Which condition dramatically reduces a centrifugal pump's performance during oil-pipeline transfer?

💡 Explanation

Increasing the oil viscosity significantly increases frictional losses in the pump because viscous drag becomes dominant; therefore, pump efficiency reduces rather than improves if the fluid flows easier at lower kinematic viscosity due to lubrication.

• Which outcome occurs when the expansion valve fails closed in a refrigeration system with a positive displacement pump?
• Which risk increases when a single-phase load is unintentionally connected between two phases of delta-configured three-phase power?
• Which risk increases in concrete columns when chlorides penetrate to the level of the reinforcing steel?
• Which structural outcome occurs on a pre-stressed concrete bridge span undergoing prolonged high-temperature exposure?
• Which outcome occurs when stress corrosion cracking develops within prestressing tendons of a concrete bridge?
• In absorption chillers, which consequence results from a crystallization?