PSだとこう
rubyやpythonだとどうなるのかね?

$app = New-Object -ComObject Excel.Application
$app.DisplayAlerts = $false
Get-ChildItem -Path "D:\tmp\" -Recurse -Filter "*.xlsx" |
 where { $_.Name -match "^2018-\d\d-\d\d\.xlsx" } |
 foreach {
  $book = $app.Workbooks.Open($_.FullName)
  $sheets = $book.Worksheets | where { $_.Name.StartsWith("tmp") }
  $sheets | foreach { $_.Delete() | Out-Null }
  $book.Close($true)
 }
$app.Quit()