This work aims to model and simulate an absorption cooling system using solar flat- plate receiver with water lithium bromide (li.Br-H2O) mixture as a working fluid, and to select the optimum type for absorption cooling system, which have suitable application in Iraq. Weather conditions for Erbil city have been selected. Coefficient of performance (COP) for a single, double (series and parallel), half and triple effect of an absorption cooling system are calculated and optimized. COP Prediction, hot water temperature, and the rate of heat transfer have been simulated and represented by using TRNSYS and EES programs. Active area of the solar flat-plate receiver is calculated and optimized for five suggested areas of (140, 150, 160, 170, and 180 m 2). Average heating load, average daily - radiation and cooling load for summer months (June, July, August, and September) have been calculated. The results indicated that, the superior type of the four absorption-cooling systems is a single effect, which has COP 80% at generator temperature of (81 °C). Also the results indicated that the optimum area of solar flat-plate receiver was 160 m2 which has achieved the maximum capacity of cooling power and consumed capacity in the generator (50, and 62.5) kW respectively. I think, according to the previous studies , the current work is the first in Iraq because it approved that, single effect type is an efficient and more relevant type for good working under Iraqi climate by using solar flat–plate receiver and suitable to apply it experimentally in a wide range.

Solar flat-plate receiver --- An absorption cooling systems --- TRNSYS --- EES programs.

An Experiment was conducted to study the effect of the spray nozzle and operating pressure on weeds control accompanying with wheat crop, at the experimental field of the College of Agriculture /University of Baghdad, about 20 km west of the Baghdad city during the winter season of 2013-2014 . pallas45 herbicide, three levels of operating pressure included 2.3 and 4 bar represented main plot, and three types of spray nozzles included Hollow Cone Nozzle, Flat fan 11004 Nozzle and Turbo TT11005 Nozzle which represented sub plot were used in this studyThe indicators that were studied in this experiment included: droplet size in terms of volumetric median diameter (VMD) (micron), coverage (drop / cm 2), the percentage of weed control after 4 weeks of application (%), and wheat yield (t / ha). The experiment was designed according to split plot design under randomized complete block design (RCBD) with three replications. The least significant differences (L.S.D) at 0.05 levels to compare the means of treatments were used in this study. The results can be summarized as followTurbo TT11005 nozzle was superior on Flat fan 11004 nozzle and Hollow cone nozzles sequentially characteristics: volume median diameter (VMD) 353.72 micron, the percentage of the weed control 82.95%, wheat crop 4.26 t / ha either coverage, hollow cone nozzle where superior on the Flat fan 11004 nozzle and Turbo TT11005 nozzle sequentially, 167.28 drop / cm 2 . Increasing the operating pressure from 2 bar - 3 bar - 4 bar caused decreasing in the volume median diameter (VMD) 166.33 micron, and to increasing in the coverage 169.89 drop / cm 2, the percentage of weeds control, 76.29%, wheat crop 4.21 t / ha. Overlap between the nozzle type and pressure was significant effect. the overlap between Turbo TT11005 nozzle and (4 bar) pressure was superior in the percentage of weed control 96.25%, wheat crop 4.35 t / ha. while the overlap between Turbo TT11005 nozzle and (2 bar) pressure was superior in volume median diameter, 412.50 micron. The overlap between Hollow Cone Nozzle with (4 bar) pressure was superior in the coverage217.66 drop / cm 2 .

اجريت تجربة حقلية بهدف دراسة تأثير فوهة الرش وضغط التشغيل في مكافحة الادغال المرافقة لمحصول الحنطة, في حقول التجارب التابعة لكلية الزراعة / جامعة بغداد التي تبع20 كم غربي مدينة بغداد خلال الموسم الشتوي 2013-2014. استخدم في التجربة المبيد الانتخابي ( (Pallas45وثلاثة مســـــتويات من الضغط التشغــــــيلي هي 2 و 3 و 4 بار مثلت الالواح الرئيســـــــة, وثلاثـــــــــة أنــــــواع مـــن فوهــــات الـــــرش Hollow Cone NozzleووFlat fan 11004 NozzleTurbo TT11005 Nozzleمثلت الالواح الثانوية.تمت دراسة بعض مؤشرات الاداء الفنية لالة الرش وشملت القطر الوسيط الحجمي (VMD) لقطرات الرش (مايكرون) و التغطية (قطرة/سم2) والنسبة المئوية لمكافحة الأدغال بعد 4 أسابيع من المكافحة % و حاصل حبوب الحنطة (طن/هكتار). نفذت التجربة باستخدام نظام الألواح المنشقةSplit Plot Designتحت تصميم القطاعات العشوائية الكاملة وبثلاثة مكررات واستخدم اقل فرق معنوي (LSD) تحت مستوى احتمالية0.05 لمقارنة متوسطات المعاملاتوتلخصت النتائج بأنه تفوقتفوهةTurbo TT11005 NozzleعلىفوهاتFlat fan 11004NozzleوHollowConeNozzleبالتتابعبصفات: القطرالوسيطالحجمي (VMD) فبلغ 353.72 مايكرون, النسبةالمئويةلمكافحةالادغالفبلغت 82.95 %, حاصلالحبوبفبلغ 4.26 طن / هكتاراماصفةالتغطيةفقدتفوقتفيهافوهةHollowConeNozzleعلىفوهاتFlat fan 11004 NozzleوTurbo TT11005 Nozzleبالتتابعفبلغت 167.28 قطرة / سم2. أدتالزيادةفيمعدلالضغطمن 2 بارالى 4 بارإلىنقصانقيمةالقطرالوسيطالحجمي (VMD) فبلغت 166.33 مايكرونوإلىزيادةقيمةكلمنالتغطيهفبلغت 169.89 قطرة / سم2 والنسبةالمئويةلمكافحةالأدغالفبلغت 76,29 % وحاصلالحبوبفبلغ 4.21 طن / هكتار. كانللتداخللثنائيبيننوعالفوهةوالضغطتأثيرمعنوي. فتفوقتمعاملةالتداخلبينفوهةTurbo TT11005 Nozzleوالضغطالثالث4 باربصفاتالنسبةالمئويةلمكافحةالادغالفبلغت 96.25 %, حاصلالحبوبفبلغ 4.35 طن / هكتار. بينماتفوقتمعاملةالتداخلالثنائيبينفوهةTurbo TT11005 Nozzleوالضغطالاول 2 باربصفةالقطرالوسيطالحجميفبلغ 412.50 مايكرون. اماصفةالتغطيةفقدتفوقتفيهامعاملالتداخلالثنائيبينفوهةHollow Cone Nozzleمعالضغطالثالث4 بارفبلغت 217.66 قطرة / سم2.

volume median diameter --- vmd --- coverage --- wheat crop --- spray pressure --- Turbo TT11005 Nozzle --- Flat fan 11004 Nozzle --- Hollow Cone Nozzle --- القطر الوسيط الحجمي vmd --- ، التغطية --- حاصل الحنطة --- ضغط الرش --- Hollow Cone Nozzle --- Flat fan 11004 Nozzle --- Turbo TT11005 Nozzle.