1.The heat transfer coefficient with phase change is smaller than the heat transfer coefficient without phase change. 有相变的传热系数小于无相变的传热系数。（ ）
A:正确
B:错误
答案:错误
2.The settling velocity of spherical particles in static fluid can be calculated by Stokes formula.球形颗粒在静止流体中作自由沉降时，其沉降速度 可用斯托克斯公式计算。（ ）
A:对
B:错
答案:错
3.The non-condensable gas contained in the steam will increase the condensation heat transfer coefficient. 蒸汽中所含的不凝气会使冷凝传热系数上升。（ ）
A:错误
B:正确
答案:错误
4.One of the main differences between centrifugal sedimentation velocity and gravity sedimentation velocity is that the former is a constant value while the latter is not. 离心沉降速度与重力沉降速度的主要区别之一是前者是定值，而后者则不是定值。（ ）
A:对
B:错
答案:对
5.Fourier's law is the basic law to describe thermal convection. 傅立叶定律为描述热对流的基本定律。（ ）
A:对
B:错
答案:错
6.Viscosity of a fluid decreases with temperature. 流体的粘度随温度上升而下降。（ ）
A:错
B:对
答案:对
7.At the same temperature, the value of the absorption is equal to the blackness of an object. 在同一温度下，物体的吸收率和黑度在数值上是相同的。（ ）
A:对
B:错
答案:对
8.In the dust chamber, the necessary condition for particles to be separated is that the settling time of particles should be greater than or equal to the residence time of gas in the room. 在降尘室里，颗粒可被分离的必要条件是颗粒的沉降时间应大于或等于气体在室内的停留时间。（ ）
A:错误
B:正确
答案:错误
9.A very large Reynolds number implies that inertia dominates viscosity. 很大的雷诺数意味着惯性效应主宰了粘性效应。（ ）
A:正确
B:错误
答案:正确
10.Increasing fluid’s velocity and increasing fluid’s disturbance can increase the total heat transfer coefficient. 提高流体流速、增加流体的扰动可提高总传热系数。（ ）
A:对
B:错
答案:对
11.The centrifugal pump flow regulation methods are_____. 离心泵的流量调节方法_____. ( )
A:Change the pump speed改变泵的转速
B:Bypass regulation旁路调节
C:Change the pump outlet valve opening改变泵出口阀门开度
D:Reduce impeller diameter减小叶轮直径。
A:The convective heat transfer coefficient decreases with the increase of fluid viscosity 对流传热系数随着流体黏度的增加而减小 B:The convective heat transfer coefficient increases with the increase of the heat capacity of the fluid 对流传热系数随着流体热容的增加而增大 C:The convective heat transfer coefficient decreases with the increase of fluid density 对流传热系数随着流体密度的增加而减小 D:The convective heat transfer coefficient increases with the increase of the thermal conductivity of the fluid对流传热系数随着流体导热系数的增加而增大 13.In the design of shell and tube heat exchanger, it is reasonable to choose the flow diameter of the fluid . 在管壳式换热器的设计中，关于流体流径的选择，合理的是 。( ).
A:Unclean and scale-prone fluids are easy to enter the pipe 不洁净和易结垢的流体易走管内 B:Fluid with high pressure is easy to pass through the tube 压强高的流体易走管内 C:Corrosive fluids are easy to enter the pipe 腐蚀性的流体易走管内 D:Liquid with high viscosity or small flow rate is easy to go between tubes 黏度大的液体或流量较小的流体易走管间 14.In the following heat exchanger, the tubular heat exchanger are . 下列换热器中，属于管式换热器的是 。( )
A:Tubing heat exchanger 套管式换热器 B:Floating head heat exchanger 浮头式换热器 C:Jacket heat exchanger 夹套式换热器 D:Snake-tube heat exchanger 蛇管式换热器 15.The particle size of a certain particle settles in the dust-settling chamber. If the height of the chamber doubles, its productivity will be_______. 某粒径的颗粒在降尘室中沉降，若降尘室的高度增加一倍，则该降尘室的生产强度将_______。（ ）。
A:为原来的1/2 Halved B:不确定 Uncertain C:增加一倍 Doubled D:不变 Invariant 16.Fanning friction factor is ratio of _____. 范宁摩擦因数是_____之比。( )
A:shear stress at center to pressure head 管中心处切应力与静压头 B:shear stress at wall to pressure head 管壁处切应力与静压头 C:shear stress at center to velocity head管中心处切应力与动压头 D:shear stress at wall to velocity head管壁处切应力与动压头 E:shear stress at wall to elevation head管壁处切应力与位压头 17.Vacuum gauges can be used to measure the absolute pressure that is ( ) . 真空表可以用于测量什么范围的绝对压强？（ ）
A:equals to the external atmospheric pressure 等于外界大气压 B:far more than the external atmospheric pressure 远大于外界大气压 C: more than the external atmospheric pressure 大于外界大气压 D: less than the external atmospheric pressure 小于外界大气压 18.When discussing the separation performance of cyclone separators, the critical particle size refers to______. 讨论旋风分离器分离性能时，临界粒径这一术语是指_____。( )
A:The diameter of the smallest particle that can be completely separated by a cyclone separator旋风分离器能够全部分离出来的最小颗粒的直径 B:The minimum allowable diameter of cyclone separator旋风分离器允许的最小直径 C:It can maintain the maximum particle diameter in the stagnant flow pattern能保持滞流流型时的最大颗粒直径 D:The diameter of the cyclone separator at its highest efficiency旋风分离器效率最高时的旋风分离器的直径 19.A centrifugal pump is used to transfer the liquid between two open containers. If the liquid level height of the two containers is maintained unchanged, when the valve on the conveying pipeline is turning down, the total resistance of the pipeline will be _____. 用离心泵在两个敞口容器间输送液体。若维持两容器的液面高度不变，则当输送管道上的阀门关小后，管路总阻力将_____. ( )
A:invariant 不变 B:uncertain不确定 C:increased 增加 D:decreased 减小 20.In a pressure-driven flow in a pipe of diameter 2R, when r = _____, the second derivative of velocity with respect to radial direction d 2v / dr 2 = 0. 在直径为2R的圆管中的压力驱动流，速度的二阶微分在哪个位置处为0。( )
A:R B:R / 4 C:0 D:d 2v / dr 2 is never zero 该导数永不为0 E:R / 2 21.The disadvantage of ______ in the multi-effect evaporation process is that the viscosity of the feed liquid increases gradually along the flow direction, which reduces the heat transfer coefficient of the subsequent effect. _______加料的多效蒸发流程的缺点是料液粘度沿流动方向逐效增大，致使后效的传热系数降低。( )
A:Parallel feed 平流 B:Backward feed 逆流 C:Mixed feed 错流 D:Forward feed并流 22.For a centrifugal pump, if the fluid density is increased by 1.2 times, then at the same flow rate, the head increases by _____ times, the power increases by _____ times. _对某一离心泵，若输送的流体密度增大1.2倍，则在相同流量下，扬程增大倍数为 ____倍，功率增大倍数为__ __倍。( )
A:1.2, 1.2 B:1, 1.2 C:1, 2.4 D:1.2, 2.4 23.The working point of the centrifugal pump is _____. 离心泵的工作点是指_____. ( )
A:The point determined by the pump characteristic curve 由泵的特性曲线所决定的点 B:The intersection point of pump characteristic curve and pipeline characteristic curve 泵的特性曲线与管路特性曲线的交点 C:The point determined by line characteristics 由管路特性所决定的点 D:The point corresponding to the maximum pump efficiency 与泵最高效率时对应的点 24.In the evaporation unit, the more effective the temperature difference, the _______ the temperature difference loss. 蒸发装置中，效数越多，温度差损失_______。( )
A:Not changed 不变 B:Uncertain 不确定 C:Large 越大 r D:Less越少 25.In constant pressure filtration, the medium resistance can be not considered. If the filtration pressure difference is doubled, the filtrate quantity obtained at the same filtration time will be_______. 恒压过滤，如介质阻力不计，过滤压差增大一倍时，同一过滤时刻所得滤液量_______。( )
A:doubled 增大至原来的2倍 B:increased to 1.5 times增大至原来的1.5倍 C:increased to 20.5 times 增大至原来的20.5倍 D:quadrupled增大至原来的4倍 26.The pump efficiency η characterizes the fraction of energy being transferred to the liquid. For a centrifugal pump, dependence of η on the volumetric flow rate Q is _____. 泵效率反映了被分配给液体的能量占比，离心泵的效率η与流量Q的关系为_____. ( )
A:When Q increases, η decreases first and then increases Q增大，η先减小后增大 B:When Q goes up, η goes down Q增大则η减小 C:When Q goes up, η goes up Q增大则η增大 D:When Q increases, η increases first and then decreases Q增大，η先增大后减小 27.The boiling point is ______the solution in the evaporation chamber. 蒸发室内溶液的沸点______二次蒸汽的温度。（ ）
A:Higher than 高于 B:Equal to等于 C:Uncertain 不确定 D:Lower than 低于 28.When centrifugal pump stop operation, it should be _____. 离心泵停止操作时，应_____. ( )
A:Single pump first power off, multi-stage pump first close the outlet valve 单机泵先停电，多级泵先关出口阀 B:First close the outlet valve or power failure is same 先关出口阀或先停电均可 C:First power off and then close the outlet valve 先停电后关出口阀 D:First close the outlet valve and then power off 先关出口阀后停电 29.In the constant pressure filtration, the filter cake is incompressible and the medium resistance can be ignored. If the operating pressure difference increases by 1 times, the filtration rate increased to______. 恒压过滤时， 如滤饼不可压缩，介质阻力可忽略，当操作压差增加1倍，则过滤速率为原来的_______。（ ）
A:2 B:1 C:20.5 D:1/2 30.A tube heat exchanger, between the tubes with saturated water vapor to heat the air in the tube (air in the tube for turbulent flow), so that the air temperature from 20℃ to 80℃, now the air flow need to increase to 2 times of the original. If the air inlet and outlet temperature is kept constant, the heat transfer temperature difference should be times of the original. 某一套管换热器，管间用饱和水蒸气加热管内空气（空气在管内作湍流流动），使空气温度由 20℃升至 80℃，现需空气流量增加为原来的 2 倍，若要保持空气进出口温度不变，则此时的传热温差应为原来的 倍。( )
A:Uncertain 不能确定 B:1.149 C:1.74 D:2 31.The spherical particles settle freely in the stationary fluid, and when 10-4＜ Ret＜1, the settling velocity can be calculated by________. 球形颗粒在静止流体中自由沉降，当在10-4＜Ret＜1时，沉降速度可用_______计算。（ ）
A:Stokes Equation斯托克斯公式 B:Newton Equation牛顿公式 C:Maxwell Equation麦克斯韦公式 D:Allen Equation艾仑公式 32.The reading of vacuum gauge in the equipment is 100 mmHg, try to calculate the gauge pressure. Given that the atmospheric pressure in this area is 740mmHg, then what is the gauge pressure? 某设备真空表的读数是100 mmHg，请计算一下表压，假设当地大气压为740 mmHg，表压为多少？ ( )
A:640 mmHg B:-100 mmHg C:840 mmHg D:-740 mmHg 33.A liquid flows from a conduit into another whose diameter is twice as big. The mean speed is 7 m/s prior to the expansion. After passing the expansion, the mean speed for the liquid is ( ), and the local head loss due to the expansion is ( ). 某流体自一个圆管进入另一圆管，后者直径为前者2倍。流体在前一管道中的平均流速为7 m/s。则在后一管道的平均流速为（ ），此处的局部压头损失为（ ）。( )
A:1.75 m/s; 0.09 m B:1.75 m/s; 1.88 m C:1.75 m/s; 0.12 m D:1.75 m/s; 1.41 m E:1.75 m/s; 1.25 m 34.It is known that when the temperature is T, the radiation capacity of firebrick is greater than that of aluminum plate, and then the blackness of aluminum is the blackness of firebrick. 已知当温度为 T 时，耐火砖的辐射能力大于铝板的辐射能力，则铝的黑度 耐火砖的黑度。 ( )
A:Equal to 等于 B:less than 小于 C:Uncertain 不能确定 D:Greater than 大于 35.The purpose of using multi-effect evaporation is to improve_________. 采用多效蒸发的目的是为了提高_________。（ ）
A:Aforementioned three options ABC全选 B:The economy of heating steam加热蒸汽经济程度 C:Capacity 生产能力 D:The concentration of the finished solution完成液的浓度 36.When the density of the liquid changes, the pressure head H and shaft power N of the centrifugal pump change as _____. 当液体的密度改变时，离心泵的压头H和轴功率N的变化为_____. ( )
A:N均改变 B:H doesn't change, N changes H不变，N改变 C:H and N don’t change D:H and N change E:N均不变 F:H changes, N doesn't change H改变，N不变 37.With the decrease of the settling chamber height, the settling time becomes ______. 随着沉降室高度降低，则沉降时间______。( )
A:Shorter 更短 B:Invariant 不变 C: Longer 更长 D:Uncertain 不确定 38.A pipe of diameter 0.4 m and of length 1500 m is connected to outlet of a reservoir. The piezometric head at inlet A is 0.3 m. To increase discharge, another line of the same diameter is introduced parallel to the first in the second half of the length. The Darcy factor is 0.04 for all pipes and no minor loss is significant. The increase in discharge flow rate Q is _____. 如图，用一根直径为0.4 m，长度为1500 m的圆管AC从一储水罐中导出水流。管道入口A处的测压头为0.3 m。现为增大流率，特在管道中点B处增加一分支管路BD，该分管与原管相同，达西摩擦因数均为0.04。忽略所有局部阻力。如此则总流率Q增加了_____。
( )A:0.16 m3/s B:0.06 m3/s C:0.12 m3/s D:0.10m3/s E:0.02 m3/s 39.A cylindrical piston is moving back and forth within a cylindrical gas chamber as shown below. The piston’s speed is 0.8 m/s. The inner diameter of the chamber D = 100 mm, while of the piston the outer diameter d = 99.96 mm, the length l = 120 mm. A lubricant whose viscosity is 100 mPa s fills the space between the piston and the chamber wall. The lubricant flow is laminar. The viscous drag force on the surface of the piston is _____.如图，一圆柱形活塞在空心圆柱形的气缸中以0.8 m/s的速度往复运动。气缸内径D = 100 mm，活塞外径d = 99.96 mm，长度l = 120 mm。二者之间的缝隙中充满了粘度为100 mPa s的润滑油。油的流动方式为层流。作用于活塞侧面的粘性力大小为_____。
（ ）A:31 N B:62 N C:99 N D:122 N E:151 N
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