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Heat TransferUISI For internal use only 1EM52013 Heat TransferDepartment of Engineering ManagementUNIVERSITAS INTERNASIONAL SEMEN INDONESIA

OKKY PUTRI PRASTUTI, S.T, M.T

2(HEAT TRANSFER)Analisa Konduksi Kondisi Steady State

Untuk persoalan perpindahan panas Steady State, tak ada generasi, area konstan

= Konstan

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3(HEAT TRANSFER)Contoh SoalThe diagram shows a conical section fabricated from pyroceram. It is of circular cross section with the diameter D = ax, where a = 0.25. The small end is at x1 = 50 mm and the large end at x2 = 250 mm. The end temperatures are T1 = 400 K and T2 = 600 K, while the lateral surface is well insulated. Conductivity of pyroceram is 3.46 W/m.K

Derive an expression for the temperature distribution T(x) in symbolic form, assuming one-dimensional conditions. Sketch the temperature distribution.Calculate the heat rate q, through the cone.T1T2x1x23

4(HEAT TRANSFER)SolutionDiketahui : Diameter cone D = ax, dimana a = 0.25. K pyroceram = 3.46 W/m.K

Ditanya : Distribusi temperature T(x) dan Laju perpindahan panasT1 = 400 KT2 = 600 KX1 = 0.05 mX2 = 0.25 mqxAsumsi :Kondisi steady stateKonduksi satu dimensi ke arah sumbu xTidak ada generasi panasProperti konstan4

5(HEAT TRANSFER)Solution contAnalisis :

Karena panas konduksi terjadi pada kondisi steady state, tidak ada generasi panas, maka laju perpindahan panas qx konstan tergantung oleh x. Hukum fourier dapat digunakan untuk menentukan distribusi temperatur.

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7(HEAT TRANSFER)Thermal Conductivity2. Subsitusikan nilai-nilai yang sudah diketahui dalam soal :

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8(HEAT TRANSFER)Pembahasan Tugas8

9(HEAT TRANSFER)Perpindahan Panas Konduksi dan Konveksi Secara SimultanKOEFISIEN PERPINDAHAN PANAS MENYELURUH (OVERALL HEAT TRANSFER COEFFICIENT, U)Adalah merupakan aliran panas menyeluruh sebagai hasil gabungan proses konduksi dan konveksi. Koefisien perpindahan panas menyeluruh dinyatakan dengan W/m2.0K (Btu/h.ft2.oF) 9Perpindahan Panas Konduksi dan Konveksi Bidang Datar

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Suatu bidang datar, salah satu sisinya terdapat fluida panas (T1) dan sisi lainnya terdapat fluida yang lebih dingin (T4).10

11(HEAT TRANSFER)Perpindahan Panas Konduksi dan Konveksi Bidang Silinder

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12(HEAT TRANSFER)SoalSaturated steam at 267oF is flowing inside in. Steel pipe having an ID of 0.824 in and an OD of 1.050 in. The pipe is insulated with 1.5 in of insulation on the outside. The convective coefficient for the inside steam surface of the pipe is estimated as hi = 1000 btu/h.ft2. 0F, and the convective coefficient on the outside of the lagging is estimated as ho = 2 btu/h.ft2. 0F. The mean thermal conductivity of the metal is 45 W/m.K or 26 btu/h.ft. 0F and 0.064 W/m.K or 0.037 btu/h.ft. 0F for the insulation.

Calculate the heat loss for 1 ft of pipe using resistances if the surrounding air is at 800F.Repeat, using the overall Ui based on the inside area Ai.

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13(HEAT TRANSFER)A gas at 450 K is flowing inside a 2in steel pipe, schedule 40. The pipe isinsulated with 51 mm of lagging having a mean k=0.0623 W/m.K. The convective heat-transfer coefficient of the gas inside the pipe is 30.7 W/m2.K. And the convective coefficient on the outside of the lagging is 10.8. The air is at a temperatue of 300 K.Calculate the heat loss per unit length of 1 m of pipe using resistances.Repeat, using the overall Uo based on the outside area Ao.

2. Water at an average of 700F is flowing in a 2-in steel pipe, schedule 40. Steam at 2200F is condensing on the outside of the pipe. The convective coefficient for the wter inside the pipe is h=500 btu/h.ft2.F and the condensing steam coefficient on the outside is h=1500.Calculate the heat loss per unit length of 1 ft of pipe using resistancesRepeat, using the overall Ui based on the inside area Ai.Repeat, using Uo13

14(HEAT TRANSFER)THANK YOU14