Temperature rise of SVD2 IR beampipe during single beam study

Temperature rise of SVD2 IR beampipeduring single beam study

Samo Stanič, SVD Meeting 　 2003/10/30

Single beam study

LER Imax=1A, imax=0.84 mA 　 nb ＝ 1187 bunches(1 train, fill pattern 10x4+1x5)

HER Imax=0.6A, imax=0.805 mA 　 nb ＝ 745 bunches (16 trains, fill pattern 10x4+1x5, gap 120 buckets)

HOM power estimate in Be

PHOM = kl I2 / (fb nb) = kl i2 nb / fb

fb = 100 kHz kl (Be) = 0.01-0.02 V/pC (ABCI est. for BL=6mm)

Pgen(LER)= 85-170W Pgen(HER) = 50-100WPmax(LER)= 4-9W Pmax(HER) = 2-5W (assuming max 5% goes into heat)

SVD2 IR beampipe temp. sensors

6 sensors on Be

4 sensors on manifolds

7 sensors in BWD(incl. 1 on and 1 behindCu Cooling block)

8 sensors in FWD(incl. 1 on and 1 behindCu Cooling block)

24 7

On cooling block

On manifold

On Be

Behind cooling block

RTD Around the manifold

RTD under BWD mask

RTD behind BWDCu block

RTD on Be staggered in phi(2 are hidden)

Locations of temp. sensors on the beampipe:full phi and z coverage

We know exact temperatures of paraffin before and after Be(in the both manifolds)

T(I) =Tconst +dT(I)

T(ILER)= 0.2+0.3 I2T(IHER)= 0.2+0.6 I2

dT(ILER= 1A)=0.3 deg dT(ILER=1.8A)=1.0 deg dT(ILER=2.5A)=1.9 deg

dT(IHER=0.6A)=0.2 deg dT(IHER=1.2A)=0.9 deg dT(IHER=1.5A)=1.4 deg

Quadratic fit of the temperature difference betweenin- and out-flowing paraffin

Heat deposit in Be:

dTLER=0.3 deg dTHER=0.2 deg

dm/dt=0.88kg/min (1.1l/min) Cp=2300kJ/kg/K

P=dm/dt * Cp * dT Pmeas(LER) = 10W P[W]=34 * dT [K] Pmeas(HER) = 7W

If we extrapolate dT(I):

Pext(ILER=2.5A) = 65W Pext(IHER=1.5A) = 50W

The fit of present data is close to design value for Be (100W)

Single beam study with larger currents would help…

Be pipe LER side(paraffin inlet)

Tmp(11): beampipez=101mm from IP

LER 1A/HER 0.6AdT=0.28 degLER 1.8A/HER 1.2AdT=0.72 deg LER 2.5A HER 1.5AdT=1.19 deg

Be pipe HER side(paraffin outlet)

Tmp(28): beampipez=-54mm from IP

LER 1A/HER 0.6AdT=0.5 degLER 1.8A/HER 1.2AdT=1.8 deg LER 2.5 HER 1.5AdT=3.17deg

Hot spot LER side

Tmp(7): beampipez=160mm from IP(after Cu cooling block)

LER 1A/HER 0.6AdT=3.6 degLER 1.8A/HER 1.2AdT=12.5 deg LER 2.5 HER 1.5AdT=22.1 deg

Hot spot HER side

Tmp(24): beampipez=-105mm from IP(after Cu cooling block)

LER 1A/HER 0.6AdT=1.8 degLER 1.8A/HER 1.2AdT=10 deg LER 2.5 HER 1.5AdT=18.5deg