The region of flow over which the t

The region of flow over which the thermal boundary layer develops and reaches the tube center is
called the thermal entry region, and the length of this region is called the thermal entry length. The region in which the flow is both hydrodynamically (the velocity profile is fully developed and remains unchanged) and thermally (the dimensionless temperature profile remains unchanged) developed is called the fully developed region.

Hasil (Bahasa Indonesia) 1:

Daerah aliran yang termal lapisan batas mengembangkan dan mencapai pusat tabung disebut wilayah termal entri, dan panjang wilayah ini disebut panjang masuk termal. Wilayah di mana aliran adalah keduanya hydrodynamically (profil kecepatan sepenuhnya dikembangkan dan tetap tidak berubah) dan thermally (profil berdimensi suhu tetap tidak berubah) dikembangkan disebut wilayah sepenuhnya dikembangkan.