A shell-and-tube heat exchanger is to heat 10,000 kg/h of water from 16 to 84degreeC by hot engine oil flowing through the shell. The oil makes a single shell pass, entering at 160degreeC and leaving at 94'C, with an average heat transfer coefficient of 400 W/m2/K. The water flows through 11 brass tubes of 22.9 mm inside diameter and 25.4 mm outside diameter, with each tube making four passes through the shell. Assuming fully developed flow determine the required tube length per pass. For the tube length found in part (1), plot the effectiveness, fluid outlet temperatures, and water-side convection coefficient as a function of water flow rate for 5000 15,000 kg/h, with all other conditions remaining the same.
Answers
Assuming fully developed flow for the water, the required tube length per pass. is, L = 9.608 m.
What is heat exchanger?A system for transferring heat from a source to a working fluid is called a heat exchanger. Processes for cooling and heating both use heat exchangers. It is possible for the fluids to be in direct contact or separated from one another by a solid wall to prevent mixing.
They are extensively utilised in power plants, petrochemical plants, sewage treatment facilities, sewage treatment facilities, space heating, refrigeration, air conditioning, chemical plants, chemical petrochemical plants, and chemical plants.
An internal combustion engine serves as the archetypal example of a heat exchanger because air is forced past radiator coils while an engine coolant circulates through them, cooling the coolant and heating the incoming air.
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Related Questions
Complete the following sentence.
Geometry is a field of ____ that studies the size, shape, and position of structures by analyzing space.
Answers
Answer:
Mathematics
Explanation:
⁄(⁄ ⁄•⁄ω⁄•⁄ ⁄)⁄
Answer:
It is a field if mathematics
Positive correlations of handle steeper incline of bicycle is what? a. Light weight frame b. Suspension. C. More gears. D. Soft comfort seat. E. Lights. Give me answer from objectives
Answers
Positive correlations of handle steeper incline of bicycle is a. Light weight frame.
What is the Positive correlations?A positive relationship implies that as one variable increments, the other variable moreover increments. Within the setting of cycling, handle steepness can influence the rider's pose and consolation level, which in turn can impact components such as speed, continuance , and generally performance.
Hence, Components which will influence the relationship between handle steepness and cycling execution might incorporate the rider's wellness level, the landscape being ridden on, the sort and quality of the bike components, and other person inclinations or variables.
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Reflection 3: What are some of the pros and cons to each of the three methods you have used?
Answers
There are different methods to calculate the balance in excel, but here are the pros and cons for three of the most common methods:
SUM formula:
Pros: Simple to use and easy to understand. Can be applied to a range of cells in a single formula.
Cons: Not flexible, as the formula must be modified if the size of the range changes.
Pivot Tables:
Pros: Can be used to summarize data from multiple sources and provides an interactive interface to manipulate the data.
Cons: Can be complex to set up and requires a good understanding of pivot tables.
VLOOKUP:
Pros: Can be used to find specific values in a large data set and return the corresponding value from a different column.
Cons: Can be slow for large data sets and can be prone to errors if not used correctly. Can also be complicated for users who are not familiar with the function.
What is VLOOKUP?A lookup table is an array in computer science that substitutes runtime computation with a simpler array indexing operation.
The VLOOKUP function is defined as follows: =VLOOKUP(What you want to look up, where you want to look for it, the column number in the range holding the value to return, return an Approximate or Exact match - denoted as 1/TRUE, or 0/FALSE).
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Give upper (O(⋅)) asymptotic bounds for the following recurrences. You may assume a O(1) base case for small n. Justify your answer by some combination of the following: deriving how much total work is done at an arbitrary level k, how many levels there are, and how much work is required to merge (function body). For each recurrence, state whether or not it is top-heavy, bottom-heavy, or even work. Answers that only cite the Master theorem will not receive full credit. 1. T(n)=2T(
2
n
)+O(n) 2. T(n)=2T(
2
n
)+O(1) 3. T(n)=7T(
2
n
)+O(n
3
) 4. T(n)=7T(
2
n
)+O(n
2
) 5. T(n)=4T(
2
n
)+O(n
2
n
) 6. T(n)=4T(
2
n
)+O(nlog
2
(n))
Answers
The upper asymptotic bound for the recurrence T(n) = 2T(2n) + O(n) is O(n log n).
Justification: At each level, the work done is O(n). There are log n levels because the input size is divided by 2 at each level. Additionally, the work required to merge is O(n) since the merging step is O(n). Therefore, the total work can be expressed as O(n log n), indicating a top-heavy recurrence.
The upper asymptotic bound for the recurrence T(n) = 2T(2n) + O(1) is O(log n).
Justification: At each level, the work done is constant, O(1). There are log n levels because the input size is divided by 2 at each level. Since there is no additional merging or other work, the total work remains constant at each level. Therefore, the total work can be expressed as O(log n), indicating an even work recurrence.
The upper asymptotic bound for the recurrence T(n) = 7T(2n) + O(n^3) is O(n^3 log n).
Justification: At each level, the work done is O(n^3). There are log n levels because the input size is divided by 2 at each level. The merging step requires O(n^3) work. Therefore, the total work can be expressed as O(n^3 log n), indicating a top-heavy recurrence.
The upper asymptotic bound for the recurrence T(n) = 7T(2n) + O(n^2) is O(n^2 log n).
Justification: At each level, the work done is O(n^2). There are log n levels because the input size is divided by 2 at each level. The merging step requires O(n^2) work. Therefore, the total work can be expressed as O(n^2 log n), indicating a top-heavy recurrence.
The upper asymptotic bound for the recurrence T(n) = 4T(2n) + O(n^(2n)) is O(n^(2n)).
Justification: At each level, the work done is exponential, O(n^(2n)). There are log n levels because the input size is divided by 2 at each level. The merging step does not contribute significantly to the overall complexity. Therefore, the total work can be expressed as O(n^(2n)), indicating a top-heavy recurrence.
The upper asymptotic bound for the recurrence T(n) = 4T(2n) + O(n log₂(n)) is O(n log₂(n)).
Justification: At each level, the work done is O(n log₂(n)). There are log n levels because the input size is divided by 2 at each level. The merging step requires O(n log₂(n)) work. Therefore, the total work can be expressed as O(n log₂(n)), indicating an even work recurrence.
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PLEASE HELP I NEED THIS ASP!!
Answers
Answer:
up up down down
Explanation:
left right left right b a select start
One method that is used to grow nanowires (nanotubes with solid cores) is to initially deposit a small droplet of a liquid catalyst onto a flat surface. The surface and catalyst are heated and simultaneously exposed to a higher-temperature, low-pressure gas that contains a mixture of chemical species from which the nanowire is to be formed. The catalytic liquid slowly absorbs the species from the gas through its top surface and converts these to a solid material that is deposited onto the underlying liquid-solid interface, resulting in construction of the nanowire. The liquid catalyst remains suspended at the tip of the nanowire. Consider the growth of a 15-nm-diameter silicon carbide nanowire onto a silicon carbide sururface. The surface is maintained at a temperature of Ts = 2400 K and the particular liquid catalyst that is used must be maintained in the range 2400 K ≤ Tc ≤ 3000 K to perform its function. Determine the maximum length of a nanowire that may be grown for conditions characterized by h = 105 W/m2.K and T[infinity] = 8000 KT. Assume properties of the nanowire are the same as for bulk silicon carbide.
Answers
Answer: maximum length of the nanowire is 510 nm
Explanation:
From the table of 'Thermo physical properties of selected nonmetallic solids at At T = 1500 K
Thermal conductivity of silicon carbide k = 30 W/m.K
Diameter of silicon carbide nanowire, D = 15 x 10⁻⁹ m
lets consider the equation for the value of m
m = ( (hP/kAc)^1/2 ) = ( (4h/kD)^1/2 )
m = ( ((4 × 10⁵)/(30×15×10⁻⁹ ))^1/2 ) = 942809.04
now lets find the value of h/mk
h/mk = 10⁵ / ( 942809.04 × 30) = 0.00353
lets consider the value θ/θb by using the equation
θ/θb = (T - T∞) / (T - T∞)
θ/θb = (3000 - 8000) / (2400 - 8000)
= 0.893
the temperature distribution at steady-state is expressed as;
θ/θb = [ cosh m(L - x) + ( h/mk) sinh m (L - x)] / [cosh mL+ (h/mk) sinh mL]
θ/θb = [ cosh m(L - L) + ( h/mk) sinh m (L - L)] / [cosh mL+ (h/mk) sinh mL]
θ/θb = [ 1 ] / [cosh mL+ (h/mk) sinh mL]
so we substitute
0.893 = [ 1 ] / [cosh (942809.04 × L) + (0.00353) sinh (942809.04 × L)]
L = 510 × 10⁻⁹m
L = 510 nm
therefore maximum length of the nanowire is 510 nm
design a filter that has infinite dc gain, a gain of one from 1hz to 100 hz and filters (1st order) any signals above 100 hz. a) sketch the bode plot b) sketch the s-plane c) write the transfer function of the filter d) write the differential equation e) write out the unforced transient response f) write out the frequency response
Answers
To design a filter with infinite DC gain and a gain of one from 1Hz to 100Hz, while filtering any signals above 100Hz (1st order), we can use a high-pass filter with a cutoff frequency of 100Hz.
a) The Bode plot of this filter would show a flat line at infinity for frequencies less than 1Hz, a slope of 20dB/decade from 1Hz to 100Hz, and a sharp drop of 20dB/decade for frequencies above 100Hz.
b) The s-plane would show a single pole at -100rad/s.
c) The transfer function of this filter can be written as: H(s) = (s+100)/s
d) The differential equation for this filter can be written as: \(y''(t) + 100y'(t) + y(t) = 100x'(t) + x(t)\)
e) The unforced transient response for this filter can be written as: y(t) = \([c1e^(-50t)cos(99.5t) + c2e^(-50t)sin(99.5t)]\)
f) The frequency response for this filter is given by: H(jw) = (jw + 100) / jw.
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What is the output? for num in range(3): print (num + 5)
Answers
Answer: 5 6 7
Explanation:
you can run this in python and get this result
The output for the given program is: 5 6 7
What is Python Programming Language?This refers to the high-level language that was created and is used for data structures due to its OOP (object-oriented programming).
Hence, this python code asks for an array of numbers in the range of 3 and when that is found, it should make a display of the number and increment it.
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For each of the seven devices in the circuit below, determine whether the device is a supplier or recipient of power, and how much power it is supplying or receiving?
Answers
Whether a slowly increasing market is preventing enterprises in the area from making a profit.
The specs give an explanation of the desired system's behaviors, attributes, or traits. Therefore, the main duty of the criteria is to ensure that all concerned parties understand them. The procedures involved in working with requirements include identification, analysis, verification, and management, among others. How do you format examples of requirements? The requirements must be clear, specific, condensed, and exhaustive. Make sure the requirements are concise, clear, and to the point while yet being able to capture the entire demand. Short sentences facilitate reading comprehension and make it simple to organize the demands. The specs give an explanation of the desired system's behaviors, attributes, or traits. Therefore, the main duty of the criteria is to ensure that all concerned parties understand them.
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When in regular operation, ash and other debris should be removed _______ from the combustion chamber of a wood-burning heater.
Answers
When in regular operation, ash and other debris should be removed daily from the combustion chamber of a wood-burning heater.
What is meant by a combustion chamber?A wood stove radiates heat as it warms up via the stove's top and walls. The nearby region is warmed by the radiant heat, which can also warm other areas of the house thanks to the natural airflow in the building.
Fans using electric or convection power can help move this heat around to warm a bigger space. Some wood stoves use a convection chamber that wraps around the firebox to combine radiant and convection heat into a single appliance. Cool air is drawn into this convection chamber where it is heated and then circulated once again around the space.
Ash and other debris should be taken out of a wood-burning heater's combustion chamber every day when it is in regular use.
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A drug user who reports "hearing" colors and "seeing" sounds has most likely used _______
A. LSD
B. speed
C. stimulants.
Answers
Hope this helps x
A rectangular channel 3-m-wide carries 12 m^3/s at a depth of 90cm. Is the flow subcritical or supercritical? For the same flowrate, what depth will five critical flow?
Answers
Answer:
Super critical
1.2 m
Explanation:
Q = Flow rate = \(12\ \text{m}^3/\text{s}\)
w = Width = 3 m
d = Depth = 90 cm = 0.9 m
A = Area = wd
v = Velocity
g = Acceleration due to gravity = \(9.81\ \text{m/s}^2\)
\(Q=Av\\\Rightarrow v=\dfrac{Q}{wd}\\\Rightarrow v=\dfrac{12}{3\times 0.9}\\\Rightarrow v=4.44\ \text{m/s}\)
Froude number is given by
\(Fr=\dfrac{v}{\sqrt{gd}}\\\Rightarrow Fr=\dfrac{4.44}{\sqrt{9.81\times 0.9}}\\\Rightarrow F_r=1.5\)
Since \(F_r>1\) the flow is super critical.
Flow is critical when \(Fr=1\)
Depth is given by
\(d=(\dfrac{Q^2}{gw^2})^{\dfrac{1}{3}}\\\Rightarrow d=(\dfrac{12^2}{9.81\times 3^2})^{\dfrac{1}{3}}\\\Rightarrow d=1.2\ \text{m}\)
The depth of the channel will be 1.2 m for critical flow.
A system that calls for subassemblies and components to be manufactured in very small lots and delivered to the next stage of the production process just as they are needed?
Answers
A system that calls for subassemblies and components to be manufactured in very small lots and delivered to the next stage of the production process just as they are needed is known as a Just-in-Time (JIT) system.
JIT is a manufacturing philosophy that aims to eliminate waste by producing only what is needed, when it is needed, and in the exact quantity required. This system requires careful coordination between suppliers, manufacturers, and customers to ensure that materials and parts are delivered on time and in the right quantities.
JIT has many benefits, including lower inventory costs, improved efficiency, reduced lead times, and higher quality products. However, it also requires a high degree of planning, communication, and flexibility to be successful. Overall, JIT is a complex but powerful system that can help organizations streamline their production processes and improve their bottom line.
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Mention any four thermodynamic properties.
Answers
Answer:
They are pressure, temperature, volume, entropy, internal energy, enthalpy, Gibbs function and Helmholtz functions
the voltage valve at which a zirconia O2S switches from rich to lean and lean to rich is
A) 0.5v (500mv)
B) 0.45v (450mv)
C) 0.25v (250mv)
D) 0.90v (900)
Answers
a step-up transformer is designed so that the output of its secondary winding is 2000 v (rms) when the primary winding is connected to a 110-v (rms) line voltage. (a) if there are 100 turns in the primary winding, how many turns are there in the secondary winding?
Answers
The relationship between the number of turns in the primary and secondary windings of a transformer is given by:Np/Ns= Vp/Vs = Ip/Iswhere Np and Ns are the number of turns in the primary and secondary windings respectively. Vp and Vs are the voltages across the primary and secondary windings.
Ip and Is are the currents through the primary and secondary windings respectively.Given that the output of the secondary winding is 2000 V (rms) when the primary winding is connected to a 110 V (rms) line voltage. Thus,Vp = 110 V (rms) and Vs = 2000 V (rms)Given that there are 100 turns in the primary winding, we need to find the number of turns in the secondary winding.
Thus, we can use the formula above to find the number of turns in the secondary winding.Np/Ns= Vp/VsNp/Ns= 110/2000Ns/Np= 2000/110Ns/Np= 18.18Approximately 18 turns (to two significant figures) are present in the secondary winding.
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to do you blur text in google docs
Answers
Answer:
I dont think you can blur text in google docs
What time will current of 10A transferred from a charges of 50C
Answers
Answer:
8×10^-19 seconds
Explanation:
i=∆q/∆t
=> ∆t=∆q/i=50×1.6×10^-19/10=8×10^-19(s)
the ancient romans perfected this type of arch and often used it in their architecture. T/F
Answers
It is true that the ancient Romans perfected this style of arch and frequently employed it in their construction.
Which architectural design was inspired by Roman architecture?
The architecture of Rome served as the inspiration for this type of stately mansion. Gothic style included this style of arch to aid in guiding devotees' sight skyward.
How did the Romans make use of the archway configuration?
Roman builders of both residential as well as commercial alike frequently employed the arch design. Around 700 BC, the Etruscans are thought to have given the idea of arches to the ancient Romans. Certain aspects of Greek architecture were also incorporated by the ancient Cultures into their own built environment.
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A 750-m section of river runs parallel to a channel 1,000 m away. An aquifer connecting the two has hydraulic conductivity equal to 7.0 m/day and an average thickness of 10 m. The surface of the river is 5.0 m higher than the surface of the channel. Estimate the rate of seepage (Qseepage) from the river to the channel.
Answers
The seepage rate (Qseepage) from the river to the channel can be calculated using Darcy's law as follows:Qseepage=K×A×(h1−h2)Where, K is the hydraulic conductivity of the aquifer, A is the cross-sectional area of the flow, h1 is the height of the water table in the river, and h2 is the height of the water table in the channel.
The height difference (h1-h2) drives the flow of water through the aquifer.
To determine the cross-sectional area of flow, we first need to calculate the width of the aquifer. The distance between the river and the channel is 1000 m, and the length of the river section is 750 m. Therefore, the width of the aquifer is 1000 - 750 = 250 m. The cross-sectional area of flow is equal to the width of the aquifer multiplied by its average thickness. Thus, A = 250 × 10 = 2500 m².
Substituting the given values into the equation, we have:
Qseepage = 7.0 × 2500 × (5.0)
Qseepage = 87,500 m³/day
Therefore, the estimated seepage rate from the river to the channel is 87,500 m³/day.
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Which of the following wouldn't be pictured on a fan motor's ladder logic diagram? A. Auxiliary contacts B. two Push-button control C. Boiler D. Mixing chamber
Answers
Answer:
c
Explanation:
:)
When a pungent odor is detected during a sealed system recovery and/or repair which of the following is most likely
Answers
Answer: A leak in the system
Explanation:
Construct a link mechanism of crank oa 30mm rotating clockwise rod ab 100mm and bc 50mm
Answers
Answer:
the answer is 180mm
Explanation:
the answer is 180mm.
The long slot on a 15-ampere, 125-volt, receptacle is the
conductor *
4 points
grounded
O phase "hot"
O equipment-grounding
O traveler
Answers
The long slot that is present in a 15-ampere, 125-volt, receptacle is known as the grounded conductor.
What is purpose of the long slot in the receptacle?The long slot is the grounded conductor that is placed in the receptacle to meet with relevant National Electrical Codes (NEC).
The grounded conductor is meant to connect to the ground either directly or indirectly for safety purposes.
In conclusion, option A is correct.
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Your company has been retained to start steel erection for a project. The steel will be delivered on an 18-wheel flat-bed truck and then lifted into place. You will have a crane on site, a Grove GMK 5175 all-terrain crane and you will be lifting with ½ steel chains. The crane is a 175 Ton telescoping crane and the crane will be sitting on Type B soil. The steel delivery consists of 48 pieces of W18x65 structural steel, Grade A 36, broken down as follows and delivered in 12 bundles of 4 pieces each.
13 pieces - 25’ long
17 pieces -50’ long
18 pieces – 15’ long
Based on the above, answer the following questions:
a. Neglecting the weight of the truck, what is the total weight of the steel load?
b. Assuming that the steel will be bundled and lifted as follows, calculate the weight of each of the lifts
4 pieces of 15 feet long, W18x65 Weight_______________________
4 pieces of 50 feet long, W18x65 Weight_______________________
4 pieces of 25 feet long, W18x65 Weight_______________________
c. With the soil conditions noted above,
Will the crane be able to safely lift the heaviest lift?
i. Yes
ii. No
d. What will be the maximum amount or load that can be lifted by this crane using the boom length of 155 feet?
Answers
Find the first-order kinematic coefficient of the gear train. What are the speed and direction of rotation of gear 8? ω,-1200 rev/min 4 15T 44T 33T 36T 487
Answers
The first-order kinematic coefficient of the gear train is 0.028. Gear 8 rotates in the clockwise direction with a speed of 42.86 rev/min.
What is the rotational direction and speed of gear 8 and what is the first-order kinematic coefficient of the gear train?The first-order kinematic coefficient of the gear train is a measure of the efficiency of power transmission through a gear train. It is defined as the ratio of the output speed of the final gear to the input speed of the first gear. In this case, the first-order kinematic coefficient is 0.028, which means that the output speed of gear 8 is only 2.8% of the input speed of gear 4.
To determine the rotational direction and speed of gear 8, we first need to identify the gear ratios for each pair of gears in the train. Starting from gear 4, we have a gear ratio of 44/15, which means that gear 5 rotates at a slower speed than gear 4 but with higher torque. Similarly, the gear ratio between gears 5 and 6 is 33/36, which means that gear 6 rotates at a faster speed than gear 5 but with lower torque.
Finally, we can calculate the speed and direction of rotation of gear 8 by multiplying the gear ratios of all the gears between gear 4 and gear 8. We have:
44/15 * 33/36 * 487/36 = 42.86
This means that gear 8 rotates at a speed of 42.86 rev/min in the clockwise direction.
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Which one of the follow techniques can be used when welding steels with poor weldability? a Use low heat input to increase the weld cooling rates b Use high hydrogen flux ingredients c Preheat the base material to reduce the weld cooling rates d Keep the grease and oil at the welding zone
Answers
The technique that can be used when welding steels with poor weldability is preheat the base material to reduce the weld cooling rates (option c)
Weldability refers to the ability of a material to be welded under certain conditions without producing defects, such as cracks or porosity, in the weld zone. Steels with poor weldability can be difficult to weld without producing defects, and often require special techniques to ensure a successful weld.
Preheating the base material is a common technique used when welding steels with poor weldability. By heating the base material before welding, the cooling rate of the weld zone can be reduced, which can help prevent the formation of cracks and other defects.
Preheating also helps to ensure that the material being welded is at a consistent temperature throughout the welding process, which can improve the quality of the weld.
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Hey guys can anyone list chemical engineering advancement that has been discovered within the past 20 years
Answers
Nanopesticides. The world population keeps growing. ...
Enantio selective organocatalysis. ...
Solid-state batteries. ...
Flow Chemistry. ...
Porous material for Water Harvesting. ...
Directed evolution of selective enzymes. ...
From plastics to monomers. ...
Determine the power output of the draw-works motor M necessary to lift the 600-lb drill pipe upward with a constant speed of 4 ft/s. The cable is tied to the top of the oil rig, wraps around the lower pulley, then around the top pulley, and then to the motor.
Answers
Answer:
\( \therefore \) The power output of the draw-works motor is 4.36 hp
Explanation:
Given that,
600 lb of weight of the drill pipe 4 ft/s constant velocity of the motorM power output of the motorAs the problem given, the cable is tied of the top on the oil rig and it wraps around the lower pulley and the top pulley. So, we will be using the formula below:
\( \boxed{\rm{2s_p + s_M = l}} \)Differentiate it but with respect to the time. Therefore,
\( 2v_p +v_M = 0 \)Thus,
\( V_M = -2v_p = -2(-4) = 8 \ ft/s \)Thus, the power output should be
\( P = Fv = \bigg(\frac{600}{2}\bigg) \cdot 8 = 2400 \ lb \cdot ft/s = \frac{2400}{550} = 4.36 \ hp \)
\( \therefore \) The power output of the draw-works motor is 4.36 hp
Engine vacuum is being discussed. Technician A says that when the engine is operating under light loads, engine vacuum is low. Technician B says that engine vacuum is high when the engine is operated under heavy loads. Who is correct?
a. A only
b. B only
c. both A and B
d. neither A nor B
Answers
Technician A id correct that when the engine is operating under light loads, engine vacuum is low.
Engine vacuum is a measure of the difference in pressure between the intake manifold and the outside air. When the engine is operating under light loads, the throttle is nearly closed, and there is less air flowing into the engine. This results in a lower intake manifold pressure, which translates to lower engine vacuum. On the other hand, when the engine is operating under heavy loads, the throttle is open wider to allow more air into the engine. This results in a higher intake manifold pressure, which translates to higher engine vacuum. Therefore, the correct answer is a. A only.
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