A computational methodology for a micro launcher engine test bench using a combined linear static and dynamic in frequency response analysis
Journal Title: INCAS BULLETIN - Year 2017, Vol 9, Issue 1
Abstract
This article aims to provide a quick methodology to determine the critical values of the forces, displacements and stress function of frequency, under a combined linear static (101 Solution - Linear Static) and dynamic load in frequency response (108 Solution - Frequency Response, Direct Method), applied to a micro launcher engine test bench, using NASTRAN 400 Solution - Implicit Nonlinear. NASTRAN/PATRAN software is used. Practically in PATRAN the preprocessor has to define a linear or nonlinear static load at step 1 and a dynamic in frequency response load (time dependent) at step 2. In Analyze the following options are chosen: for Solution Type Implicit Nonlinear Solution (SOL 400) is selected, for Subcases Static Load and Transient Dynamic is chosen and for Subcase Select the two cases static and dynamic will be selected. NASTRAN solver will overlap results from static analysis with the dynamic analysis. The running time will be reduced three times if using Krylov solver. NASTRAN SYSTEM (387) = -1 instruction is used in order to activate Krylov option. Also, in Analysis the OP2 Output Format shall be selected, meaning that in bdf NASTRAN input file the PARAM POST 1 instruction shall be written. The structural damping can be defined in two different ways: either at the material card or using the PARAM, G, 0.05 instruction (in this example a damping coefficient by 5% was used). The SDAMPING instruction in pair with TABDMP1 work only for dynamic in frequency response, modal method, or in direct method with viscoelastic material, not for dynamic in frequency response, direct method (DFREQ), with linear elastic material. The Direct method – DFREQ used in this example is more accurate. A set in translation of boundary conditions was used and defined at the base of the test bench.
Authors and Affiliations
Ion DIMA, Adrian TOADER, Dragos Daniel ION GUTA, Mircea BOCIOAGA
Keywords
Related Articles
- EP ID EP292424
- DOI 10.13111/2066-8201.2017.9.1.3
- Views 89
- Downloads 0
Tribological performance of the blend PBT and short aramid fibers
Polybutylene terephthalate (PBT) and its aramid fiber composite (10 wt.%) were investigated in order to measure their wear and frictional properties under variations of applied load (5 N, 10 N, 15N) and velocity (0.25 m/...
Design methods of Coanda effect nozzle with two streams
This paper continues recent research of the authors about the ACHEON Coanda effect two streams nozzle. This nozzle aims to produce an effective deflection of a propulsive jet with a correspondent deviation of the thrust...
Method for mitigating the negative effect of vortex motion inside the suction chambers of centrifugal pumps
The paper presents a method for mitigating the negative effect of vortex motion inside the suction chambers of centrifugal pumps in order to obtain better use of water resource and decrease the risk related to loss of pr...
The Evolution of Missile Defense Plan from Bush to Obama. Implications for the National Security of Romania
In 2011 Romania officially became part of the Obama administration’s missile defense system in Europe which has significantly changed the strategic military relations both in Europe and worldwide. The Bush approach has b...
Towards the Effects of Initial Grain Temperature and Erosive Burning on the Solid Propellant Combustion
On the basis of an improved mathematical model it was explored how the derived nonlinear pressure coupling response function, depending on pressure and frequency, behaves at extreme initial grain temperatures. This is ac...