How to draw concentric arcs in a 120 degree sector and the contour plots for mass flux of water spray in each concentric compartment ?

Question

raghav sikka 2022-4-12

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1694430-how-to-draw-concentric-arcs-in-a-120-degree-sector-and-the-contour-plots-for-mass-flux-of-water-spra

回答： raghav sikka 2022-4-13

%% for polar plot

theta = linspace(0,120,8); % angle division

rho = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values

polarplot(theta,rho)

%% to plot concentric arcs

n = 120;

r = 0:0.01:0.75;

r=r';

theta = pi*(0:(n))/180;

Y = r*cos(theta);

X = r*sin(theta);

plot(X,Y)

%% contour plots for mass flux density

x1 = 0.05:.10:0.75; % radius (in m) at which concentric arcs are drawn for 120 ° sector

x2 = linspace(0,120,8); % angle division

[X1, X2]= meshgrid(x1,x2);

z = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values

figure

contourf (x1, x2, z)

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Chunru 2022-4-12

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1694430-how-to-draw-concentric-arcs-in-a-120-degree-sector-and-the-contour-plots-for-mass-flux-of-water-spra#answer_940815

编辑：Chunru 2022-4-12

在 MATLAB Online 中打开

%% for polar plot

theta = linspace(0,120,8); % angle division

rho = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values

polarplot(deg2rad(theta),rho) % use radian for theta

%% to plot concentric arcs

% (change the order of theta and r)

n = 120;

r = 0:0.01:0.75;

theta = deg2rad(0:n);

X = cos(theta') * r;

Y = sin(theta') * r;

plot(X,Y); axis equal

%% contour plots for mass flux density

% z = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values

% z should be compatible with x1 and x2, e.g.

Z = sqrt(X.^2 + Y.^2);

figure

contourf (X, Y, Z); axis equal

%% For data r and z

r = [0.05, 0.15,0.25,0.35,0.45,0.55,0.65,0.75]; %sector radius

z1 = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009];

X = cos(theta') * r;

Y = sin(theta') * r;

Z = repmat(z1, [length(theta), 1]);

figure

contourf (X, Y, Z, 5); axis equal

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Answer 2

raghav sikka 2022-4-12

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1694430-how-to-draw-concentric-arcs-in-a-120-degree-sector-and-the-contour-plots-for-mass-flux-of-water-spra#answer_940905

Thanks for reply ! I forgot to convert in radian..

I am afraid the rho vector (mass flux values) is defined based on radius 'r' not theta as like in polar plot such that first value 0.000959931) corresponds to (first) inner most concentric sector of radius 0.05 m and so on...

rho = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values

The first (inner) concentric sector is 0.05 m in radius, then 0.10 m difference until radius r = 0.75 m.

7 个评论
显示 5更早的评论隐藏 5更早的评论

raghav sikka 2022-4-12

Thank you.

yes, I agree it needs more data to make it smoother.

But we have 8 levels only. can we plot only 8 levels in contour? also, why there is a gap at center region (white) ?

How to replicate it for other two sectors to make it a full concentric circle (360 deg)?

Chunru 2022-4-13

If you do want to use exactly 8 levels for the similar data you have provided, you can consider to use "patch". doc patch for more info.

The center region white gap is due to no data along that part (rho does not start from 0)

For full concentric plot, you need to make theta 360 deg. For three sectors, you can hold on and plot other two sectors on same plot.

请先登录，再进行评论。

Answer 3

raghav sikka 2022-4-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1694430-how-to-draw-concentric-arcs-in-a-120-degree-sector-and-the-contour-plots-for-mass-flux-of-water-spra#answer_941755

r = [0.05, 0.15:0.1:0.75]; % gives 8 sectors

rho = [0.000959931, 0.051254502, 0.025132741, 0.099483767, 0.174300215, 0.134972129, 0.0429351, 0.015068009]; % mass flux values .... why still gap at the center?

How to use patch(x,y) for each concentric sector (r=0.05,0.15:0.1:0.75); ?