Numerical Simulations of Parachute Aerodynamic Characteristics under Severe Weather

2016 ◽  
Author(s):  
Tung Wan ◽  
Chao An Cheng ◽  
Ryan Huo
Keyword(s):  
Numerical Simulations ◽  
Aerodynamic Characteristics ◽  
Severe Weather

MISSILE VERTICAL LAUNCH SYSTEM WITH REACTION CONTROL JETS

2018 ◽  
Vol 145 (1) ◽  
pp. 25-46 ◽  
Author(s):  
Robert Głębocki ◽  
Mariusz Jacewicz
Keyword(s):  
Mathematical Model ◽  
Numerical Simulations ◽  
Fuel Consumption ◽  
Rocket Engine ◽  
Unsteady Aerodynamics ◽  
Aerodynamic Characteristics ◽  
Flight Path

The paper deals with a concept of a missile vertical launch system using reaction control jets. The purpose of the study was a detailed investigation of a method optimizing fuel consumption in the first phase of the missile flight to increase the range and optimize the flight path. In the designed system the missile is ejected vertically and turned to the desired position by using corrective engines before the sustainer motor is started. The dynamics and controllability of the missile at low velocities were studied. The physical and mathematical model of the object has been described, taking into account the nonlinearities connected with the dynamics of the rocket itself, the disturbances caused by firing the rocket engine as well as some effects the unsteady aerodynamics. A method identifying the aerodynamic characteristics of the missile and an algorithm controlling the correction engines is presented. A prepared mathematical model of the missile was used to create a simulating environment. The results of numerical simulations in the form of graphs and tables are presented.

scholarly journals Aerodynamic Optimization of a Micro Quadrotor Aircraft with Different Rotor Spacings in Hover

2020 ◽  
Vol 10 (4) ◽  
pp. 1272 ◽  
Author(s):  
Yao Lei ◽  
Hengda Wang
Keyword(s):  
Numerical Simulations ◽  
Negative Impact ◽  
Aerodynamic Characteristics ◽  
Aerodynamic Performance ◽  
Aerodynamic Optimization ◽  
Quadrotor Aircraft ◽  
Blade Tip ◽  
Computational Fluid Dynamics Cfd ◽  
Aerodynamic Interference ◽  
Cfd Method

In order to study the aerodynamic performance of the quadrotor with different rotor spacings in hover, experiments were performed together with numerical simulations. For experimental study, an experimental platform was designed to measure the thrust and power consumption of the quadrotor with different rotor spacings (L/R = 2.2, 2.6, 3.0, 3.2, 3.6, and 4.0), and to attempt to find out the optimal rotor configuration which makes the quadrotor have the best aerodynamic performance. In addition, the pressure distribution, vorticity of the blade tip, and velocity vector of quadrotor in the flow field were obtained by Computational Fluid Dynamics (CFD) method to visually analyze the aerodynamic interference between adjacent rotors. By the comparison of experimental results and numerical simulations, the final results show that the aerodynamic performance of the quadrotor varies obviously with the change of rotor spacing, and it has a negative impact on hover efficiency if rotor spacing is too much small or large. The rotors pacing at L/R = 3.6 with larger thrust and smaller power is considered to be the best aerodynamic configuration for the quadrotor with better aerodynamic characteristics. Furthermore, compared with the isolated rotor, moderate aerodynamic interference is proved to help improve the aerodynamic performance of the quadrotor with a larger thrust, especially for a rotor spacing at L/R = 3.6.

Numerical Simulations and Wind Tunnel Experiments of Aerodynamic Characteristics on Waverider with Orbiter

2017 ◽  
Vol 2017.70 (0) ◽  
pp. 502
Author(s):  
Tomoki UZAKI ◽  
Tomoyuki MUTA ◽  
Nobuyuki TSUBOI ◽  
Yusuke MARU ◽  
Kazuhisa FUJITA
Keyword(s):  
Wind Tunnel ◽  
Numerical Simulations ◽  
Aerodynamic Characteristics ◽  
Wind Tunnel Experiments

scholarly journals Textile Cover Effect on Aerodynamic Characteristics of a Paraglider Wing

2019 ◽  
Vol 27 (1(133)) ◽  
pp. 78-84
Author(s):  
Paulina Maślanka ◽  
Ryszard Korycki
Keyword(s):  
Numerical Simulations ◽  
Cross Section ◽  
Symmetry Plane ◽  
Aerodynamic Characteristics ◽  
The State ◽  
Plane Model ◽  
Material Parameters ◽  
Space Model ◽  
State Variable ◽  
Spline Curves

Defined herein are the two PA-fabrics covering a paraglider wing, with the comparative object being permeable clothing material. The material parameters of textiles are applied in numerical simulations of aerodynamic characteristics using the program ANSYS. The state variable is the pressure within the airfoil profile. The space model of a paraglider wing and plane model of its cross-section in the symmetry plane are analysed. The model was approximated by the coordinates of crucial points and smoothed by the spline-curves. The visualisation of stream filaments shows that it is advisable to cover the wing with the impermeable fabric.

scholarly journals Aerodynamic Characteristics of a Stoker Furnace with Staged Combustion: Comparison of Cold Modeling Experiments and Numerical Simulations

ACS Omega ◽  
2020 ◽  
Vol 5 (27) ◽  
pp. 16332-16341
Author(s):  
Xinwei Guo ◽  
Hao Bai ◽  
Zhongxiao Zhang ◽  
Juan Yu ◽  
Degui Bi ◽  
...  
Keyword(s):  
Numerical Simulations ◽  
Aerodynamic Characteristics ◽  
Staged Combustion ◽  
Cold Modeling

scholarly journals Aerodynamic Characteristics of Radar Antenna in Stationary and Azimuthal Rotational Motion

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Yanqi Zhang ◽  
Zhaoming Zhang
Keyword(s):  
Wind Tunnel ◽  
Numerical Simulations ◽  
Rotational Motion ◽  
Pressure Coefficient ◽  
Porous Plate ◽  
Aerodynamic Characteristics ◽  
Azimuth Angle ◽  
Aerodynamic Coefficient ◽  
Solid Plate ◽  
Plate Antenna

To study the effects of aerodynamic loads on the aerodynamic characteristics of stationary and azimuthally rotating antennas, wind tunnel force tests are conducted using solid and porous plate antennas. The variation of aerodynamic coefficient with azimuth angle is obtained when the antenna is stationary and azimuthal rotation, and the results are compared with those from numerical simulations. The variation in the aerodynamic coefficients with respect to the azimuth angle is found to be sinusoidal for both the solid and porous plate antennas rotating in azimuth. Compared with the antenna stationary, quantitative analysis indicates that the rotational motion increases the maximum value and root mean square of the aerodynamic coefficient. For solid plate antenna, |Cx|_max, |Cmy|_max, and |Cmz|_max increase by 41.6%, 15.0%, and 47.3%, respectively; Cx_rms, Cmy_rms, and Cmz_rms increase by 19.0%, 20.0%, and 19.1%, respectively. For porous plate antenna, |Cx|_max, |Cmy|_max, and |Cmz|_max increase by 30.6%, 71.4%, and 40.9%, respectively; Cx_rms, Cmy_rms, and Cmz_rms increase by 22.9%, 50%, and 20%, respectively. The wind tunnel tests verify the feasibility of using numerical simulations to obtain the flow field results. By analyzing the surface pressure coefficient and vortex core track distribution, the effects of azimuthal rotation on the aerodynamic characteristics of the antenna are further clarified.

SOS: A New Design Concept for Seaway Independent Oil Skimming

2004 ◽  
Author(s):  
Gu¨nther Clauss ◽  
Mazen Abu Amro
Keyword(s):  
Experimental Investigation ◽  
Numerical Simulations ◽  
Oil Recovery ◽  
Wide Spectrum ◽  
Future Generation ◽  
Severe Weather ◽  
Operating Conditions ◽  
Design Concept ◽  
Working Principle ◽  
Rough Sea

Tanker catastrophes like the sinking of the “Erika” off the coast of Brittany and the “Prestige” off the coast of Spain revealed the shortcomings of existing oil combating systems to operate in open seas during severe weather. This paper presents various oil recovery systems of the German oil combating fleet and an analysis of their associated hydrodynamic problems. Design improvements for increasing operability and efficiency of oil recovery systems are proposed, taking advantages and drawbacks of existing oil recovery vessels into account. A new design concept is applied to the development of a Seaway Independent Oil Skimmer (SOS), which is presently being investigated at TU Berlin. A skimming module based on a new working principle enables the future generation of oil recovery vessels to operate in rough sea states. To evaluate the new oil-skimming system numerical simulations are conducted for a wide spectrum of operating conditions. The results are confirmed by experimental investigation including oil layers.

Numerical simulations of an effect produced by a cold jet propagating opposite to the incident supersonic flow on resulting aerodynamic characteristics of a blunted body

2000 ◽  
Vol 45 (9) ◽  
pp. 478-480
Author(s):  
V. M. Fomin ◽  
N. D. Malmus ◽  
A. A. Maslov ◽  
A. P. Shashkin ◽  
T. A. Korotaeva ◽  
...  
Keyword(s):  
Supersonic Flow ◽  
Numerical Simulations ◽  
Aerodynamic Characteristics ◽  
Blunted Body
Sign in / Sign up

Export Citation Format

Share Document