1 Pertemuan 10 Sistem pengukuran panas Matakuliah: H0262 / Pengukuran dan Instrumentasi Tahun: 2005 Versi: 00 / 01
2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Mahasiswa dapat menjelaskan sistem pengukuran panas
3 Outline Materi Materi 1 : Pendahuluan Materi 2 : Sistem Pengukuran radiasi panas Materi 3 : Detector dan elemen signal conditioning Materi 4 : Sistem Pyrometer Materi 5 : Infra red Gas Analyzer
Sistem Pengukuran Panas 1.Pendahuluan Mekanisme conduction convection radiation W = U A ( T – T F ) Dimana U =koefisien heat transfer : Wm -2 0 C -1
5 d = sensor diameter = fluid velocity = fluid density = fluid viscosity c = fluid heat capacity k = fluid thermal conductivity N U = ( Re, Pr ) dimana Nusselt Nu = Ud / k Reynolds Re = d / Prandtl Pr = c / k
6 Sistem pengukuran radiasi panas Gb 10.1 Thermal radiation measurement system
7 Total power by black body Stefan`s law : V TOT = 0 C 1 d 5 [ exp (C 2 / T ) – 1 ] = T 4 W cm -2 dimana = 5.67 x W cm –2 0 K -4 konstanta Stefan - Boltzman
8 Gb 10.2 Power spectral density by black body radiation
9 Detector dan elemen signal conditioning Karaktersitik performance detector : sensitivity K D time constant wavelength response Noise Equivqlent Power ( NEP) D * = ( S/N ) ( A f ) 0.5 p cm Hz 0.5 W -1
10 Gb 10.3 various detector
11 Pyrometer system two colour pyrometer system : R (T) = ( ) 5 exp C2C2 T ( - ) 1 1
12 Gb 10.4 sistem pengukuran temperatur radiation
13 Infra Red Gas Analyzer T ( ) untuk acetylene ( C 2 H 2 ) dan CO A ( ) = 1 - T ( ) More power at 5 m will reach detector from the. sample cell than from the reference cell. The amount energy at 5 m absorbed by each section will be different.
14 Gb 10.5 non dispersive IR analyzer dan karakteristik transmisi.
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