Npre 402 Exams

— A \ NPRE 402 Nuclear Power Engineering Fall 2014, First Midterm el Please answer all questions. Use the back of the answer sheet as needed. \ Name: ©\\e oo MeAcs Question 1; 3 A fusion process uses the ;:B" fusion reaction producing a C'? nucleus in its excited state. This excited C'? nucleus decays to Be® and He®. Be® within 10™ sec further decays into two more He nuclei. This is the only nuclear-energy releasing process in that releases fusion energy and helium nuclei, but no initial neutrons. m(,H') =1.0078250 amu, m(,B") = 11.0093055 amu, m(, He') = 4.0026032 amu 1 amu =931.481 MeV ] t v et 98 o Q= 93106 [(t o5 oszosh) Y by By oC" = Rels, Het TS es2 0 = (3 0ot03n)] ETBEE T et ety g = - ? + ? H e \ v — 747 > 2 (,u *6%”9\31\49.“-! Question 2: Compute the thicknesses of a Pb shield that would attenuate a beam of 1 MeV gamma rays with a build-up factor of B = 2, to one billionth of its initial strength, given that its linear attenuation coefficients at 1 MeV is 0.8 cm™., S facenesS = Ux107! e | Question 3: The isotope g, Thallium®® has a half life @nd c b&ased-flman@;hnology power source device. It decays through beta emission into g, with a ching ratio of 97.Dpercent with an average decay energ also e_c_@&through electron capture to goHg™"* with a branching ratio percent with a decay energy 0£-0.347 MeV. N Calculate the energy release per decay event in [MeV/disintegration] Calculate its total specific activity in [Becquerels / gm]. Calculate its total specific activity in [Curies / gm]. Calculate the specific power generation in [Watts(th) / gm]. For a 100 Watts of thermal (Eower in a Radioisotope Heating Unit (RHU) power generator, how many grams of g, Thallium®* are needed? 6. After 3.78 years of operation, what would its power become? Use: 1 MeV/sec = 1.602x10™ Watts, A, = 0.602x10* [nuclei/mole], 1 Curie = 3.7x10'"° Bq. L E = 001 (p 16U Mev) + 6026 (0. 30 Mel) 40191007 MeV/dsimetiion v G B9 (1) N - g S G ey [ MW \T\ 0" o fi‘ \G x\ %j@ 31 NbxI10P R \ core. | X =~ L\(O \—\ \ l q 3x1Q° B , >Te ¢ m —> on o\

N 2 N .k\'w ,_’LX_‘\"\) K {q‘\ L ) NPRE 402 Nuclear Power Engineering Spring 2015, First Midterm Please answer all questions. Show details of your calculations. Use the back of the answer sheet if needed. No extra sheets are {. 5- Name; Ta"}\o‘ 427?5, } 5 P, P / v Question 1 »\% The isotope g Thallium™ has a half-life o{3.78 yearsyind may be used as a nanotechnology and Micro Electro NG Mec?oa}nigal Systems (MEMS) power source. T{i§@ pure beta emitter without gamma rays emission. It decays into N\“\ anb witha branchmgzgi\tio of 97.1 percent with a decay energy of 0.764 MeV/disintegration. It also decays through N~ electron capture to gHg™ with a branching ratio of 2.9 percent with a decay energy of 0.347 MeV/disintegration. %4 P . Calculate the average energy release per decay event in [MeV/disintegration] A 3. Calculate its total specific activity in [Curies/gm). 1. " 4 Calculate the specific thermal power generation in [Watts(thygm]. Q“‘/ M /8. For a 100 Watts of thermal power in a Radioisotope Heating Unit (RHU) power generator, how many grams of 1e nghalliumzo‘ are needed? A \ /V After 3.78 years of operation, what would its thermal power become? By 7. The Cassini space probe to Saturn needs an electrical supply of 1 kWe ( kiloWatt(e)) of power. If it were powered 2. Calculate its total specific activity in [Becquerels/gm]. ( g p-oe by a Radioisotope Thermoelectric Generator (RTG) operating at a conversion efficiency of 50 percent, what would be /PV the needed amount of 8,"I'ha1131ium2°4? N N N Use: 1 MeV/sec=1.602x10" Watts, A,=0.602x10* [nuclei/mole], 1 Curie=3.7x10'° Bq. 752 MeV/ 45 tamtrer { M 1\a= ( a7l5(o.7e‘{ Mev /iy aton) x (,024Y0-347 MV /I;s:wkwi'?g) =(¢=0.7>2 ol j v R 23 3 ' ¢ INT, -3 P A5 Mags| 2 v Omf01C 180t s A= o). (6-0210 ) 2\, 72 10 B¢/y™ f\ ‘) n- Ve Vdag | \ne Lmin (\.M?y\(fllg) (20‘4 {)) M 33, | | Gre k —> ‘/Q_‘EM ?)) . 72x0 m {"‘3 740 0" %T, = Lli_és (uies [om fw A fusion process uses the gB“ fusion reaction producing a C'? nucleus in its excited state. This excited C'2 nucleus decays to Be® and He*. Be® within 10" sec further decays into two more He® nuclei. This is the only known nuclear- energy releasing process that releases fusion energy and helium nuclei, but no initial neutrons. m(,H") =1.0078250 amu, m(,B") =11.0093055amu, m(,He") = 4.0026032 amu , 1 amu =931 481 MeV 1. Balance the nuclear reactions. _ lbbm{(' 267$250,m, ¢ 11:0043059 amu) °<3 4. 00260R "”)l 2. Calculate the Q value of thg ggg@uggctinn.--- = 4 { o 1 12¢ i } ? +.B"> C '\& W ;sl ',‘,"(d . ‘5m:0.00“52°4 any C" - B+ ? | - i te | 6 . | W& Bty L Qeam @5‘_'{%] foev) B - ? + 7 8@1 v 4 | i - Ue « He | J 4 T T g (oot an¥asl 40K < 5 i . R 7T > 1 Wb AN Question 3 ,\_ g Write down the units of the following radiological quantities: Radiological Quantity Conventional System Unit SI System Unit Activity Ba X X g 5=t Absorbed Dose ? > ke =1 % ~ Using the law of radioactive decay calculate the fraction of the tritium isotépe (No-K(t)/No decaying into the He isotope. The half-life of tritum is 12.33 years. 11121233 5 N v 1 Y al A~ Within 1 year. N (_ (n(l)/ @0 D < Fo ,0,‘1‘\5 |- 0,055 W5 Muwye N_ -7 _ L5 = exp 2.3 9 ~*e 2. Within 12.33 years. ** M " \ N E) 50 hes J{,“V)“j Ne 5 A Wibin2466yers o () anw)): %05 1-%.-|0 : N N B} V Question 4 > %--‘”P(‘CP’\“)/D.SS\gf)éq.bé%')}ffu'0'25 | No ~ 0:75 s deau ){l 1. Assuming that heat rejection occurs at an ambient temperature of 20 degrees Celsius, estimate the Carnot cycle thermal efficiency of a PWR (Pressurized Water Reactor) operating at an average heat addition temperatures T, of 168 °C. 2. List 5 Engineered Safety Features (ESFs of the PWR concept 2. Conbol colls, cantmnmont ok +cotbnaunt sprag) WPCT (hipresivd caoban? g, LPCT (tnw pressume calant weet)) esidbal bl ool gt e clamngpt

D NPRE 402 Nuclear Power Engineering Fall 2014, Second Midterm Test | 6 Please answer all questions. Show or derive the equations that you use in your calculations and report the units and the detax} your calculations. Name: C1\©C | }\"‘C,erg [ g estion 1 ! W‘Q\’*&S The catalyzed DD reaction would occur in a second generation fusion reactor: . 2 v D'+ D' > 24 H'+4.03 MeV \D =+ ‘D — ,2 4 UOShe D+ D' %4 0 +327 MeV 'D”+\Dl_.;7_),\€5 3 1Mev D'+ I 5% n' + 17.6 MeV D+ He* >+ H' +183 MeV a. A reduction of the initial radius r, byafactq{ of 2. Q = QQ 2 < \y 1% 0:041 Al%M\/(n\q b. A reduction in the initial radius'x, by a fagtorof 10. ‘ = 0% Q:DQZQW# Question 2 1. Therred D@ ON g' E\etrao CoOGineA (C SL R \om QN of - A B 2 S05R0LS SR ON 5. no2zie e e85 What do the following acronyms stand for? PWR - D@ S0 20 bo(W N E TG ix— N BWR - Y\"z';/\ \WO JOsT e <t — .V-T' HTGR —‘T\\Q\'f\‘\\'r;(\‘\\'} w(*—( Lce UL f. r - \ \/ [ \ ANV UV N 1 Tl B LNIFBR - aungd \—\»\e:. Cui’\. { »:‘ N2 AN ) -\ " MSBI).\ ! 1 SOy 3(\‘6\_‘4‘ VoW Y G AT D e Question 3 ' The fuel consumption rate in a thermal reactor operating at a power level of P MWth is given by: consumption rate= 1.299 P [E—] day An executive at an electrical utility company needs to order n@q@;—g@) fuel from a mine. The utility operates a 1,000 MWe power plant operating at an overall thermal efficiency of 1/3 of the CANDU type using natural uranium. What is the ye‘grly amount in metric tonnes of: ) o T ; A 1. U consumed by the reactor? ("2 - | 20! (3000) = 3541 g/de o * I 1122409 e A 2. Natural uranium metal that the executive has to contract for with the mine in metric tonnes}er year as feedfo his nuclear unit? Note: 1 metric tonne = 1,000 kgs, the natural abundance of U** in natural uranium is 0.72 percent, ' ) O) C ,' '2"1‘1 < TN " fn = 1000,/ /3 = 3000 M Wi Mp=CR | W22405aiie 10188 24 g/ | X2 S : XC\TCDQ}(OM—% ‘(‘ \ A Stirling cycle engine using a radioactive isotope for space power applications operates at a hot end temperature of LA 650 °C and rejects heat through a radiator to the vacuum of space with a cold end temperature at 120 °C. Calculate its ideal Stirling cycle efficiency. ’ZOf“. RS o 10914 I T\—k ‘OLJO‘V'L"&

ki \ " Hefl.\«{g ~ 12’/) L 5{} " ’I/U f«gs (s (M ) g NPRE 402/ME 405, Nuclear Power Engineering 5 Spring 2012, Second Midterm Test Please answer all questions. Show or derive the equations that you use in your calculations and report the units and the details og calculati Nae &M}M i, o etion ,\[) uestion 1 Draw a line to match the following radiological quantities to their respective units on the right and left: Conventional System Radiological quantity SI System Unit L A Curie (Ci) ~ =3 Effective dose (dose equivalent) §<| ~Becquerel Bq) ey Zf#ing rem |~ Absorbed dose ~ Sievert (Sv) b e, l Aepted _rad Activity — £— — y (Gy) Apeprbed | Question 2 A sample of U™ is subjected to a neutron flux ¢ of 10" [neutrons /(cm?.sec)]. The microscopic scattering cross section o, for U™ with a density of p=19 [gm/cm’] is 8.9 barns. Avogadro’s number is 0.6 x 10** [nuclei/mole], 1 barn =10 cm o8 ; - : staw N =2 14 40, 022103l 1. Calculate the U™® number density, N, using the modified form of Avogadro’s law N = I; = s . (o. /b 2. Calculate the mgg)scoplc scattering CIOss s section Zg a3 3. Calculate the scattering mean free path As vad 4. Calculate the scattering reaction rate density R in [scattenngs (cm® = © N =/490e1? T B Question 3 O >\S - \{’L"l = 7’%31 i ~U} List 3 main processes for the isotopic separation and the enrichment of the uranium isotopes: q - 1. Zledeo Magn B SEpatton @ Q 9/< = 0 2. (&"\H \ i’@s’\ Lo “.—l. 3. Noat Pfoamé The fuel consumptlon in a thermal reactor operating at a power level of P MWth is given by: consumption rate= 1.299 P [;] Qura o VS (Engap fon - uln i An executive at an electrical utility company needs to order natural uranium fuel from a mine. The utility operates a 1,000 MWe pov plant operating at an overall thermal eflimency of 1/3 of the CANDU type using natural uranium. What is the yearly amount in me tonnes of: 7 ng f\ z MWl = (000 /"/3 = “Z3009 /‘/’WTH 1. U** consumed by the reactor? ZWetal that the executive has to contract for with the mine in metric tonnes per year as feed to his nuclear unit? Note: 1 metric tonne = 1,000 kgs, the natural abundance of U*® in natural uranium is 0.72 percent. O ’Y/' I.MK{ j MU/\(\ . ‘Lf/’m?’ -~ \‘uI 1 ’oq.‘dvv :\i\‘ r 7 Question 4 ' ”;‘ i N fowne List 3 ma%l processes of gamma rays interaction with matter: (Bfl'\ \) N AT\ ’\ } = | M’—\ ; 7 1. Photy elechmt x 00072 2. fhoto nicldr e 0 3. (qmplon Ccaflenny . A radiation shield is used to attenuate a gamma rays beam of initial mtens1ty I = 10° [photons/(cm” .sec)]. If the shield is made lead with a total attenuation coefficient at 1 MeV of Zt 0.771 cm™, what would be the ‘thickness, of the shield for attenuating tt gamma rays beam’s intensity to I(x) = 1 [photon/(cm” sec)] , cons1dermg an E_ponentufl attenuation of the beam, and a buildy factor of B=2? /(?\5 j 5 S C ,é_r x 1) -irx > K n S W2 1S, ]‘,b.g ‘yoS X = ’:O/,n\