提交: be27b5118aa0ebdcc1f3afa0ce7cff3528d4c3af - myprojects-hg-reborn (hg)

Commit MetaInfo

• 修订版: be27b5118aa0ebdcc1f3afa0ce7cff3528d4c3af (tree)
• 时间: 2007-07-10 23:21:44
• 作者: iselllo
• Commiter: iselllo

Log Message

Now air-mean-free-path.py calculated the total and time-dependent
thermophoretic deposition efficiency assuming a specific representative
size for the particles involved. Also the plots are now saved in a
specific directory.

更改概述

• modified: Python-codes/air-mean-free-path.py

差异

diff -r 8eb0114540a0 -r be27b5118aa0 Python-codes/air-mean-free-path.py
--- a/Python-codes/air-mean-free-path.py	Tue Jul 10 14:18:54 2007 +0000
+++ b/Python-codes/air-mean-free-path.py	Tue Jul 10 14:21:44 2007 +0000
@@ -2,6 +2,7 @@
 from scipy import *
 import pylab
 
+
 def v_th(T):
 	k_B=1.38e-23
 	m_air=28.8*1.66e-27
@@ -55,7 +56,7 @@
 	
 	return K_tb
 	
-def K_talbot(T):
+def K_talbot(T,diam_seq):
 	lam_air=l_air(T)
 	#print 'lam_air is',lam_air
 	#print 'diam_seq is', diam_seq
@@ -72,7 +73,7 @@
 	return K_tb
 
 def V_thermo(T):
-	K=K_talbot(T)
+	K=K_talbot(T,diam_seq)
 	nu=nu_T(T)
 	Re=U*2.*R/nu
 	Nusselt=0.023*Re**0.8*Prandtl**0.4
@@ -80,107 +81,161 @@
 	return vel
 
 
+def f_th(T,t):
+	theta_star=T_w/(T-T_w)
+	K=K_talbot(T,diam_seq)
+	nu=nu_T(T) #viscosity, NOT the Nusselt number!
+	Re=U*2.*R/nu
+	Nusselt=0.023*Re**0.8*Prandtl**0.4
+	z=((theta_star+exp(-2.*Nusselt*U*t/(R*Re*Prandtl)))/(1+theta_star))**(Prandtl*K)
+	return z
+
+def f_th_asym(T,t):
+	theta_star=T_w/(T-T_w)
+	K=K_talbot(T,diam_seq)
+	nu=nu_T(T)
+	Re=U*2.*R/nu
+	Nusselt=0.023*Re**0.8*Prandtl**0.4
+	z=(theta_star/(1+theta_star))**(Prandtl*K)
+	return z
+
+	
+
+
+
+
 #l_air_vec=vectorize(l_air)
-T=linspace(293.,450.,100)
-T_new=T
+T_seq=linspace(293.,450.,100)
+#T_new=T
 #p=zeros(len(T))
 p=101325. #1atm in bars
 
-
+t=linspace(0.,20.,400)
 
-l_mean=map(l_air,T)
+#################################################################################
+#In the following calculations I vary the temperature and fix the particle size#######
+#################################################################################
 
-diam_seq=70.e-9
+l_mean=map(l_air,T_seq)
 
-pylab.plot(T,l_mean,linewidth=2.)
+diam_seq=70.e-9 #I fix the particle size
+
+pylab.plot(T_seq,l_mean,linewidth=2.)
 pylab.xlabel('Temperature[K]',fontsize=20.)
 pylab.ylabel('air mean free path [m]',fontsize=20.)
 #pylab.legend(('prey population','predator population'))
 pylab.title('Air Mean Free Path',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('air_free_path')
+pylab.savefig('./plots-air-mean-free-paths/air_free_path')
 
 pylab.hold(False)
 
-k_air=cond_air(T)
+k_air=cond_air(T_seq)
 
-pylab.plot(T,k_air,linewidth=2.)
+pylab.plot(T_seq,k_air,linewidth=2.)
 pylab.xlabel('Temperature[K]',fontsize=20.)
 pylab.ylabel('air conductivity [W/mK]',fontsize=20.)
 #pylab.legend(('prey population','predator population'))
 pylab.title('Gas Conductivity',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('air_conductivity')
+pylab.savefig('./plots-air-mean-free-paths/air_conductivity')
 
 pylab.hold(False)
 
 
 
-mu=mu_T(T)
+mu=mu_T(T_seq)
 
-pylab.plot(T,mu,linewidth=2.)
+pylab.plot(T_seq,mu,linewidth=2.)
 pylab.xlabel('Temperature[K]',fontsize=20.)
 pylab.ylabel('air dynamic viscosity [Kg/(m*s)]',fontsize=20.)
 #pylab.legend(('prey population','predator population'))
 pylab.title('Air dynamic viscosity',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('air_dynamic_viscosity')
+pylab.savefig('./plots-air-mean-free-paths/air_dynamic_viscosity')
 
 pylab.hold(False)
 
-rho=rho_T(T)
+rho=rho_T(T_seq)
 
 
-pylab.plot(T,rho,linewidth=2.)
+pylab.plot(T_seq,rho,linewidth=2.)
 pylab.xlabel('Temperature[K]',fontsize=20.)
 pylab.ylabel('air density [Kg/m**3]',fontsize=20.)
 #pylab.legend(('prey population','predator population'))
 pylab.title('Air density',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('air_density')
+pylab.savefig('./plots-air-mean-free-paths/air_density')
 
 pylab.hold(False)
 
-pylab.plot(T,mu/rho,linewidth=2.)
+pylab.plot(T_seq,mu/rho,linewidth=2.)
 pylab.xlabel('Temperature[K]',fontsize=20.)
 pylab.ylabel('air kinematic viscosity [Kg/(m*s)]',fontsize=20.)
 #pylab.legend(('prey population','predator population'))
 pylab.title('Air kinematic viscosity',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('air_kinematic_viscosity')
+pylab.savefig('./plots-air-mean-free-paths/air_kinematic_viscosity')
 
 pylab.hold(False)
 
 #print 'rho and T are', rho, T
 
+
+
+
+######################################################################
+#Now I fix T (i.e. T_0) and consider later on a set of particle sizes#########
+####################################################################
+
+
 #Now I choose a particular value of T and save the properties of air
 input_air=pylab.load('input_air')
 input_air=input_air*1.0 # to get a floating point array
-T=input_air[0] # careful about what I choose here to get a sensible estimate of air properties
+T_0=input_air[0] # careful about what I choose here to get a sensible estimate of air properties
 T_w=273.+70.
-print 'T_0 and T_w are', T,T_w
+print 'T_0 and T_w are', T_0,T_w
 data_save=zeros(6)
 
-#p=p[1]
 
-data_save[0]=T
-data_save[1]=l_air(T)
-data_save[2]=nu_T(T) 
-data_save[3]=mu_T(T)
-data_save[4]=rho_T(T)
+
+data_save[0]=T_0
+data_save[1]=l_air(T_0)
+data_save[2]=nu_T(T_0) 
+data_save[3]=mu_T(T_0)
+data_save[4]=rho_T(T_0)
 # although it is not calculated here at all, but it is simply an experimental datum,
 # I add here the mean axial velocity, which is also included into the input file
 U=input_air[1]
-Prandtl=0.679 # treated a constant
+Prandtl=0.69 # treated a constant
 R=0.05 # radius of the anaconda
 data_save[5]=U
 
+#Now some calculations of the depositio efficiency: I fixed T_0 and the particle size
+#is still fixed
+
+f_time=f_th(T_0,t)
+
+f_no_time=zeros(len(f_time))
+f_no_time[:]=f_th_asym(T_0,t)
+
+#print 'f_no_time is', f_no_time
+
+pylab.plot(t,f_time,t,f_no_time,linewidth=2.)
+pylab.xlabel('Ut [m]',fontsize=20.)
+pylab.ylabel('Thermophoretic Deposition Efficiency',fontsize=20.)
+#pylab.legend(('prey population','predator population'))
+pylab.title('Thermophoretic Deposition',fontsize=20.)
+pylab.grid(True)
+pylab.savefig('./plots-air-mean-free-paths/thermophoretic_deposition_efficiency')
+
+#pylab.hold(False)
 
 pylab.save("output_air", data_save)
 
 print 'data_save is', data_save
 
-nu_2=-1.1555e-14*T**3. + 9.5728e-11*T**2. + 3.7604e-08*T - 3.448e-06
+nu_2=-1.1555e-14*T_0**3. + 9.5728e-11*T_0**2. + 3.7604e-08*T_0 - 3.448e-06
 
 #print 'the two estimates of nu are', data_save[2], nu_2
 
@@ -188,21 +243,21 @@
 knudsen=logspace(-2.,1.,10)
 Ra=1e-3
 
-K_thermo=K_talbot_test(T,knudsen,Ra)
+K_thermo=K_talbot_test(T_0,knudsen,Ra)
 
 #pylab.semilogx(knudsen,K_thermo,linewidth=2.)
 #pylab.xlabel('knudsen number',fontsize=20.)
 #pylab.ylabel('K_th',fontsize=20.)
 #pylab.title('Thermophoretic coefficient',fontsize=20.)
 #pylab.grid(True)
-#pylab.savefig('thermophoretic_coefficient')
+#pylab.savefig('./plots-air-mean-free-paths/thermophoretic_coefficient')
 
 #pylab.hold(False)
 
 
 #diam_seq=linspace(2.,600.,100)
 
-diam_seq=pylab.load("D_mean_seq")
+diam_seq=pylab.load("D_mean_seq")  #now diam_seq stands for a list of diameters
 
 diam_seq=diam_seq/1e9 
 
@@ -210,7 +265,7 @@
 
 #print "diam_seq is", diam_seq
 
-K_bis=K_talbot(T)
+K_bis=K_talbot(T_0,diam_seq)
 #print 'K_bis is', K_bis
 print 'the shape of k_bis is', shape(K_bis)
 
@@ -218,24 +273,27 @@
 pylab.plot((diam_seq*1e9),K_bis,linewidth=2.)
 pylab.xlabel('diameter [nm]',fontsize=20.)
 pylab.ylabel('K_th',fontsize=20.)
-pylab.title('Thermophoretic coefficient at T=350K',fontsize=20.)
+pylab.title('Thermophoretic coefficient at fixed T-T_w',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('thermophoretic_coefficient_vs_particle_diameter')
+pylab.savefig('./plots-air-mean-free-paths/thermophoretic_coefficient_vs_particle_diameter')
 
 pylab.hold(False)
 
-V_th=V_thermo(T)
+V_th=V_thermo(T_0)
+
+
 
 pylab.plot((diam_seq*1e9),V_th,linewidth=2.)
 pylab.xlabel('diameter [nm]',fontsize=20.)
 pylab.ylabel('K_th',fontsize=20.)
-pylab.title('Thermophoretic velocity',fontsize=20.)
+pylab.title('Thermophoretic velocity at fixed T-T_w',fontsize=20.)
 pylab.grid(True)
-pylab.savefig('thermophoretic_velocity_vs_particle_diameter')
+pylab.savefig('./plots-air-mean-free-paths/thermophoretic_velocity_vs_particle_diameter')
 
 pylab.hold(False)
 
 pylab.save('v_thermophoresis',V_th)
 
+#Now I calculate the deposition efficiency
 
 print 'So far so good'
\ No newline at end of file