Air entering an air-cooled refrigeration system is indicated by （）.
A: frosting of the liquid line
B: higher than normal head pressure
C: a clear sight glass
D: abnormally cold reefer boxe
A: frosting of the liquid line
B: higher than normal head pressure
C: a clear sight glass
D: abnormally cold reefer boxe
举一反三
- In an operating diesel engine, which of the following conditions is an indication of a leaking air starting valve? A.Noise coming from that air starting valve B.Continuous operation of the starting air compressor C.Zero air pressure in the air starting system D.Overheated starting air pipe to the cylinder head
- Diesel engine air start system check valves are opened by （） A: an air start cam B: cylinder compression pressure C: starting air pressure D: valve spring
- The freight rate of air express is much higher than that of other air transportation mode.
- The pressure of pilot air is usually （） than that of starting air.
- As a tornado chaser just waking up in the morning, what meteorological conditions would you seek if you were interested in viewing a tornado that afternoon? (Select all that apply) A: Triggering cold front B: Warm moist air near the Earth's surface C: Warm moist air aloft D: Receding warm front E: Conditional instability in the atmosphere F: Surface high pressure system G: Cold dry air aloft H: Surface low pressure system