Analysis of Mechanical Characteristics of Impeller of Spray Duster Based on ANSYS Workbench

The spray dustless machine is an important environmental protection equipment for harnessing haze. The booster impeller of the spray dustless machine is one of the decisive factors of the booster capacity. The stability of the blade directly determines the reliability of the spray duster. In this paper, ANSYS Workbench is used to analyze the mechanical characteristics of a certain type of spray dustless blade. The results show that: under the rated condition, the maximum equivalent stress of the impeller is 55.6Mpa, which is far less than the allowable stress of the impeller material 415Mpa, the maximum deformation of the circumferential position at the bottom of the blade is 1.2mm, and other deformation positions are mainly the outer edge of the blade, which can be optimized later. The interference frequency is far away from the vibration frequency of the first two modes, so resonance will not occur.

WHY YACHT RUDDERS BREAK

For most sailing yachts, losing a rudder is probably the most catastrophic structural failure other than losing the keel. Rudder failure happens with distressing regularity. This paper examines the hypothesis that the underlying reason is design failure. There are many qualitative decisions to be taken in the design calculation process. Example calculations are presented which show that the maximum rudder force generated in steady state conditions is easily underestimated. For a typical spade rudder of a typical modern production sailing yacht, the normal rudder force should be calculated using a boat speed of at least 125% hull speed, and a force coefficient of at least 1.3. Care must be taken in selecting an appropriate value for the allowable stress of the material used for the stock.

SIMPLE EVOLUTIONARY STRUCURAL OPTIMIZATION FOR MULTIPLE MATERIALS

An evolutionary procedure for multiple materials is presented. A material is selected due to an allowable stress interval for the material. The presented method includes a mesh-independent filter. The proposed algorithm is applied to three examples with four or five materials. In the presented examples, the effect of an evolution rate, a filter setting, and the number of elements, are shown in a simplified way. It is shown that the final topology of structure meets the stress requirements of the materials.

Design for Displacement Strains

The allowable stress for thermal expansion and other deformation-induced stresses is substantially higher than for sustained loads. This is due to the difference between load-controlled conditions, such as weight and pressure, and deformation-controlled conditions, such as thermal expansion or end displacements (e.g., due to thermal expansion of attached equipment).

High-Pressure Piping

Chapter IX of ASME B31.3 only applies when the owner specifies its use. It applies to piping in High-Pressure Fluid Service. Note that the definition of High-Pressure Fluid Service simply requires that the owner specify use of Chapter IX. Some guidance is provided in FK300, which states “Although High Pressure Fluid Service is often considered to be service exceeding that allowed by the ASME B16.5, Class 2500 pressure-temperature rating for a particular material group, there are no pressure limitations for the application of these rules.” This is not a requirement, and the base Code may be satisfactorily used at pressures higher than ASME B16.5, Class 2500. However, the base Code rules become increasingly conservative and, in fact, impossible to use as the pressure approaches the allowable stress (including quality factors). See Section 17.3 for a discussion of pressure design of straight pipe. By the same token, Chapter IX may be used at lower pressures; it has been used with high-strength steels with pressures as low as 28,000 kPa (5,000 psi).

Allowable Load Assessment in Metal-Composite Double-Lap Joint / Avaliação de Carga Permitida em Junta de Dupla Folga Metal-Composto

This work consists of evaluating the tensile and compression static allowable stress of a hybrid (metal-composite) riveted joint. The analyzed joint is composed by two sheets of 2014 – T6 aluminium alloy and a T300/5208 Graphite/Epoxy quasi-isotropic laminate, which were joined by twelve Lockbolt Swaged Collar rivets titanium alloy Ti–6Al–4V annealed. The joint was analyzed through a computational model developed using the Finite Element Method (FEM), with the fasteners modelled through the Multi - Springs technique. This method was widely used to simulate the mechanical behaviour metal-metal and composite-composite parts of the joint. It is validated comparing its results with analytical results of metallic joints available in the literature. Through this model, both the allowable load and its distribution in the fasteners of the joint were determined. Since the evaluated joint is subjected to double shear and, therefore, has no eccentricities, the presence of secondary bending was not observed, the bearing and bypass loads were the most relevant in evaluating the allowable loads of the joint. The load distribution in the joint and its components’ safety margin was determined, with the laminate being the limiting component of the allowable load.

Pressure Vessel Mechanical Design Case study for 10 kg/cm² Pressure and 179 C Temperature

Pressure vessel is a closed tube that holds pressure, both internal pressure and external pressure. This pressure vessel is designed to function as a reservoir for condensate or condensed water and convert it into steam or hot steam. This article discusses the design of a pressure vessel for a pressure of about 10 kg/cm² and a design temperature of 179oC. In the design of this pressure vessel, it includes determining the material to be used in the design, determining the allowable stress of each material used, determining the cylinder wall thickness, cylinder head or cover wall thickness, nozzle wall thickness, determining the maximum allowable working pressure limit. or maximum allowable working pressure and testing after the pressure vessel is finished, namely the hydrostatic test method. The design has been successfully carried out according to the provisions. Bejana tekan atau pressure vessel adalah suatu tabung tertutup penampung tekanan, baik tekanan dari dalam maupun tekanan dari luar bejana. Bejana tekan yang ini dirancang berfungsi sebagai penampung condensate atau air kondensasi dan mengubahnya menjadi steam atau uap panas. Pada artikel ini dibahas perancangan pressure vessel untuk tekanan sekitar 10 kg/cm² dan suhu rancang 179oC. Dalam perancangan bejana tekan ini meliputi pemilihan material yang akan digunakan dalam perancangan, menentukan tegangan yang diijinkan atau allowable stress dari setiap material yang digunakan, menentuan tebal dinding silinder, tebal dinding head atau penutup silinder, tebal dinding nozzle, menentuan batas tekanan kerja maksimum yang diijinkan atau maximum allowable working pressure dan pengujian setelah bejana tekan jadi yaitu dengan metode hydrostatic test. Dalam artikel ini perancangan secara numeris telah berhasil dilakukan dengan baik sesuai ketentuan.

Optimal preliminary design of variable section beams criterion

The present paper discusses about optimal shape solution for a non-prismatic planar beam. The proposed model is based on the standard Timoshenko kinematics hypothesis (i.e., planar cross-section remains planar in consequence of a deformation, but it is able to rotate with respect to the beam center-line). The analytical solution for this type of beam is thus used to obtain deformations and stresses of the beam, under different constraints, when load is assumed as the sum of a generic external variable vertical one and the self-weight. The solution is obtained by numerical integration of the beam equation and constraints are posed both on deflection and maximum stress under the hypothesis of an ideal material. The section variability is, thus, described assuming a rectangular cross section with constant base and variable height which can be described in general with a trigonometric series. Other types of empty functions could also be analyzed in order to find the best strategy to get the optimal solution. Optimization is thus performed by minimizing the beam volume considering the effects of non-prismatic geometry on the beam behavior. Finally, several analytical and numerical solutions are compared with results existing in literature, evaluating the solutions’ sensibility to some key parameters like beam span, material density, maximum allowable stress and load distribution. In conclusion, the study finds a critical threshold in terms of emptying function beyond which it is not possible to neglect the arch effect and the curvature of the actual axis for every different case study described in this work. In order to achieve this goal, the relevance of beam span, emptying function level and maximum allowable stress are investigated.

DESIGN, BUILD, AND TESTING TRANSPORTATION WHEELS FOR TRANSPORTATION OF PALM OIL FRUIT IN PEATLAND

To increase the collection of oil palm yields on peatlands, the team made a design and tested the fruit vehicle using a double garden jeep. The design that is done is to make an iron wheel equipped with fins made of angled profile iron. To increase the diameter of the wheel, the standard wheels are given spokes from a 0.5 mm strip plate and are welded to the outside of the wheel with fins. The stress analysis results in the critical area show that the stress that occurs is lower than the allowable stress. The shear stress on the strip plate connected to the wheel is much less than the allowable shear stress(3 kg/cm2 ≤300 kg/cm2). Then the compressive stress that occurs is also smaller than the allowable stress (200.5 kg/cm2 ≤ 300 kg/cm2) however, the bending stress that occurs in the fins is much greater than the allowable stress (1413 kg/cm2 ≤ 400 kg/cm2), it is necessary to make additional reinforcement part fins every 10 cm. After the wheels are produced, testing is carried out by transporting 1100 kg of the palm fruit. From the results of these trials, it can be concluded that the wheel design fulfills the needs.