ISRO Scientist or Engineer Refrigeration & Air-Conditioning 2018

The specific speed of a centrifugal pump delivering 810 Litres of water per sec. against head of 16 mts. at 725 RPM is

A centrifugal pump delivers 1000 lts per minute at 2000 RPM against total head of 50 mts. and requires 32 BHP for its operation. If speed is reduced to 1000 RPM, the discharge and head developed will be

A flow is said to be supersonic, if the

Fouling factor is used in heat exchangers due to

In a Counter flow heat exchanger design, fluid rates and specific heats were chosen in such a manner that heat capacities of both the fluids are same. A hot fluid enters at $$100^\circ$$ C and leaves at $$60^\circ$$C. The cold fluid enters heat exchanger at $$40^\circ C$$. The mean temperature difference between the two fluids is

The unit of overall coefficient of heat transfer is:

The heat transfer by conduction through a thick cylinder of inner radius $$r_{1}$$ ,outer radius $$r_{2}$$, Higher temperature $$T_{1}$$,lower temperature $$T_{2}$$, length of cylinder l and thermal conductivity k is given by:

According to Stefan-Boltzmann law, the total radiation from black body per second per unit area is directly proportional to the

In a condenser of a power plant, the steam condenses at temperature of $$60^\circ$$ C. The cooling water enters at $$30^\circ$$C and leaves at $$45^\circ$$C. The logarithmic mean temperature difference will be around

In shell and tube heat exchanger, baffles are mainly used for