Engineering Answers

A two-stage, double-acting compressor is to deliver 90 lb/min of air from 14.3 psia and 90 ̊F to a final pressure of 185 psia. The normal barometer is 29.8 in. Hg and the temperature are 80 ̊F. The pressure drop in the intercooler is 3 psi and the temperature of the air at the exit of the intercooler is 90 ̊F, the speed is 210 remand pV1.34 =C during compression and expansion. The clearance is 5% for both cylinder. The temperature of the cooling water increases by 18 ̊F. Find: a) The volume of free air b) The discharge pressure of the low-pressure cylinder for minimum work, c) The temperature at discharge from both low pressure and high-pressure cylinders d) The mass of cooling water to be circulated about each cylinder and through the intercooler e) The work f) If, for the low-pressure cylinder, L/D = 0.68 and if both cylinders have the same stroke, what should be the cylinder dimensions?

What is the voltage transfer function of this buffer circuit?

The falling rate portion of the drying time for a particle of skim milk begins at the critical moisture content of 25%, and the final moisture content is 4%. The air used for drying is 120°C and was heated from ambient air of 20°C and 40% RH. The particle size at the critical moisture content is 20 microns, and the specific heat of the product solids is 2.0 kJ/kg K. The mass diffusivity for water within the product particle is 3.7 x 10-12 m2/s, and the density of the product particle is 1150 kg/m3. If the equilibrium moisture content for the product is 3.5%, estimate the time for the falling rate portion of drying. 

b. If 5000 m3/min of heated air is needed for product drying, determine the thermal energy needed to heat the air to 120°C. 

A fluid at 0.7bar occupying 0.09m^3 is compressed reversibly to the pressure of 3.5bar according to the law pv^n=C. The fluid is heated reversibly at constant volume until the pressure is 4bar, the specific volume is then o.5m^3/kg. A reversible expansion according to the law pv^2=C restores the fluid to its initial state. Sketch the graph and calculate the mass of the fluid present, the value of the n in the first process, and the network of the cycle.

A field is in the form of a regular pentagon. The direction of the bounding sides was surveyed with the assumed meridian 6° to the right of the true north and south meridian., the bearing of one side AB is N 40°57’ W. Compute the bearing of CD

a piston-cylinder device 0.5 kg of carbon dioxide is compressed from 0.3 to 0.1 m3

. During

the process, the pressure and volume is related by P = aV-2

, where a = 8 kPa.m6

. Calculate work

transfer, change in internal energy and heat transfer during the process. (Take isobaric heat

capacity, cp = 0.847 kJ/kgK).

A fuel contains by mass 88% C,H, 8% ash (silica). Calculate the stoichometric air

A heatpump is to be used to heat a building during the winter. The building is estimated to be looosing heat at a rate of 136000kj/hr when the outside temperature drops to 5°c. Determine the minimum power required to drive the heatpump unit for this outside temperature

A heat engine has a combustion chamber where 450KW of heat is generated every second. Out of this, 55% is successful transferred to the boiler fluid while the rest is lost in tbe exhaust of the heat added in the boiler, 140KW is converted to work in the turbine while the turbine supplies 55KW to the pump. Determine the efficiency of the heat engine