An efficient AMG based composite solver for the fully coupled solution of the large scale ion flow field problem

•The authors provide more details for the mathematical description of the ion flow field problem and explain the irregularity introduced by the Kapzov hypothesis.•The comparison of the iteration costs under the unipolar and the bipolar cases are present to verify the efficiency of the present method.•The misleading statement about the scalability is rephrased.•The capitalization problems and other typos are revised according to the reviewers’ comments.