Engineering, 28.01.2020 02:31, jahnoibenjamin

Air flows through a device in which heat and work is exchanged. there is a single inlet and outlet, and the flow at each boundary is steady and uniform. the inlet flow has the following properties: flowrate 50 kg/s, t 25 °c, and velocity 150 m/s. heat is added to the device at the rate of 42 mw, and the shaft work is -100 kw (assume the efficiency is 100 %). the exit velocity is 400 m/s calculate the specific stagnation enthalpy (j/kg or kj/kg) at the inlet, and use the 1st law to calculate the specific stagnation enthalpy at the exit. assume constant cp1.0 kj/kg -k. calculate the temperature of the air at the exit. was the assumption of constant cp a good one?

Answers: 2

Show answers

Other questions on the subject: Engineering

Engineering, 04.07.2019 18:10, abdirahmansoloman

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Answers: 1

continue

Engineering, 04.07.2019 18:10, redrosesxx

Water at 55c flows across a flat plate whose surface temperature is held constant at 95c. if the temperature gradient at the plate's surface for a given value of x is 18 c/mm, find a) local heat transfer coefficient. b) heat flux

Answers: 3

continue

Engineering, 04.07.2019 18:10, nandalabella06

True or false (explain) (110)[111] is a slip system in bcc metals . the {111} family in fcc contains 8 planes. resolved shear stress (rss) in single crystals is just related to the applied stress. critical resolved shear stress (crss) in single crystal metals is direct proportional to the number of defects in the structure

Answers: 2

continue

Engineering, 04.07.2019 18:10, jesuslovesusall3

Courses that are developed by subject matter experts, internal or extemal to the college or university. these programs are marketed by the school (clo2) marks a)-vocational schools b)-vendor training c)-colleges & universities d)-continuing education programs

Answers: 2

continue

Do you know the correct answer?

Air flows through a device in which heat and work is exchanged. there is a single inlet and outlet,...