C#でＥｘｃｅｌにつけた縦10行の名前定義セルに対して値を放り込んでみる。

namespace Get_RangeTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            Excel.Application ExcelApp = new Excel.Application();
            //エクセルを非表示
            ExcelApp.Visible = false;

            //エクセルファイルのオープン
            Excel.Workbook WorkBook = ExcelApp.Workbooks.Open("C:\\test\\test.xlsx");

            //1シート目の選択
            Excel.Worksheet sheet = WorkBook.Sheets[1];
            sheet.Select();

            //A1セルのデータの取得
            Excel.Range range = sheet.get_Range("Sheet1_Range");
            if (range != null)
            {
                string[,] arry = new string[10, 1];
                arry[0, 0] = "1test";
                arry[1, 0] = "2test";
                arry[2, 0] = "3test";
                arry[3, 0] = "4test";
                arry[4, 0] = "5test";
                arry[5, 0] = "6test";
                arry[6, 0] = "7test";
                arry[7, 0] = "8test";
                arry[8, 0] = "9test";
                arry[9, 0] = "10test";

                //double[][] a = new double[][]{
                //    new  double[]{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
                //    new  double[]{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
                //    new  double[]{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }
                //};

                //var tmp = a.SelectMany(
                //    x => x.Select((item, index) => new { item, index }))
                //    .GroupBy(y => y.index, (key, z) => { return z.Average(n => n.item); }
                );

                range.Value2 = arry;
            }

            WorkBook.Save();
            //workbookを閉じる
            WorkBook.Close();
            //エクセルを閉じる
            ExcelApp.Quit();
        }