1. Área de Instrumentación INSTITUTO DE ASTROFÍSICA DE CANARIAS J. Fuentes and D. Sosa Instituto de Astrofísica de Canarias NAHUAL THERMAL MODEL

2. Área de Instrumentación J. Fuentes and D. Sosa Instituto de Astrofísica de Canarias 2 Dewar Cold Shield Dewar Electro Polished AlMLI 20 layer Qr 1 =82 W Qr 2 =96 W Qr 3 =111 W Qr 1 =27 W Qr 2 =31 W Qr 3 =36 W Qr i = Q(T i )‏ T 1 =271 KT 2 =281.5 K T 3 =292 K MLI Combinations without Floating Shield Text 77 K Text 77 K Cold Shield

3. Área de Instrumentación J. Fuentes and D. Sosa Instituto de Astrofísica de Canarias 3 CS Dewar FS Electro Polished Al MLI 20 layer 1 2 3 4 CS Dewar FS CS Dewar FS CS Dewar FS Qr 1 =58 W Qr 2 =67 W Qr 3 =78 W Qr 1 =17 W Qr 2 =20 W Qr 3 =23 W Qr 1 =24 W Qr 2 =28 W Qr 3 =32 W Qr 1 =12 W Qr 2 =14 W Qr 3 =16 W Qr i = Q(Text i )‏ T ext 1 =271 K T ext 2 =281.5 K T ext 3 =292 K Text 77 K MLI Combinations with Floating Shield FS = floating shield CS = Cold Shield

4. Área de Instrumentación J. Fuentes and D. Sosa Instituto de Astrofísica de Canarias 4 wirespipes window rad trusses 10 W2 W15 W 3 W 20 W Case 2 Text = Tnom = 281.5 K 20 W radiation Dewar AS CS 281.5 K 275 K 77 K LN2 Vessel for 24 hr lasting time: 27 L conduction load = 27 Wradiation load = 23 W Heat Map

5. Área de Instrumentación J. Fuentes and D. Sosa Instituto de Astrofísica de Canarias 5 wirespipes window rad trusses 10 W2 W15 W 3 W 14 W Case 4 Text = Tnom = 281.5 K 14 W radiation Dewar AS CS 281.5 K 277 K 77 K LN2 Vessel for 24 hr lasting time: 24 L conduction load = 27 Wradiation load = 17 W Heat Map