Indian Agricultural Research Institute (IARI) 2007 Post Graduate Diploma Natural Resources Indian Forest Service Agricultural Engineering - II - Question Paper

PAPER - II : part A
1. Write short notes, not exceeding 150 words each, on any 4 of the subsequent :
(a) Radiator Pressure cap. (10)
(b) Starting aids used in diesel tractors. (l0)
(c) Paddy drum seeder. (10)
(d) Savonius wind rotor. (10)
(e) Solar photo-voltanic cells. (10)

2. (a) Draw P-V diagram of an ideal diesel cycle indicating the various events. Mark the swept. quantity and clearance quantity in the diagram. Also draw an true P-V diagram and discuss the causes for its deviation from the ideal cycle for a 4-stroke cycle engine. (15)

(b) With the help of a diagram, discuss the working of a conventional differential as used in the rear wheel driven tractors. What is the function of a differential lock? (15)

(c) discuss with a diagram the working of bypass kind lubricating oil filtering system as adopted in modern tractor engines. (10)

3. (a) discuss the working of a power operated flywheel kind forage chaffcutter. How is power transmitted to the feed rolls seven How do you determine the theoretical capacity of the chaffcutter? (15)

(b) What is producer gas ? With a schematic diagram discuss the working of a down draft kind gasifier. (10)

(c) With a neat sketch, discuss the working of a tractor mounted hydraulic sprayer. How does a hollow cone nozzle differ from the solid cone nozzle? How do you determine the field capacity of the sprayer ? (15)


4. (a) If a farmer can hire a 7.5 kW power tiller with operator for Rs. 85 per hour for tilling operation, how many hours per year must he operate to justify the purchase of this power unit? Take initial cost of powertiller with rotavator Rs. 1,20,000; useful service life 15 years diesel fuel consumption one five liters/hour; and operator’s wages Rs. 75 per day. presume any other data if needed. (15)

(b) discuss the procedure to choose a suitable size of electric motor for running a centrifugal pump for lifting water from shallow well. (10)

(c) Draw the sectional view of a fixed dome kind biogas plant and show the various components. compute the needed size of digester for a three in3 capacity biogas plant using retention period as 50 days. (15)

part B
5. Write short notes, not exceeding 150 words each, on an low of the subsequent :
(a) Homogeization of milk (10)
(b) Extraction of oil from rice bran (10)
(c) Strain gauge torque sensor (10)
(d) Vapor compression refrigeration system. (10)
(e) Computer memory. (10)

6. (a) compute the amount of moisture evaporated from 100 kg of paddy grain from drying it from an initial moisture content of 22 per cent (wet basis) to final morsture content of 14 per cent on wet basis. (10)

(b) discuss the working of an absorption kind hydraulic dynamometer. How can this dynamnometer be used to measure the brake power of an engine ?

(c) elaborate the desirable qualities of packaging materials for foods? provide most commonly used packaging materials, 1 every for milk, butter, baked foods and tea and write their properties. (15)

7. (a) What is deep bed drying ? discuss with a diagram the process of drying paddy grains using this technique. (10)

(b) With a block diagram, discuss the generalised data acquisition system. elaborate the factors that decide the configuration and sub systems of data acquisition system ? (15)

(c) What is milk sterilisation ? How is it various from pasteurization? With a flow chart, discuss the preparation of in-bottle sterilized milk. (15)

8. (a) discuss the production of milk powder using a spray dryer. Compare the milk prepared from whole milk powder with the fresh milk in terms of shelf life and nutritive value. (15)

(b) elaborate thermocouples? How can it be used to measure the temperature of a hot body ? Write 2 most commonly used materials for thermocouples and provide their temperature ranges. (15)

(c) discuss the working of a bucket elevator for handling small grains. How do you determine the theoretical power requirement of a bucket elevator? (10)

Earning:   Approval pending.