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求助各位大佬，用NEMD法算铜的热导率一直算出来只有个位数，远低于实际，检查了好几天实在不知道什么原因引起，in文件如下：
#Cuga-Gr
#model parameter
units metal
boundary p p p
atom_style full
timestep 0.001 #1fs
neighbor 2.0 bin
neigh_modify every 1 delay 0
#modeling
lattice fcc 3.61 #晶格常数
region box block 0 10 0 10 0 50 #区域
create_box 1 box
create_atoms 1 box
region hot block INF INF INF INF 0 1
region cold block INF INF INF INF 25 26
#--------------------混合势函数设置------------------------------
pair_style meam/c
pair_coeff * * library.meam Cu Cu.meam Cu
#-------------------热力学输出----------------------------
compute Thot all temp/region hot
compute Tcold all temp/region cold
thermo 100
#--------------------能量最小化-----------------------
min_style cg
minimize 1e-15 1e-15 5000 5000
#-------------------npt系综下驰豫--------------------
reset_timestep 0
fix 1 all npt temp 300 300 0.01 iso 0 0 0.1
dump 1 all atom 100 dump.colloid
run 1000
thermo_modify lost ignore
unfix 1
#注入热量
fix 2 all nve
fix hot all heat 10 10 region hot
fix cold all heat 10 -10 region cold
thermo_style custom step temp c_Thot c_Tcold
thermo 1000
run 10000
compute ke all ke/atom
variable temp atom c_ke/0.0001292355
compute layers all chunk/atom bin/1d z lower 0.05 units reduced
fix 3 all ave/chunk 10 100 1000 layers v_temp file profile.heat
variable tdiff1 equal f_3[11][3]-f_3[1][3]
variable tdiff2 equal f_3[6][3]-f_3[4][3]
variable t1 equal f_3[1][3]
variable t2 equal f_3[2][3]
variable t3 equal f_3[3][3]
variable t4 equal f_3[4][3]
variable t5 equal f_3[5][3]
variable t6 equal f_3[6][3]
variable t7 equal f_3[7][3]
variable t8 equal f_3[8][3]
variable t9 equal f_3[9][3]
variable t10 equal f_3[10][3]
variable t11 equal f_3[11][3]
variable t12 equal f_3[12][3]
variable t13 equal f_3[13][3]
variable t14 equal f_3[14][3]
variable t15 equal f_3[15][3]
variable t16 equal f_3[16][3]
variable t17 equal f_3[17][3]
variable t18 equal f_3[18][3]
variable t19 equal f_3[19][3]
variable t20 equal f_3[20][3]
fix ave1 all ave/time 1 1 1000 v_tdiff1 ave running start 13000
fix ave2 all ave/time 1 1 1000 v_tdiff2 ave running start 13000
fix a1 all ave/time 1 1 1000 v_t1 ave running start 13000
fix a2 all ave/time 1 1 1000 v_t2 ave running start 13000
fix a3 all ave/time 1 1 1000 v_t3 ave running start 13000
fix a4 all ave/time 1 1 1000 v_t4 ave running start 13000
fix a5 all ave/time 1 1 1000 v_t5 ave running start 13000
fix a6 all ave/time 1 1 1000 v_t6 ave running start 13000
fix a7 all ave/time 1 1 1000 v_t7 ave running start 13000
fix a8 all ave/time 1 1 1000 v_t8 ave running start 13000
fix a9 all ave/time 1 1 1000 v_t9 ave running start 13000
fix a10 all ave/time 1 1 1000 v_t10 ave running start 13000
fix a11 all ave/time 1 1 1000 v_t11 ave running start 13000
fix a12 all ave/time 1 1 1000 v_t12 ave running start 13000
fix a13 all ave/time 1 1 1000 v_t13 ave running start 13000
fix a14 all ave/time 1 1 1000 v_t14 ave running start 13000
fix a15 all ave/time 1 1 1000 v_t15 ave running start 13000
fix a16 all ave/time 1 1 1000 v_t16 ave running start 13000
fix a17 all ave/time 1 1 1000 v_t17 ave running start 13000
fix a18 all ave/time 1 1 1000 v_t18 ave running start 13000
fix a19 all ave/time 1 1 1000 v_t19 ave running start 13000
fix a20 all ave/time 1 1 1000 v_t20 ave running start 13000
thermo_style custom step temp c_Thot c_Tcold v_tdiff1 v_tdiff2 f_ave1 f_ave2 f_a1 f_a2 f_a3 f_a4 f_a5 f_a6 f_a7 f_a8 f_a9 f_a10 f_a11 f_a12 f_a13 f_a14 f_a15 f_a16 f_a17 f_a18 f_a19 f_a20 v_t1 v_t2 v_t3 v_t4 v_t5 v_t6 v_t7 v_t8 v_t9 v_t10 v_t11 v_t12 v_t13 v_t14 v_t15 v_t16 v_t17 v_t18 v_t19 v_t20
run 20000
最后输出的结果如图，温差太大，
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发表于 Post on 2024-7-4 23:16:18
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楼主 Author
同学，我也想问问。我是用了几种办法（包括你用的热浴，还有速度重标）来算碳纳米管的热导率，但是我不仅仅是输出结果差了2~3倍，重点是温度分布也很差，几乎是乱的