials through the Rapid Prototyping process, using the Objet Desktop 3D printer, which is based on the Objet PolyJet technology, with a layer thickness of 28 microns [1]. The runners were used to measure the hydrodynamic characteristics of a Pelton microturbine on a test rig. The paper aims to highlight the advantages of the Rapid Prototyping process compared to the traditional technology used to manufacture Pelton runners that are intended for experimental research.


2020 ◽  
pp. 0958305X2094387
Author(s):  
Yudong Ding ◽  
Liheng Guo ◽  
Xiaoqiang Li ◽  
Qiang Liao ◽  
Xun Zhu ◽  
...  

Liquid absorption and solid adsorption technologies have been researched and reported widely for CO2 capture. Combining the advantages of these two capture materials, a novel anhydrous colloidal suspension was synthesized by dispersing amine-modified microporous silica nanospheres in 2-[2-(dimethylamino) ethoxy] ethanol. In this study, solid, hollow, and porous silica nanospheres with different internal pore structures were synthesized and characterized. The effects of the silica nanosphere microstructures on diethylenetriamine loading and CO2 absorption in anhydrous colloidal suspensions were studied. Due to a more developed pore structure, the hollow and porous silica-based absorbents possessed stronger amine loading capacities compared to solid silicon-based absorbent, and the best absorption performance was an absorption capacity of 1.2543 mmol/g at a pressure of 150 kPa and a temperature of 300 K. The results indicated that pore structure had a significant influence on the absorption property, and the porous silica-based absorbent was more favorable for CO2 absorption than solid and hollow silica-based absorbents. Moreover, the pseudo-second-order model was successful in predicting the CO2 absorption process in colloidal suspensions.


2020 ◽  
Vol 2 (2) ◽  
pp. 37-40
Author(s):  
Muhamad Rizky Septianto ◽  
Massus Subekti ◽  
Daryanto

The purpose of this study was to produce a prototype steam turbine at maket power plant steam generator torque that can play. The research method used in this research is descriptive analysis by type of engineering. Steam turbine is a Primemover that converts potential energy into mechanical energy in the form of rotation of the turbine shaft. Steam turbine constructed dimensions turbine type used single stage impulse turbine, turbine disc diameter of 33mm, the amount of movement of the blade 30 pieces, the distance between the blade 14,6mm, radious 2,63mm blade, the type of nozzle used convergent, area 3,2cm2 neck cross-section, the cross sectional area of 3,2cm2 side exit. Mockups of the steam turbine can generate 1490 rpm for turbine with a steam generator at a pressure of 4 kg/cm2 using a water volume of 19 liters. Maximum pressure that can be accepted by the steam turbine is 8 kg/cm2 with 11.000rpm, produced according to the process of heating boiler which is the maximum vapor pressure of 8kg/cm2 at a temperature of 1700C. and and be able to turn a generator with a torque of 4.6 Nm with a pressure of 8 kg/cm2 The conclusion of this study is the turbine can be built through the calculations have been carried out and taking into account the performance of the boiler and steam generator.Turbin built to produce 1336.6 rpm to spin the turbine without the steam generator at a pressure of 2 kg / cm2. Steam turbines are built to produce 1408 rpm, and generates a voltage 140.8 volts, and be able to play generatoe torque of 0.6 Nm for turbine with the steam generator at a pressure of 4 kg / cm2. Maximum pressure received by the steam turbine is 8 kg / cm2 at 10 453 rpm for the turbine without a generator, and a voltage of 271.8 volts produces, as well as being able to roll generatoe torque of 0.9 Nm for turbine with a generator on the vapor pressure of the incoming sebesae 8 kg / cm2.   Abstrak Tujuan dari penelitian ini adalah untuk menghasilkan prototipe turbin uap yang mampu memutar torsi generator. Metode penelitian yang dipakai dalam penelitian ini adalah analisis deskriptif dengan jenis rekayasa teknik. Turbin  uap (steam turbine) adalah penggerak mula yang merubah energi potensial menjadi energi mekanis dalam bentuk putaran poros turbin. Turbin uap yang dibangun memiliki dimensi jenis turbin yang digunakan turbin impuls single stage, cakram turbin berdiameter 33 mm, jumlah sudu gerak 30 buah, jarak bagi antar sudu 14,6mm, jari–jari sudu 2,63mm, jenis nosel yang digunakan konvergen, luas penampang leher 3,2cm2, luas penampang sisi keluar 3,2cm2. Maket turbin uap tersebut dapat menghasilkan 1490 rpm untuk putaran turbin dengan generator pada tekanan uap 4 kg/cm2 menggunakan volume air 19 liter. Tekanan maksimal yang mampun diterima oleh turbin uap ini adalah 8 kg/cm2 dengan 11.000rpm, sesuai yang dihasilkan pada proses memanasan boiler yaitu tekanan uap maksimalnya adalah 8kg/cm2 pada suhu 170oC. serta mampu memutar generator dengan torsi 4,6 N dengan tekanan 8 kg/cm2. Kesimpulan dalam penelitian ini adalah turbin dapat dibangun melalui perhitungan yang telah dilakukan dan dengan  mempertimbangkan  unjuk  kerja  antara  boiler  dan  generator.Turbin  uap  yang  dibangun  dapat menghasilkan 1336,6 rpm untuk putaran turbin tanpa generator pada tekanan uap 2 kg/cm2. Turbin uap yang dibangun dapat menghasilkan 1408 rpm, dan menghasilkan tegangan 140,8 volt, serta mampu memutar torsi generatoe sebesar 0,6 Nm untuk putaran turbin dengan generator pada tekanan uap 4 kg/cm2. Tekanan maksimal yang diterima oleh turbin uap ini adalah 8 kg/cm2 dengan 10.453 rpm untuk putaran turbin tanpa generator, dan menghasilkan tegangan 271,8 volt, serta mampu memutar torsi generatoe sebesar 0,9 Nm untuk putaran turbin dengan generator pada tekanan uap yang masuk sebesae 8 kg/cm2.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Yogendra Lal Verma ◽  
Manish Pratap Singh ◽  
Rajendra Kumar Singh

Silica-gel matrices containing ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate viz. ionogels have been synthesized using one-pot nonhydrolytic sol-gel method and taking tetraethyl orthosilicate (TEOS) as starting precursor. Effect of ultrasonic irradiation on pore parameters of ionogels and vibrational properties of the IL upon confinement in the porous matrix has been investigated. The synthesized gels have been characterized by BET, DSC, TGA, and FTIR. BET analysis shows some changes in the pore parameters due to ultrasonic irradiation. DSC results indicate shift in glass transition temperature upon confinement of the IL. The FTIR spectra show changes in vibrational bands on confinement, particularly, the bands related to the imidazolium ring; aliphatic chain and anionPF6 −of the IL are found to shift upon confinement in porous silica matrix obtained due to ultrasonic irradiation. Ultrasonic irradiation has been found to affect the gelation dynamics and kinetics and pore parameters.


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