The calculated distance (air line) between Louvain-la-Neuve and Anderlecht is approximately 18 miles respectively 28 kilometers.
By car or train, the actual journey to Anderlecht is certainly longer, as only the direct route (as the crow flies) between Louvain-la-Neuve and Anderlecht has been calculated here.
Air line (approximately)
28 kilometers
15 nautical miles