Pemodelan dan Simulasi Pencairan Gas Alam dengan Persamaan Keadaan Peng Robinson

Gas alam merupakan energi yang ramah lingkungan dibandingkan batubara dan minyak bumi. Pencairan gas alam memudahkan pengangkutan pada jarak jauh. Tujuan pemodelan dan simulasi pencairan gas alam ini yaitu mengetahui pengaruh temperatur dan tekanan pada masukan kompresor. Simulasi dilakukan secara statis dan dinamis. Metode simulasi pencairan gas alam menggunakan perangkat Matlab dengan persamaan keadaan Peng Robinson dan aturan campuran (mixing rules). Pemodelan statisdilakukan pada temperatur masukan gas alam 298 K dan tekanan 20 atm. Hasil simulasi menunjukkan gas alam mengalami pencairan pada siklus kedua. Temperatur gas alam siklus pertama mencapai 182 K sedangkan kedua 112 K. Pemodelan dinamis memvariasikan temperatur masukan kompresor pada komposisi gas alam tetap dan variasi komposisi gas metana pada temperatur masukan kompresor tetap. Hasil menunjukkan semakin tinggi temperatur masukan kompresor, semakin tinggi temperatur keluaran kompresor akhir dan throttling valve. Pada variasi komposisi gas metana, semakin besar komposisi gas metana maka semakin rendah suhu keluaran kompresor

Improved Service Learning Outcomes Using D'volleyball Learning Application

This study aims to determine the improvement of service learning outcomes for high school students using the D'Volleyball Learning Application learning media at SMA N 1 Indralaya Utara. This learning application can be accessed via the link https://play.google.com/store/apps/details?id=com.dvolleyball.learning or on the play store by searching for D'Volleyball Learning Application. This D'Volleyball Learning Application contains various features regarding volleyball game material, assignments, learning videos, and assessments. This study uses a classroom action research method, with the number of research subjects as many as 22 class XII students at SMA N 1 Indralaya Utara. This research uses the type of classroom action research conducted in two cycles. Data collection techniques used in this study were tests and observations. Each cycle has four stages, namely planning, implementation, observation, and reflection. The research subjects were 22 students including 10 female students and 12 male students. The results in this classroom action research obtained data on the initial conditions or pre-cycle of 36.4% of students completed, and 63.6% incomplete, then the results of the first cycle of student learning outcomes amounted to 63.6% with complete criteria, and amounted to 36.6% did not complete, then the results of the research in cycle 2 increased by 36.6% so that all students completed learning in cycle 2. So the conclusion is that the D'Volleyball Learning Application can improve the service learning outcomes of volleyball for class XII students at SMA N 1 Indralaya Utara