A four stage single acting air compressor running in an atmospheric at 87 KPa and 15 degrees Celsius has a free air delivery of 2,83 m³/min. The section pressure and temperature are 80 KPa and 32 degrees Celsius respectively, the delivery pressure is to be 7 MPa. The temperature at the start of compression in each stage is 32 degrees Celsius, take n=1.3 for all stages. Calculate : 1. The intermidiate pressure ratio in 3 decimal place 2.The intermidiate pressure at first, second and third stage in KPa 3. The mass flow rate in kg/min

Problems-1 1- compressor with compression ratio (7:1). The pressure, temperature and volume at the beginning of compression are (100kPa), (300K) and (0.07m') respectively. If the compression is adiabatic, determine the adiabatic and isothermal efficiency if the overall efficiency is (60%). Determine also the temperature at the end of compression. 2- Air compressor takes air of mass flow rate (9kg/min) at (100kPa) and (300K). Air leaves the compressor at (600kPa) to the tank. If the compression according to PV5-C. determine the required power to operate the compressor if the mechanical efficiency is (80%). 3- Air compressor compresses (7.8m/min) of air at (27°C) and (100kPa) to (925kPa). Determine the power required when the compression:(a) isothermal, (b) polytropic according to PV-C. find the averall efficiency if the mechanical efficiency is (90%). 4- Single acting single cylinder compressor with diameter (15cm) and stroke length of (22.5cm). The air enters the compressor at pressure…

Determine the mean effective pressure in kPa of a certain air -standard Diesel cycle which has a compression ratio of 16 and a cutoff ratio of 2. At the beginning of the compression process, the pressure and temperature of air is at 95,000 Pa and 300K, respectively. Roun-off your answer into two decimal places. hint: Linear Interpolation equation Y1 - Yo Yo (21 – æ) + Y1 (x – xo) | y = Yo + (x – co): *1 - 20 |

STEAM PROCESSES

Steam CERE KJ -Valve Control volume boundary Turbine Initially evacuated tank In case of emergencies, a turbine is connected to an active steam pipe line using a valve. When the valve is opened, steam from the pipe line, which is initially at 550°C and 10 MPa, flows through the turbine into a 0.64 m³ tank, which is initially evacuated. The valve is closed when the pressure inside the tank is 1.6 MPa and the temperature in the tank is 300°C. If the entire process is completed adiabatically, what is the amount of work generated from the turbine?

I need help on the following question: The vapour compression cycle (picture provided), utilises the refrigerant R134a flowing at 0.05 kg s-1. Assuming that the compression is adiabatic and reversible. If the actual input power to the compressor is 2 kW, then: 1. You need to determine the theoretical input power to the compressor and the heat transfer (Φ) to theevaporator. Take the enthalpies h1, h2, and h3 to be 238.41, 263.68 and 81.5 kJ kg-1 (use the 'NH3 Refrigeration Table' where you can find online). 2. You need to determine the coefficient of performance based on your answer to the previous question (1). 3. You need to determine the compressors mechanical efficiency.

The compression ratio of a compression-ignition engine is 13.5 to 1. The diameter of the cylinder is 505mm and the stroke to bore ratio is 1.21 to 1. At the beginning of the compression, the pressure and the temperature of the air in the cylinder is 105 Kpa and 51C, and compression follows the law PVn =C where n=1.33. Determine the following:1.1) The temperature at the end of compression 1.2) Volume at the beginning of compression 1.3) The mass of air inside the cylinder 1.4) Evaluate whether the work is done on or done by the air?