What is the Monte Carlo Method for Simulating Neutron Transport using MPI in C?

[Milentije]

Can anyone hepl me with this?I need some web resource,to start learning from scratch.

 

[Astronuc]

Try these to get started.

Introduction to Numerical Simulations in Radiation Transport
http://iron.nuc.berkeley.edu/%7Ebdwirth/Public/NE155/ne155.html
Notes in pdf
http://iron.nuc.berkeley.edu/%7Ebdwirth/Public/NE155/schedule.html
Several files are large.

Brief history of MCNP - Monte Carlo Neutron-Photon
http://library.lanl.gov/cgi-bin/getfile?00418730.pdf

LANL paper - A Monte Carlo Code for Particle Transport
http://www.fas.org/sgp/othergov/doe/lanl/pubs/00326727.pdf

Another historical perspective on MC -
http://library.lanl.gov/cgi-bin/getfile?00326867.pdf

MCNP site
http://mcnp-green.lanl.gov/index.html
http://mcnp-green.lanl.gov/v_r_refs.html

 

[Morbius]

Can anyone hepl me with this?I need some web resource,to start learning from scratch.

Milentije,

A very good book on Monte Carlo is by Spanier and Gelbard;
"Monte Carlo Principles and Neutron Transport Problems"

There's also another short text by Carter and Cashwell.

Dr. Gregory Greenman
Physicist

 

[Milentije]

Thanks Astronuc and Morbius,I have found the recources very usefull.

 

[freund2012]

Hello friends, I am doing simple mc simulation for neutron transport.
The principle of random simulation is L=-(1/C)*ln(u), where u is a random number from the uniform distribution [0,1), and c is the total cross section (absorbed + scattered). Could you explain me what is the meaning of u, and how can I use it in my simulation?.
I wrote a simple code in c, which I have to parallel it in MPI:

#include "mpi.h"
#include <math.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <stdbool.h>
#define PI 3.14159265
int main (int argc, char *argv[])
{
/* Simple "srand()" seed: just use "time()" */
unsigned int iseed = (unsigned int)time(NULL);
srand (iseed);

/*c = mean distance between neutron/atom interaction*/
/*cs = scattering component of c*/
/*cc = absorbing component of c*/
float c,cs,cc; /*mean distance between neutron/atom interaction*/
double h,l; /*thickness of the slab and length travelled*/
double u; /*uniform random number*/
double dd,d; /*direction of the neutron [0,pi]*/
double x; /*position particle in the plate*/
int n=10; /*number of samples*/
int bounce; /*boolean value*/
int i,r,b,t;
r=0; b=0; t=0; /*reflected,absorbed and transmited neutrons*/
/*generates randon values between 0 and 1*/
/*dd = (float) rand()/RAND_MAX;*/
for (i = 1; i <= n; i++)
{
x = 0.0;
d = 0.0;
dd = 0.0;
c = 5.5545;
cc = 0.0035;
cs = 5.551;
h = 10.00;
bounce = 1;
do {
dd = (float) rand()/RAND_MAX;
d=PI*dd;
/*generates randon values between 0 and 1*/
u = (float)rand()/RAND_MAX;
l = -(1/c)*log(u);
/*lenght traveled by the particle*/
x = x + l*cos(d);
//printf("value of x=%2.4f\n",x);
if (x < 0.0) /*reflected*/
{
r = r + 1;
bounce = 0;
// printf("reflec r= %d\n",r);
}
else {
if (x >= h) /*transmited*/
{
t = t+1;
bounce = 0;
// printf("trans t=%d\n",t);
}
else{
if (u < cc/c)
{
b = b+1;
bounce = 0;
// printf("absorbed b=%d\n",b);
}
else d = u * PI;
}
}/*end first else*/
} while (bounce = 1);
} /*end for*/
printf("Particles reflected = %d\n",dd);
printf("Particles absorbed = %d\n",b);
printf("Particles transmittedd = %d\n",b);
}/*end main*/


Please any help is more than welcome