Used to cool the cockpit of a refrigerated aircraft (33 tons of simple air refrigeration). The aircraft speed is 1278 km / hr, the temperature and pressure outside are -10°C and 0.4 bar, respectively, and the temperature and pressure inside the cabin are 25 °C and 0.8 bar, respectively. The compressor pressure ratio is 5, and suppose the air cools as it passes through the heat exchanger until it reaches room temperature. Calculate the required mass flow rate of the refrigerant and the coefficient of performance of the system only by considering the work of the compressor. The efficiency of Rom is 90% and the efficiency of isentropic turbine and compressor is 85%.

Used to cool the cockpit of a refrigerated aircraft (33 tons of simple air refrigeration). The aircraft speed is 1278 km / hr, the temperature and pressure outside are -10°C and 0.4 bar, respectively, and the temperature and pressure inside the cabin are 25 °C and 0.8 bar, respectively. The compressor pressure ratio is 5, and suppose the air cools as it passes through the heat exchanger until it reaches room temperature. Calculate the required mass flow rate of the refrigerant and the coefficient of performance of the system only by considering the work of the compressor. The efficiency of Rom is 90% and the efficiency of isentropic turbine and compressor is 85%.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

Q4: Why the stroke length of the racing cars' engines is always smaller than its bore diameter?
During an isentropic non-flow process with air, the pressure drops from 75psia to 30psia. The air has mass of 0.25 lbm and the initial temperature was 265°F. Find: a. The final temperature, in °F b. The heat transferred, in BTU C. The change in internal energy, in BTU d. The work done, in BTU
An auditorium is designed to seat 200 people. The ventilation rate is 2.50 x 104 m' h of outside air, or 3.3 x 10' kg/h. The outside temperature is -10°C dry- bulb, and the outside pressure is 101.3 kPa. Air leaves the auditorium at 23"C dry-bulb. The air temperature entering the auditorium is 21.6°C. Most nearly, how much heat should be supplied to the ventilation air? A. 120 kW B. 290 kW C. 540 kW D. 780 Kw
Q-1(c): Consider a case in which the air inside the pressurized cabin of a jet transport flying at some altitude of pressure, 0.9 atm and of temperature, 15°C. The total volume of air at any instant inside the cabin is 1800m3. If the air in the cabin is completely recirculated through the air conditioning system every 20 min, calculate the mass flow of air in kg/s through the system. I Answer:
A single-acting, single-cylinder air compressor is rated at 4.25 m3/min of air. The suction conditions are 1 atm and 27 C and discharge pressure is 1034 kPa. The compression process follows the equation PV1.35 = A. Determine the power, in kW, required to compress the air. B.)what is the engine kW power needed to drive the unit if the combined engine-compressor efficiency is 84%? C.)if the compressor is to run two-stage at optimum intercooler pressure with perfect intercooling, what will be percentage of power saved?
Steam is supplied to a two-stage turbine at 48 bar and 400 °C. It expands in the firstturbine until it is just dry saturated, then it is re-heated to 400 °C and expandedthroughthe second-stage turbine. The condenser pressure is 0.04 bar what is the pressure in bar at state 4 to 3 decimal places? what is the specific entropy in kJ/kg-K for state 5 to 4 d.p.?
1. An engine from a quarry vehicle used in the Build a Beach program of DEMR has a power requirement of 560 kW. Per hour of its operation, it ejects 234 MJ into its surroundings at 50 °C. If it behaves like a Carnot engine, answer the questions below. A. How much work (MJ) is done by the engine per hour of operation? B. What is the efficiency (%) of the engine?C. What is the temperature (°C) of the hot reservoir? 2. Determine the entropy change (kJ/K) associated to the conversion of 10 kg of ice at -11 °C to steam at 121 °C. 3. Anna and Beth are using another rare metal, the nth metal (c = 0.600 J/g-℃), to build the 5-kg cuirass of their design. Initially, the metal is at 2250 K. It is then submerged to 10 kg of water at 15 °C. If the remaining liquid water after submerging the metal is 8.5 kg, solve for the net entropy change (kJ/K) of the system.
Q3//a steam turbine develops 3000 kW when the steam is supplied at 10 bar, 250 °C. The vacuum reading on the condenser is 65 cm Hg when the barometer reads 75.2 cm Hg. The temperature rise of cooling water is limited to 15 °C. The temperature the condensate coming out of the condenser is 35 °C. Neglecting the air leakage to the system and assuming the expansion through the turbine as isentropic, find: 1. Specific steam consumption of the plant. 2. The thermal efficiency of the plant. 3. The quantity of cooling water circulated through the condenser per hour. Answer (5.05 kg/kWh, 25.5%, 503 ton/hr).
8. A single stage air compressor handles 0.454 cubic meter per sec of atmospheric pressure, 27 deg Cair and delivers it to a receiver at 652. 75 kPa. It is 0.85 and its mechanical efficiency is 0.90. If it rotates at 500 rpm, what power in kw is required to drive it?
In a refrigeration cycle, the refrigerant gains heat in the evaporator and in thesuction line. In a certain refrigeration system, R-134a gains 67.8 Britishthermal units per pound (Btu/lb) in the evaporator. It then gains 2.5 Btu/lb inthe suction line. Find in Btu/lb the total heat gained by the R-134a.
kg). Q3. The steam at 215 bar and 500 °C is supplied to a steam turbine. It expands to 40 bar and 280 °c. It is then reheated to 490 °C and expands to 8 bar and 270 °C. The steam coming out from the second expansion of the turbine is further reheated to 490 °C and expands to condenser pressure of 0.07 bar. The steam entering into the condenser is dry saturated. Assuming the pressure losses in first heater of 1 bar and in second heater 0.5 bar, find (a) the thermal efficiency and power developed if the flow of steam is 10 kg/s (b) the isentropic efficiency of the expansion stages. Neglect the pump work. Mis-n-n (42.8 %, 1738 kW,78.5%,95.4 %, 87%) Q4. The steam nt 100
The pressure of the air in a starting vessel is 40 bar and the temperature is 24°C. If a fire in the vicinity causes the temperature to rise to 65 °C. Neglect anyincrease in the volume of the vessel which is 5 liters. Please answer the following a. The thermodynamic process the problem representsb. the pressure, temperature, and volume after the processc. change in internal energy, change in enthalpy and change in entropyd. work nonflow and heat transferred