Saeb AmirAhmadi Chomachar

13 Questions 75 Answers 0 Followers

Questions related from Saeb AmirAhmadi Chomachar

Is it possible to control a control system in real domain, with a control signal which contains complex (imaginary) values?

Assume we have a control system in state space as: xdot1=u1, xdot2=u2, where x is state and u is control. I am interested to know the possibility of complex valued control signal to control such...

08 August 2019 5,349 3 View

Where can I access for literature survey on finite-length plate aerodynamics?

I need literature survey and citations for one of my research projects in regard with aerodynamic characteristics of a plate of finite- length. To my humble knowledge, I know boundary-layer theory...

11 November 2018 9,039 2 View

How will center of pressure move with increasing upstream velocity?

Assume a fluid flow which is rotational and viscous, passes over a flat plate with zero incidence. How will center of pressure move along the plate, if we increase upstream velocity. Does it move...

08 August 2018 4,434 5 View

How do you think about airflow modeled as elastic medium?

Look at the image attached. It illustrates an aircraft in uniform airflow. As the aircraft pitches down, the airflow at nose and rear of the aircraft would bend and squeeze. Since air is assumed...

07 July 2018 7,425 6 View

Why is gravity neglected for boundary layer over flat plate?

I want to know, why gravity is discarded from the Navier-Stokes equations describing boundary-layer fluid flow. Even in the wedge-flow (Falkner-Skan flow) the parameter g=9.81 does not appear....

07 July 2018 2,907 33 View

Why is engineering strain not a tensor?

Look at the image, extracted from the pdf-file attached here. Why 1/2 coefficient is much important and determines whether being tensor or not.

07 July 2018 6,210 12 View

How can I solve these plain differential equations related to fluid-flow velocity vector field?

Assume: du= f1(u,v).dx+f2(u,v).dy (1) dv= g1(u,v).dx+g2(u,v).dy (2) f1,f2, and, g1,g2 are continuous and known functions. We know further that implicitly h(u,v)=0 and hence we...

07 July 2018 6,424 10 View

How to visualize fluid-flow vector field, having implicit ode of the velocity components?

I want to have insight over fluid-flow vector field, as I have an ordinary differential equation (ode): dv/du=-2(u2+v2)/(v2 - 5u2) where u and v are horizontal and vertical velocity components...

07 July 2018 3,478 6 View

What is a good paper with literature survey on finite-strains (for fluid or solids)?

I need an article with a literature survey on contributions over large-strain (finite-strains) or similar continuum topics.

05 May 2018 6,964 6 View

What is the publication apartheid?

I have evidence that, too many global researchers belong to research secro-society. As they belong to this secret scientific community, they surreptitiously promote their colleague members and...

05 May 2018 6,026 17 View

A philosophy to validate analytical approximation to solve a mathematical algebraic equation?

I want to solve a mathematical algebraic equation. For example, T^2+exp(-T)+T^3+...=0. where T is a variable to be found. Moreover, I know T through another approach is near 5, T ≈ 5 (from...

04 April 2018 9,915 21 View

How to numerically calculate cost function, in quadratic regulator?

I am to numerically calculate the value of cost, for a certain optimal quadratic regulator. Cost in quadratic regulator is J=J(t)= int((x^2+u^2).dt, 0...inf). I have the numerical values of x and...

01 January 2018 1,946 2 View

Second-order differential equation with minute constant coefficients?

F''(t)-(1/4/pi/T)*F0*F'(t)-(6/T^2)F(t)=0. If T approaches infinity then: Am I allowed to write the equation...

09 September 2017 749 37 View