import pandas as pd
x = pd.HDFStore('test.hf', 'w', append=True)
a = pd.Series([1])
x.append('dframe', a, data_columns=True, index=False)
b = pd.Series([10,2])
x.append('dframe', b, data_columns=True, index=False)
x.close()

x = pd.HDFStore('test.hf', 'r')
print(x['dframe'])
x.close()

0     1
0    10
1     2
dtype: int64