- How do you calculate capacity ratio?
- How do you calculate the effectiveness of a heat exchanger?
- What is a standard hour?
- What is capacity of heat exchanger?
- What do small and large NTU values tell about a heat transfer system?
- Why lmtd is used in heat exchanger?
- What is the formula for activity ratio?
- What is capacity ratio?
- What NTU means?
How do you calculate capacity ratio?
The capacity utilization ratio measures whether the total direct labour hours worked in a production cost centre in a period was greater or less than what was budgeted.
It is calculated as: (Actual direct labour hours worked ÷ budgeted direct labour hours) × 100%..
How do you calculate the effectiveness of a heat exchanger?
If one of the fluids is undergoing a change of phase throughout the entire heat exchanger and at a constant temperature (i.e. heat capacity is infinite), the thermal efficiency is simply Eff=1-exp(-U.A/Cmin), where Cmin is the heat capacity (m x cp) for the single phase fluid, U-overall heat transfer coeffcient and A …
What is a standard hour?
The standard hour is a useful concept in performance measurement and is relevant to items C2(e) and (f) in the Study Guide for MA1. Definition. A standard hour is the amount of work achievable, at the expected level of efficiency, in an hour.
What is capacity of heat exchanger?
For heat exchangers, heat transfer per unit temperature difference and heat capacity is defined by effectiveness of heat exchanger (ε) and capacity ratio of hot and cold streams (Cr). Effectiveness of heat exchanger decreases as capacity ratio increases.
What do small and large NTU values tell about a heat transfer system?
What do small and large NTU values tell about a heat transfer system? Answer: … Larger NTU value indicates that the limit has reached for heat transfer whereas smaller value of NTU indicates more opportunities for heat transfer.
Why lmtd is used in heat exchanger?
The log mean temperature difference (LMTD) is used to determine the temperature driving force for heat transfer in flow systems, most notably in heat exchangers. … The use of the LMTD arises, straightforwardly, from the analysis of a heat exchanger with constant flow rate and fluid thermal properties.
What is the formula for activity ratio?
The ratio shows how well the business manages its inventory levels and how frequently they are replenished. It is calculated by dividing the cost of goods sold by the average inventory for the same period.
What is capacity ratio?
The capacity ratio is actual hours worked / budgeted hours. … The capacity ratio is simply looking at whether we got more or less hours of labour than we budgeted to get.
What NTU means?
NTU means number of transfer units. It signifies that the heat transfer capacity of a given heat exchanger. NTU signifies how much number of units of heat, the given heat exchanger is capable of transferring from one fluid to other.