Numerical simulation of added mass determination of standard ellipsoids

Raza, Naveed; Mehmood, Imran; Rafiuddin, Hafiz; Rafique, Mohsin

doi:10.1109/ibcast.2012.6177564

Cited by 7 publications

(6 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(4) As a method of verification in contrast to process (2), this step employs the parameter separation method to solve for the three parameters â , b , and ĉ . Seven sets of uniform motion simulations are added.…”

Section: Methodsmentioning

confidence: 99%

“…That is, if two rigid bodies are moving at the same speed, the one that is accelerating will be subjected to a greater force from the water. The underlying reason for this is that when the rigid body accelerates, the surrounding fluid will also accelerate, as if additional mass was attached to the rigid body, resulting in an increase in the body's inertia [1,2]. Added mass, a classical concept in the field of fluids, was proposed by researchers and has been widely studied for many years.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Simulation and Analysis of Added Mass for the Underwater Variable Speed Motion of Small Objects

Wang,

Xiao,

Wang

et al. 2024

JMSE

View full text Add to dashboard Cite

Unlike uniform motion, when an object moves underwater with variable speed, it experiences additional resistance from the water, commonly referred to as added mass force. At present, several methods exist to solve this force, including theoretical, experimental, and simulation approaches. This paper addresses the challenge of determining the added mass force for irregularly shaped small objects undergoing variable speed motion underwater, proposing a method to obtain the added mass force through numerical simulation. It employs regression analysis and parameter separation analysis to solve the added mass force, added mass, viscous drag coefficient, and pressure drag coefficient. The results indicate that an added mass force exists during both the acceleration and deceleration of the object, with little difference between them. Under the same velocity conditions, significant differences exist in pressure drag forces, while differences in viscous drag forces are not significant. This suggests that the primary source of added mass force is pressure drag, with viscous drag having little effect on it. During acceleration, the surrounding fluid accelerates with the object, increasing the pressure drag with a high-pressure area concentrating at the object’s front, forming an added mass force that is directed backward. By contrast, during deceleration, the fluid at the object’s front tends to detach, and the fluid at the rear rushes forward, leading to a smaller high-pressure area at the front and a larger one at the rear, reducing the pressure drag and forming an added mass force that is directed forward. By comparing the added mass of a standard ellipsoid obtained from numerical simulation with theoretical values, the regression analysis method is proven to be highly accurate and entirely applicable for solving the added mass of underwater vehicles.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Numerical Simulation and Analysis of Added Mass for the Underwater Variable Speed Motion of Small Objects

Wang,

Xiao,

Wang

et al. 2024

JMSE

View full text Add to dashboard Cite

show abstract

“…At present, there are many researches on the numerical calculation of the added mass of underwater vehicle and flight vehicle at home and abroad [2][3][4][5], on the contrary, little study can be found about the automobile. Lan et al [6] numerically simulated the flow field of a fast-back sedan in the starting process, the result indicates that during this process, the aerodynamic drag has an obvious increase, however, it didn't analyze the correlation between the increase of drag and added mass, also didn't provide the calculation method about the increase of drag.…”

Section: Introductionmentioning

confidence: 99%

Theoretical and Numerical Calculation on the Added Mass of Ahmed Body

2017

AMM

View full text Add to dashboard Cite

Because of the added mass, the aerodynamic drag of the automobile will increase obviously when accelerating in the still air. In this paper, it firstly gave the definition of the added mass, and presented that there was little research on the calculation of the added mass of automobile. Then through the analysis of the theoretical calculation method for the added mass, it pointed out that, for the added mass of the car-body with a complex shape, there was much difficulty in the theoretical calculation. Alternatively, a numerical calculation method for the added mass of car-body was derived. The simulation model adopted the Ahmed body and the corresponding verification experiment was completed in the Tongji Automotive Wind Tunnel center. The results indicate that the added mass is a constant which is only dependent on the body-shape. For the model investigated, the added mass is 0.0052kg that is approximately equal to the air displaced by the car-body. As the body accelerates to 4m/s2, the aerodynamic drag is increased by 1.89% because of added mass. Therefore, it needs to pay more attention to the impact that the added mass has on the dynamic performance of vehicle when proceeding the aerodynamic designs (especially for the high power performance vehicles). Meanwhile, it still makes a correction to the conventional aerodynamic drag formula. This paper also demonstrates that, with the analysis of the flow-field of car-body, the added mass essentially stems from the additionally work done by the car-body to increase the kinetic energy of external fluid as it speeds up.

show abstract

“…If the above equation is written in the matrix form, which is the general form of the added mass matrix, the following matrix is introduced [14].…”

Section: Discretization Of Equationsmentioning

confidence: 99%

“…The added mass coefficients of the Darpa Suboff submarine were calculated by means of the FMBEM [13]. Naveed Raza et al determined the added mass by simulating the flow about a standard ellipsoid using a commercial CFD code [14]. Recently, a 3-D boundary element method was used by Gaschler and Abdel-Maksoud (2014) to compute the added mass coefficients for a marine propeller under cavitating condition [15].…”

Section: Introductionmentioning

confidence: 99%