Visualisasi Aliran Udara pada Kotak Konveksi Udara Menggunakan Adaptive Finite Element Method

Sayahdin Alfat; Abdin Abdin; Rosliana Eso

doi:10.17509/wafi.v5i2.28761

Authors

Sayahdin Alfat Jurusan Pendidikan Fisika, Universitas Halu Oleo, Indonesia
Abdin Abdin Jurusan Pendidikan Fisika, Universitas Halu Oleo, Indonesia
Rosliana Eso Jurusan Pendidikan Fisika, Universitas Halu Oleo, Indonesia

DOI:

https://doi.org/10.17509/wafi.v5i2.28761

Keywords:

Aliran udara, Adaptive Finite Element Method, persamaan Rayleigh-Bernard, kotak konveksi

Abstract

Peristiwa aliran udara pada kotak konveksi menjadi penting untuk dipahami. Selain metode eksperimen, metode numerik menjadi salah satu pendekatan yang realistis dan mudah serta murah. Secara garis besar, studi ini akan menampilkan transfer panas dan aliran udara pada kotak konveksi menggunakan Adaptive Finite Element Method dan profil temperatur serta kecepatan udara di beberapa titik pada kotak konveksi. Simulasi ini mengadaptasi persamaan Rayleigh-Benard sebagai persamaan pembentuk aliran dan Metode Karakteristik sebagai metode diskritiasi waktu. Secara keseluruhan, penentuan solusi numerik berupa transfer panas dan aliran fluida menggunakan FreeFEM++. Parameter waktu yang digunakan selama perhitungan, seperti: M_t= 10^-3 dan t_max = 10³ . Beberapa hal yang menjadi catatan dari penelitian ini sebagai berikut; (1) profil temperatur berbeda di setiap titik pada kotak konveksi, temperatur tertinggi dijumpai di sekitar sumber panas sebesar 100^oC dan terendah berada di permukaan ujung tabung yakni 20^oC. (2) Aliran udara masuk melalui sisi kiri tabung dan ke luar melalui sisi lainnya. Ini menyebabkan kecepatan rata-rata di kedua tabung tersebut sama dan bernilai u_y : 10.2 pada saat t 2 0.06.

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