Most high pressure areas are accompanied by（）.

相似题目

• High firing pressures and a low exhaust temperature in a diesel engine may result from （）.

  A . decreased piston to cylinder head clearance B . increased exhaust system back pressure C . early fuel injection timing D . low scavenge air temperature

  查看最佳答案

• （）uses one or two high pressure pumps for all the cylinders with one more standby, while（）have a separate high-pressure pump for each cylinder.

  A . A common rail engine；conventional engines B . A conventional engine；common rail engines C . A marine diesel engine；most other engines D . A two-stroke engine；four-stroke engine

  查看最佳答案

• When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.

  A . increase the amount of cooling water to the condenser B . decrease the amount of cooling water to the condenser C . add more refrigerant to the system D . remove some refrigerant from the system

  查看最佳答案

• The weather is often（）in a high-pressure area.

  A . fine B . cloudy C . rainy D . windy

  查看最佳答案

• One cause of high head pressure occurring in a refrigeration system can be （）.

  A . insufficient cooling water flow to the condenser B . a low refrigerant charge in the system C . the liquid valve is open too much D . high evaporator superheat

  查看最佳答案

• The atmosphere in the vicinity of a high pressure area is called a(n)（）.

  A . anticyclone B . cold front C . occluded front D . cyclone

  查看最佳答案

• The device used for low-pressure control and high-pressure cutout on a compressor is called （）.

  A . cutout B . controller switch C . pressure controller D . cutout switch

  查看最佳答案

• Which of the following may cause that the compressor cuts off on high pressure cutout in a refrigeration plant? （） (1) faulty condensing (2) too few refrigerant (3) high discharge pressure

  A . any of (1) and (3) B . any of (1) and (2) C . any of (2) and (3) D . any of (1), (2) and (3)

  查看最佳答案

• Compared to a low pressure system，generally the air in a high is（）.

  A . warmer，less dense，and less stable B . cool，more dense，and drier C . muggy and cloudy D . extremely moist with high relative humidity

  查看最佳答案

• As a high pressure system approaches，the barometer reading（）.

  A . stays the same B . falls C . rises D . falls rapidly

  查看最佳答案

• If a refrigeration compressor is short cycling on high head pressure, you should （）.

  A . purge the condenser if the waterside is dirty B . check for proper water flow through the condenser C . increase the high pressure cutout setting D . reduce the cooling water flow

  查看最佳答案

• Two well-developed high pressure areas may be separated by a（）.

  A . Hill of low pressure B . Trough of low pressure C . Valley of low pressure D . Ridge of low pressure

  查看最佳答案

• A crew member reports that the high-pressure alarm light of a low-pressure CO2 fixed fire extinguishing system is illuminated. The most probable cause of this condition would be that（）.

  A . an air leak has developed in the tank B . the tank cooling system has malfunctioned C . the pilot cylinder discharge valve is leaking D . an excessive amount of insulation has been installed on the tank and piping

  查看最佳答案

• Fuel has to be injected into the engine at a high pressure so that it （） correctly.

  A . is purified B . in timed C . is compressed D . atomize

  查看最佳答案

• In the Northern Hemisphere，an area of counterclockwise wind circulation surrounded by higher pressure is a（）.

  A . low B . high C . warm front D . cold front

  查看最佳答案

• In a compression refrigeration plant the refrigerant is under low pressure in the （） and under high pressure in the （）.

  A . compressor；condenser B . condenser；evaporator C . throttle valve；evaporator D . evaporator；condenser

  查看最佳答案

• When normal operating pressure is applied to the hydraulic oil used in a high-pressure system, the oil （）.

  A . viscosity will decrease B . volume will increase C . volume will decrease D . pour point will be reduced

  查看最佳答案

• On the pole side of the trade wind belt，there is an area of high pressure with weak pressure gradients and light，variable winds. This area is called the（）.

  A . prevailing westerlies B . geostrophic winds C . doldrums D . horse latitude

  查看最佳答案

• One remedy for a high firing pressure, in addition to a high exhaust temperature in one cylinder of a diesel engine, is to （）

  A . increase scavenge air pressure B . reduce fuel booster pump pressure C . adjust the fuel rack D . retard fuel injector timing

  查看最佳答案

• Which of the listed problems could produce a high absolute pressure within a flash type evaporator?（）

  A . Production of high salinity distillate B . Seawater feed temperature below 165℃ C . A leak in the first stage demister D . A cracked distillate pump vent line

  查看最佳答案

• 207. The greater the pressure difference between a high and a low pressure center, the ______ .

  查看最佳答案

• You blood pressure is a little high. 译成：

  查看最佳答案

• A generally circular low pressure area is called a (n) ______.

  查看最佳答案

• The atmosphere in the vicinity of a high pressure areas is called a (n) _____.

  查看最佳答案