Nkyerɛase ne nkyekyem a ɛfa ɔhyew a wɔde sesa nneɛma ho .

Sɛnea ɛbɛyɛ a wobenya ɔhyew a ɛkɔ so yiye no, ɔhyew a wɔde sesa nneɛma yɛ afiri a ɛpaapae media mu denam afasu a ɛyɛ den so ma ɔhyew a ɛkɔ so yiye. Ebia afasu a ɛyɛ den bɛtetew saa nsɛm ho amanneɛbɔ yi mu de ahwɛ ahu sɛ ɛne wɔn ho wɔn ho nhyia, anaasɛ ebia ɛne wɔn ho wɔn ho di nkitaho tẽẽ. Wɔde ɔhyew sesa di dwuma kɛse wɔ mfuw pii mu, te sɛ ahunmu ɔhyew, frigye, mframa a wɔde yɛ adwuma, anyinam ahoɔden mfiri, nnuru a wɔde yɛ adwuma, ne nea ɛkeka ho Ɔhyew a wɔtaa de sesa nneɛma ne mprɛte ne akorade ne tube ahorow. Bio nso, ɔhyew a wɔkora so ɔhyew sesa, adiabatic ntwahonan mu ɔhyew sesa, mprɛte-fin ɔhyew sesa, nsu a wɔde sesa ɔhyew, ɔhyew a wɔde yɛ ɔhyew a wɔsan nya, ne ɔhyew a wɔde sesa nneɛma a wɔapetepete so. Mpɛn pii no, ɔhyew a wɔde sesa nneɛma no nkyekyem no gyina nsu abien a ɛwɔ nnwinnade no mu no nsu a ɛsen fa so no so. Nneɛma abiɛsa a ɛwɔ mu no yɛ nsu a ɛsen, counterflow, ne crossflow a ɛne ne ho di nsɛ.