Fundamentals of Chemical Engineering: One Question per Day – Fluids Knowledge
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1. For turbulence, ( ). (A) Only axial velocity, with no radial velocity. (B) Turbulent viscosity does not change with the flow pattern or the distance from the pipe wall. (C) A very thin layer of laminar flow remains near the pipe wall. (D) Re must be greater than 4,000. 2. Regarding pipe flow, which factor has no influence on the change in the flow pattern of the liquid? ( ) (A) Geometric dimensions of the liquid (B) Average velocity of the liquid (C) Density and viscosity of the liquid (D) Surface tension of the liquid and Plan’s number. 3. The strength parameters of metals are determined through ( ). (A) Calculation (B) Estimation (C) Comparison (D) Experiment. 4. Stable variable stress can be divided into three types of curved variable stress; which of the following does not belong to stable variable stress? ( ) (A) Asymmetric cyclic stress (B) Pulsating cyclic stress (C) Random stress (D) Symmetric cyclic stress Answer: C D D C
C D D C~~~~~~~~~~~~~~~
1、C 2、D 3、D 4、C
1、C 2、D 3、D 4、C
1、C ； 2、D ； 3、D ； 4、C ；
1. For turbulence, ( C ). (A) Only axial velocity, with no radial velocity. (B) Turbulent viscosity does not change with the flow pattern or distance from the pipe wall. (C) A very thin layer of laminar flow remains near the pipe wall. (D) Re must be greater than 4,000. 2. Regarding pipe flow, the factor that has no effect on the change in the flow pattern of the liquid is (D). (A) Geometric dimensions of the liquid (B) Average velocity of the liquid (C) Density and viscosity of the liquid (D) Surface tension of the liquid and Plan’s number. 3. The strength parameters of metals are determined through (D). (A) Calculate (B) Estimate (C) Compare (D) Test. 4. Stable variable stress can be divided into three types of curved variable stress; the one that does not belong to stable variable stress is (C). (A) Asymmetric cyclic stress (B) Pulsating cyclic stress (C) Random stress (D) Symmetric cyclic stress
Answer: C D D C
1. For turbulence, (c). (A) Only axial velocity, with no radial velocity. (B) Turbulent viscosity does not change with the flow pattern or distance from the pipe wall. (C) A very thin layer of laminar flow remains near the pipe wall. (D) Re must be greater than 4,000. 2. Regarding pipe flow, the factor that has no effect on the change in the flow pattern of the liquid is (D). (A) Geometric dimensions of the liquid (B) Average velocity of the liquid (C) Density and viscosity of the liquid (D) Surface tension of the liquid and Plan’s number. 3. The strength parameters of metals are determined through (D). (A) Calculate (B) Estimate (C) Compare (D) Test. 4. Stable variable stress can be divided into three types of curved variable stress; the one that does not belong to stable variable stress is (C). (A) Asymmetric cyclic stress (B) Pulsating cyclic stress (C) Random stress (D) Symmetric cyclic stress
1. For turbulence, ( C ). 2. In terms of flow, the factor that has no effect on the flow pattern transformation of liquids is (D). 3. The strength parameters of metals are obtained through (D). 4. Stable variable stress can be divided into three types of curved variable stress; the one that does not belong to stable variable stress is (C).
1. For turbulence, ( C ). (A) Only axial velocity, with no radial velocity. (B) Turbulent viscosity does not change with the flow pattern or the distance from the pipe wall. (C) A very thin layer of laminar flow remains near the pipe wall. (D) Re must be greater than 4,000. 2. Regarding pipe flow, the factor that has no effect on the change in the flow pattern of the liquid is (D). (A) Geometric dimensions of the liquid (B) Average velocity of the liquid (C) Density and viscosity of the liquid (D) Surface tension of the liquid and Plan’s number. 3. The strength parameters of metals are determined through (D). (A) Calculation (B) Estimation (C) Comparison (D) Experiment 4. Stable variable stress can be divided into three types of curved variable stress; the one that does not belong to stable variable stress is (C). (A) Asymmetric cyclic stress (B) Pulsating cyclic stress (C) Random stress (D) Symmetric cyclic stress
1、C 2、D 3、D 4、C. . .