大工秋《水力學(xué)》在線作業(yè)（Great works,autumn, hydraulics, online homework, ）

1、大工11秋水力學(xué)在線作業(yè)2（Great works, 11 autumn, hydraulics, online homework, 2）In the fall of 11 "hydraulics" online homework 2First, determine the problem1. in pressure pipeline water hammer phenomenon in a cycle of four 6L/c long time for water hammer wave.A. errorB. rightAnswer: A1. depth of open

2、 channel flow flow pattern discrimination method, when the water depth is larger than the critical depth, jet flow.A. errorB. rightAnswer: AThe 1. N-N line, K- line is three K and the bottom slope perpendicular line.A. errorB. rightAnswer: A2. the equivalent modulus of flow through the canal bottom

3、slope i=0 flow.A. errorB. rightAnswer: A2. critical slope, N-N line and K- line overlap.A. errorB. rightAnswer: B2. prismatic channel constant non-uniform flow curve of qualitative analysis, the positive slope of the channel, when the channel is very long, in less than non uniform flow effect where

4、the tangent curve of water and N-N water line, reaching a uniform flow.A. errorB. rightAnswer: BMolecule 3. prismatic channel constant non-uniform flow differential equations, when I and J are not equal, the flow is non uniform flow.A. errorB. rightAnswer: BThe 3. step to eliminate water energy refe

5、rs to the kinetic energy before the jump section and the back section of the unit weight of water ratio.A. errorB. rightAnswer: AThe 3. series tube before pipe flow is equal to the flow and after the pipe and two pipe segments from the node.A. errorB. rightAnswer: B4. when the flow rate is equal to

6、the relative velocity, the interference wave upstream of the peak stagnation in the interference source, the influence of diffusion range from interference source to the downstream, the flow is called slow.A. errorB. rightAnswer: ATo solve the 4. flow modulus, when keeping other parameters unchanged

7、, volume modulus and Chezy coefficient is proportional to the square of.A. errorB. rightAnswer: AThe 4. channels are not allowed to rush flow rock generally about in the range of 15-80m/s.A. errorB. rightAnswer: AThe 5. rectangular channel when the best hydraulic section, the bottom width is two tim

8、es the depth of the water.A. errorB. rightAnswer: B5. flow under water flow is called pipe submerged discharge tube.A. errorB. rightAnswer: B5. flow by slow transition to jet water jump, but can not determine the position of hydraulic jump.A. errorB. rightAnswer: AIn 6. short calculation of local he

9、ad loss and has a different magnitude of head loss along the way, the general loss can be ignored.A. errorB. rightAnswer: A6. prismatic channel constant non-uniform flow curve of qualitative analysis, no a and B regions in the critical slope area, only C.A. errorB. rightAnswer: ALong tubes into a no

10、de flow and should be equal to the outflow from the node flow and 6. parallel.A. errorB. rightAnswer: BThe 7. is to make the economic flow rate of the minimum total cost of water supply system flow.A. errorB. rightAnswer: B7. from the construction perspective, I should be consistent with the slope o

11、f the terrain slope, so as to make the cut and fill equal, reduce project cost.A. errorB. rightAnswer: B7. depth of open channel flow flow pattern discrimination method, when the water depth is equal to the critical depth of flow, critical flow.A. errorB. rightAnswer: BIn the whole wave pipe passing

12、 back and forth time required for a phase 8. water hammer.A. errorB. rightAnswer: BIn the 8. section shape, size and roughness of the prismatic channel along the same, when flow rate is constant, the bottom slope is steep, the normal depth is greater.A. errorB. rightAnswer: A8. bottom slope method o

13、nly for uniform flow in open channel flow judging the degree of urgency.A. errorB. rightAnswer: BNineAny liquid through pipe parallel to the same head loss.A. errorB. rightAnswer: B9. water hammer has favorable side of it, using the water hammer pressure can be realized, has certain use value in the

14、 local conditions.A. errorB. rightAnswer: BThe 9. channels are not allowed to red clay is concerned about the general flow rate in the range of 10-15m/s.A. errorB. rightAnswer: A10. in the hydraulic jump length calculation, when the hydraulic jump length is 6.1 times the sequent depth calculation, i

15、s required before the jump section of the Froude number in the range of 4.5-10.A. errorB. rightAnswer: B10. water is water from flowing down through the critical depth of the transition to local water jet water falling sharply phenomenon.A. errorB. rightAnswer: B10. uniform open channel flow conditi

16、ons generated in along the rough coefficient according to the linear relationship between increasing.A. errorB. rightAnswer: ATwo, RadioButtonListThe 1. rectangular channel when the best hydraulic section, the bottom width is 10m, depth is ().A. 2mB. 5mC. 15mD. 25mAnswer: B1. a trapezoid section of

17、irrigation canal, water cut area of 39 square meters, wet week 18.49m, hydraulic radius ().A. 1.25B. 1.79C. 2.11D. 3.96Answer: C1. prismatic channel constant non-uniform flow curve of qualitative analysis, as gentle, is ().A. N-N on the line at K- KB. N-N is located in K- line under the lineThe C. N

18、-N line and K- line overlapThere is no D. N-N lineAnswer: AA 2. channel cross section is rectangular, the width is 2m, depth of 1m, while wet week ().A. 2B. 4C. 6D. 8Answer: BHydraulic radius R 2. a trapezoidal canal channel for 5m, then (depth).A. 8MB. 10mC. 15mD. 50mAnswer: BA 2. channel cross sec

19、tion is rectangular, the width is B, depth of H, while wet week ().A. b+2hB. b+hC. BHD. 2bhAnswer: A3. if the flow velocity of v=12m/s, the relative velocity is c=6m/s, the Froude number is ().A. 0.6B. 0.8C. 1D. 2Answer: DThe 3. section is a trapezoid open channel, the channel bottom width of 2.2M,

20、depth of 2m, the slope coefficient m=1.5, while wet week () M.A. 5.12B. 6.37C. 8.23D. 9.41Answer: DThe 3. channels are not allowed for the general flow of sand rushed about (range).A. 2.2-3.4B. 1.2-5.15C. 0.55-3.4D. 0.35-2.2Answer: D4. a simple long tube, flow Q=0.10m3/s, hydraulic gradient J=0.015,

21、 the ratio of resistance for the pipe (s2/m6).A. 1.500B. 1.970C. 2.835D. 4.500Answer: AA total of 4. pump head for 63.78m, the pump efficiency of 75%, through the pump flow rate is 60L/s, known as 9.8kN/m3, the density of water, water pump installed capacity (kW).A. 15B. 25C. 50D. 100Answer: C4. a w

22、ater pump installed capacity of 25kW, the pump efficiency of 75%, through the pump flow rate is 60L/s, the known water density was 9.8kN/m3, total head of the pump is equal to (m).A. 52.34B. 15.25C. 22.93D. 31.89Answer: D5. a trapezoid section of irrigation canal, water cut area of 55 square meters,

23、 wet week is 11m, then the hydraulic radius ().A. 1.5mB. 2.5mC. 5mD. 15mAnswer: CThe physical meaning of the Froude number 5. is mainly expressed on the role in water ().A. inertial force and gravity ratioThe inertia force and gravity and B.C. inertia force and viscous force ratioD. inertia force an

24、d viscous force andAnswer: A5. a simple long tube, length L=600m, Q=0.21m3/s flow, hydraulic gradient J=0.015,The pipe resistance (s2/m6) than for.A. 0.236B. 0.340C. 0.497D. 0.582Answer: BThree multiple-choice questions1. flow calculation formula of Chezy coefficient related to the following factors

25、. ()The cross-section of A.B. section sizeC. side wall roughnessD. slope heightAnswer: ABC1. the water jump function characteristics is correct to say that ().A. depth before the jump is, the smaller the sequent depthB. depth before the jump is bigger, the greater the sequent depthC. step function i

26、s the maximum value, the corresponding depth of critical depthD. water step function for minimum value, the corresponding depth of critical depthAnswer: AD1. Froude number is () a dimensionless number.A. flow velocityB. section areaC. velocity headThe relative velocity D.Answer: AD2. when the Froude

27、 number is less than 1, then ().The role of A. in the gravity flow plays the main roleThe role of B. in the current inertial force plays a main roleC. flow is slowD. jet flowAnswer: AC2. a simple long tube, length L=100m, Q=0.15m3/s flow, hydraulic gradient J=0.015, the following statement is correc

28、t ().A. pipe ratio values of 0.667s2/m6B. pipe ratio values of 2.832s2/m6C. pipe head loss is 1.5mD. pipe head loss is 5.6mAnswer: AC2. in the design of uniform flow channels, the best hydraulic section refers to the () is known, the design of cross section area of the smallest section.A. flowB. bot

29、tom slopeC. roughness coefficientD. areaAnswer: ABC3. the following statement is correct (C2).A. slopeThe steep slope B.C. backwater curveD. precipitation curveAnswer: BCThe calculation of 3. short hydraulic calculation, which is included in the pipeline (hydraulic).A. pipeline in the velocity headB

30、. local head lossC. head loss along the wayD. gravity lossAnswer: ABCThe following 3. conditions of producing uniform flow in open channel is correct to say that ().The constant A. along the path of constant flow flowB. the velocity constant of unsteady flowC. is the bottom slopeD. flat slopeAnswer:

31、 ACThe relationship between the parameters related to the following 4. long tube in the statement is correct ().A. velocity head is far greater than the local head lossB. velocity head is far greater than the head loss along the wayC. head loss along the way is far greater than the local head lossD. and local head loss of velocity head and much