Coupled Shaft-Torsion and Blade-Bending Vibrations of a Rotating Shaft–Disk–Blade Unit

1996 ◽  
Vol 118 (1) ◽  
pp. 100-106 ◽  
Author(s):  
S. C. Huang ◽  
K. B. Ho
Keyword(s):  
Rotation Axis ◽  
Limited Extent ◽  
Shaft Speed ◽  
Rigid Support ◽  
Dynamic Coupling ◽  
Weighted Residual Method ◽  
Rotating Shaft ◽  
Bending Vibrations ◽  
New Approach ◽  
Shaft Flexibility

A new approach to analyzing the dynamic coupling between shaft torsion and blade bending of a rotating shaft–disk–blade unit is introduced. The approach allows the shaft to vibrate freely around its rotation axis instead of assuming a periodic perturbation of the shaft speed that may accommodate the shaft flexibility only to a limited extent. A weighted residual method is applied, and the receptances at the connections of blades and shaft–disk are formulated. Numerical examples are given for cases with between two and six symmetrically arranged blades. The results show not only coupling between the shaft, disk, and blades, but also coupling between individual blades where the shaft acts as a rigid support and experiences no torsional vibration. The blade-coupling modes occurred only in repeated frequencies. Finally, the effect of shaft speed on the modal frequencies was investigated. Plots illustrating the occurrence of critical speeds and flutter instabilities are presented.

scholarly journals Modifikasi Sistem Transmisi pada Mesin Pencacah Sampah/Limbah Plastik dengan Sistem Crusher dan Silinder Pemotong Tipe Reel

2016 ◽  
Vol 11 (2) ◽  
pp. 42
Author(s):  
Junaidi - ◽  
Ichlas Nur ◽  
Zulfikar - ◽  
Nasirwan -
Keyword(s):  
Rotation Axis ◽  
Engine Performance ◽  
Performance Testing ◽  
Transmission System ◽  
Motor Shaft ◽  
Rotating Shaft ◽  
Plastic Recycling ◽  
Technical Evaluation ◽  
Second Year ◽  
Engine Capacity

An increasing number of plastic waste, but can be recycled into other products in the form of granules before further processing into a grain pellets and injection molding processes to produce products such as buckets, plates, bottles and others. To be processed into the required form of granules of plastic thrasher. Even so small plastic recycling industry is still constrained within a plastic enumeration process because the machine used his ability was not maximal.The purpose of this study is a modification of the transmission system thrasher plastic crusher system and cylinder-type cutter reel and technical evaluation. This study was conducted over two years, the first year the design and manufacture of machinery, the second year is the technical evaluation of the engine, improved engine performance. From the results of the study year I found some weaknesses machines namely, 1) the machine is often hampered by the transmission belt on the motor shaft with shaft reducer as drive unit crusher often slip when a large load, 2) transmission gears hipoid of the motor shaft with shaft type unit reel get a great friction and cause the sound very noisy. To improve the performance of the engine of the transmission system needs to be fixed.From the results of the design redesign the engine in the second year, namely, the installation of a connector axle of the motor shaft with shaft-type knife reel player. Axle used is commonly used in car axle Carry. Likewise, the transmission system between the motor shaft to the reducer as a successor to the rotation axis of the blade type crusher players use the chain sprocket to avoid slip on a rotating shaft. The results of performance testing crusher machine on lap 75 RPM and cylinder-type reel cutters 1450 RPM, engine capacity ± 130 kg / h on the cylinder type crusher and the reel-type cylinder engine capacity of ± 165 kg / h at an aperture sieve Ø 1,5 cm, with uniformity of grain 85%.

Development of a self-pumping extracorporeal blood oxygenation device characterized by a rotating shaft with embedded fiber packages

2019 ◽  
Vol 43 (6) ◽  
pp. 393-400
Author(s):  
Antonino Rinaudo ◽  
Salvatore Pasta
Keyword(s):  
Blood Flow ◽  
Rotation Axis ◽  
Blood Oxygenation ◽  
Operating Conditions ◽  
Respiratory Support ◽  
Gas Transfer ◽  
Animal Testing ◽  
Rotating Shaft ◽  
Hollow Shaft

Introduction: To offer respiratory support for patients with lung disease, a novel technological solution for blood pumping and oxygenation is being developed. The pump–lung system was designed to integrate fiber membranes into six packages radially embedded in a rotating hollow shaft placed along the longitudinal axis of the device. Fiber packages are inclined with respect to the rotation axis so that the rotational motion of the rotating shaft allows a self-pumping system to be obtained. Method: Both hemodynamic and gas transfer performances were investigated using both in vitro experiments and in silico flow analyses. Results: The predicted flow velocity in the pump chamber was smooth and characterized by high peripheral velocities near the housing wall. As the blood flow enters the inlet, the static pressure increased with the angular momentum imparted to the fiber packages. Experiments confirmed that the proposed pump–lung system can provide adequate blood flow and oxygen transfer over the range of intended operating conditions (0.5–5 L/min and 500–1500 r/min). Conclusion: Although the study did not include animal testing, the novel pump-oxygenator solution is feasible for respiratory support in patients with lung diseases.

Numerical Analysis of the Flow Field Within Lip Seals Containing Microundulations

1992 ◽  
Vol 114 (3) ◽  
pp. 485-491 ◽  
Author(s):  
R. F. Salant
Keyword(s):  
Numerical Analysis ◽  
Flow Field ◽  
Shear Deformation ◽  
Leakage Rate ◽  
Shaft Speed ◽  
Rotating Shaft ◽  
Lip Seal ◽  
Lubricating Film ◽  
Lip Seals

The flow field within the lubricating film of a rotating shaft lip seal containing microundulations is analyzed numerically. The results demonstrate that the action of the microundulations can prevent leakage through the seal. The effects on leakage rate of shaft speed, undulation amplitude and wavelength, shear deformation of the undulations, flattening of the undulations, and axial lip profile are presented.

Linear Dynamic Coupling in Geared Rotor Systems

1986 ◽  
Vol 108 (2) ◽  
pp. 171-176 ◽  
Author(s):  
J. W. David ◽  
L. D. Mitchell
Keyword(s):  
Gear Tooth ◽  
Equations Of Motion ◽  
Dynamic Coupling ◽  
Rotating Shaft ◽  
Rotor Systems ◽  
Linear Dynamic ◽  
Heavy Lift ◽  
Reaction Forces ◽  
Coupling Terms ◽  
Nonlinear Equations Of Motion

The ability to analyze accurately the torsional-axial-lateral coupled response of geared systems is the key to the prediction of dynamic gear forces, shaft moments and torques, dynamic reaction forces, and moments at all bearing points. These predictions can, in turn, be used to estimate gear-tooth lives, shaft lives, housing vibrational response, and noise generation. Typical applications would be the design and analysis of gear drives in heavy-lift helicopters, industrial speed reducers, Naval propulsion systems, and heavy, off-road equipment. In this paper, the importance of certain linear dynamic coupling terms on the predicted response of geared rotor systems is addressed. The coupling terms investigated are associated with those components of a geared system that can be modeled as rigid disks. First, the coupled, nonlinear equations of motion for a disk attached to a rotating shaft are presented. The conventional argument for ignoring these dynamic coupling terms is presented and the error in this argument is revealed. It is shown that in a geared system containing gears with more than about 50 teeth, the magnitude of some of the dynamic-coupling terms is potentially as large as the magnitude of the linear terms that are included in most rotor analyses. In addition, it is shown that the dynamic coupling terms produce the multi-frequency responses seen in geared systems. To quantitatively determine the effects of the linear dynamic-coupling terms on the predicted response of geared rotor systems, a trial problem is formulated in which these effects are included. The results of this trial problem shows that the inclusion of the linear dynamic-coupling terms changed the predicted response up to eight orders of magnitude, depending on the response frequency. In addition, these terms are shown to produce sideband responses greater than the unbalanced response of the system.

scholarly journals The effect of processing parameters on energy consumption of ball mill refiner for chocolate

2013 ◽  
Vol 67 (5) ◽  
pp. 747-751 ◽  
Author(s):  
Aleksandar Fistes ◽  
Dusan Rakic ◽  
Biljana Pajin ◽  
Ljubica Dokic ◽  
Ivana Nikolic
Keyword(s):  
Energy Consumption ◽  
Ball Mill ◽  
Vertical Cylinder ◽  
Processing Parameters ◽  
Maximum Speed ◽  
Shaft Speed ◽  
Rotating Shaft ◽  
Power Requirement ◽  
Grinding Media ◽  
Steel Balls

A laboratory ball mill consisting of vertical cylinder, equipped with a rotating shaft with arms, and filled with steel balls as a grinding medium has been used in the experiments. The aim of the study was to examine the effect of agitator shaft speed and amount of grinding media (steel balls) on power requirements and energy consumption of a ball mill. With constant mass of the steel balls (20 kg, 30 kg and 40 kg), the agitator shaft speed was increased from 10% to 100% of the maximum speed which corresponds to a speed of 50 rpm. The power consumption (W) was recorded upon which milling energy consumption (J/kg) has been calculated. The results were statistically analyzed using ANOVA. The increase of the agitator shaft speed, in steps of 10% to the maximum speed of 50 rpm, led to a statistically significant increase in milling energy consumption. At low agitator shaft speed (10%), increase in the mass of the steel balls had no influence on the power requirements. Power requirements for the grinding runs using 30 kg and 40 kg are similar and higher compared to power requirement in trial with 20 kg, as agitator shaft speed increases from 20% to 70%. At high agitator shaft speeds (?80%), increase in steel balls mass led to the significant increase in power requirements of the ball mill.

A new approach for detecting topographic and geologic information in seismic data

Geophysics ◽  
2012 ◽  
Vol 77 (2) ◽  
pp. V81-V90 ◽  
Author(s):  
Adam Gersztenkorn
Keyword(s):  
Seismic Data ◽  
Computational Cost ◽  
Wavelet Domain ◽  
3D Seismic ◽  
Limited Extent ◽  
Complex Matrix ◽  
New Approach ◽  
Additional Information ◽  
Seismic Volumes ◽  
Topographic Aspect

Interpreting 3D seismic volumes can be an intensive and time-consuming endeavor. Algorithms that provide additional information and expedite this process can therefore be useful tools for the interpreter. To further this goal, an algorithm that gives a topographic perspective of seismic data is described. After applying the continuous wavelet transform to the data, templates having a directional orientation are constructed locally in the complex wavelet domain for a number of scales. For each scale, a complex matrix is formed having real and imaginary parts, which are independently designed for a specific purpose and then combined to produce the final result. Whereas the composition of the real matrix is not well suited for dealing with the topographic aspect of the data, the imaginary matrix is. Using basic concepts from graph theory, the imaginary matrix is constructed to reveal the topographic nature of the underlying data. To a limited extent, dip scans provide similar results. Nonetheless, comparisons with dip scans reveal significant differences in the final results and computational efficiency. Although the general features seem to be similar, detailed features appear to be missing from the dip scan results. For the dip scans, semblance is measured over a number of dips and the highest value is used to determine the dip. The computational cost can vary, depending on factors such as the number of dips tested and implementation, but a comparison indicates that dip scans can be computationally more costly. In contrast, the algorithm to be described uses a single suite of wavelets convolved with the data to produce a number of scale-dependent complex matrices that are summed in a specific way. Furthermore, convolutions may be performed in the frequency domain. This reduces the computational cost, making this algorithm an effective and relatively fast interpretation tool.

scholarly journals Perancangan dan Pengujian Kinerja Mesin Pencacah Tulang Ikan

2020 ◽  
Vol 15 (1) ◽  
pp. 73
Author(s):  
Wahyu Tri Handoyo ◽  
Luthfi Assadad ◽  
Bakti Berlyanto Sedayu
Keyword(s):  
Performance Test ◽  
Fish Meal ◽  
Rapid Development ◽  
Fish Bone ◽  
Raw Material ◽  
Shaft Speed ◽  
Rotating Shaft ◽  
Working Mechanism ◽  
Trash Fish ◽  
And Performance

Tepung ikan merupakan salah satu komoditas penting akuakultur yang permintaannya di Indonesia meningkat setiap tahun seiring pesatnya perkembangan akuakultur. Sebagian besar kebutuhan tepung ikan tersebut dipenuhi dari impor. Salah satu upaya untuk mengurangi kebutuhan impor adalah  memanfaatkan berbagai jenis ikan rucah dan sisa olahan ikan berupa tulang dan kepala ikan sebagai bahan baku tepung ikan. Permasalahan yang dihadapi pada pengolahan tulang ikan adalah proses pencacahan menjadi ukuran yang lebih kecil. Oleh karena itu diperlukan mesin yang mampu mencacah tulang ikan yang memiliki tekstur keras. Telah dilakukan perancangan, pembuatan dan pengujian kinerja mesin pencacah tulang ikan. Mesin dirancang berdasarkan mekanisme kerja poros berputar untuk menggerakkan sepasang mata pisau yang saling berhimpitan dan berputar berlawanan arah. Uji kinerja dilakukan dengan beban tulang ikan tuna dengan variasi perlakuan frekuensi inverter 25; 37,5; dan 50 Hz. Parameter yang diamati meliputi rendemen, kecepatan putaran poros, waktu pencacahan, dan kapasitas pencacahan. Hasil uji coba menunjukkan bahwa semakin tinggi frekuensi inverter, kecepatan putaran poros semakin tinggi, sehingga kapasitas pencacahan semakin meningkat. Berdasarkan parameter yang diamati, mesin bekerja optimal pada frekuensi inverter 50,0 Hz.  AbstractFish meal is one of the essential inputs for aquaculture, and the demand in Indonesia is growing every year parallel with the rapid development of aquaculture. Most of the fish meal was imported. An effort to reduce imports is to utilize various types of trash fish and fish processing waste, including bones and head as raw material for fish meal. The problem that occurs in the processing of fish bone is the process of chopping them into smaller sizes. Therefore, a machine capable of chopping hard texture of fish bones is needed. The design and performance tests of the fish bone chopping machine have been conducted. The device was designed based on the working mechanism of the rotating shaft to drive the paired blades that coincide and rotate in the opposite direction. The performance test was carried out for tuna bone with varied inverter frequencies of 25; 37,5; and 50 Hz. The parameters observed were yield, shaft speed, chopping time, and capacity. The results showed that increasing inverter frequency increased the shaft speed; therefore, it increased the capacity. Based on the observed parameters, the machine worked optimally at an inverter frequency of 50,0 Hz.

TWO-DIMENSIONAL BINGHAM PLASTIC FLOW IN A CYLINDRICAL PRESSURISED CLUTCH

1994 ◽  
Vol 08 (20n21) ◽  
pp. 2955-2965 ◽  
Author(s):  
R. J. ATKIN ◽  
T. J. CORDEN ◽  
T. G. KUM ◽  
W. A. BULLOUGH
Keyword(s):  
Flow Model ◽  
Maximum Yield ◽  
Leakage Rate ◽  
Two Dimensional ◽  
Shaft Speed ◽  
Shaft Seal ◽  
Rotating Shaft ◽  
Bingham Plastic ◽  
Theory And Experiment ◽  
Laminar Flow Model

An examination of the capability of an energised electro-rheological fluid to act as a rotating shaft seal is reported. A two-dimensional laminar flow model based on a Bingham plastic flowing between parallel plate electrodes indicated that leakage would always occur whenever the shaft was in rotation, whatever the magnitude of the pressure gradient along the sealing annulus. This result was confirmed in experiments, the results of which show some discrepancy between theory and experiment in the magnitude of the leakage rate. However this error is accountable and is acceptable in the area of immediate interest-shaft speed of circa 1000/1500 rpm and at maximum yield or electro-stress.

Rotating, Axially Loaded Timoshenko Shaft: Modeling and Stability

1993 ◽  
Author(s):  
Gerald Karch ◽  
Jörg Wauer
Keyword(s):  
Boundary Value Problem ◽  
Nonlinear Boundary ◽  
Boundary Value ◽  
Beam Theory ◽  
Rotating Shaft ◽  
Bending Vibrations ◽  
Starting Point ◽  
Constant Magnitude ◽  
The Stability ◽  
Linear Boundary Value Problem

Abstract For studying the stability of a rotating shaft subject to axial load, the derivation of correct stability equations is the essential preliminary problem. Here, the model of a uniform non-circular Timoshenko shaft under a compressive end load of constant magnitude is dealt with. Starting point is the nonlinear boundary value problem for coupled extensional-bending-torsional oscillations where a finite strain beam theory in a floating reference frame following the rigid body rotation is applied. First, the equation set describing the stationary shaft configuration is deduced. Next, the variational equations for small superimposed perturbations are derived. The only interesting stability problem for usual properties of the shaft cross section is constituted by a linear boundary value problem describing the bending vibrations. The corresponding characteristic equation is evaluated finally to find the critical buckling load also for the case of an oval shaft not considered before.

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