# A Dynamic Approach for Faster Performance Measurements on Hydraulic Turbomachinery Model Testing

^{1}

^{2}

^{*}

## Abstract

**:**

## Featured Application

**Reducing the time required to assess or improve the performances of hydraulic machines is a crucial aspect for small-hydro applications. Indeed, the investments for applied research and development for this type of technologies are limited. In this paper, an alternative approach to measure the performance is evaluated and came out to be up to ten times faster than standard methods.**

## Abstract

## 1. Background

^{−1}, a head of 15 mWC on each runner and a rotational speed of 3000 min

^{−1}for both runners. The prototype turbine was manufactured and tested on the HES-SO Valais//Wallis—Switzerland test rig [12] to assess its performances.

- (i)
- reduce significantly the time necessary to draw the complete efficiency characteristics of a hydraulic machine;
- (ii)
- detect hydrodynamic instabilities within the operating range of the machine;
- (iii)
- establish an alternative/complementary faster procedure for hydraulic efficiency measurements.

## 2. Methodology

_{m}and the pressure at the low side of the machine. With these measured parameters, the E-Q operating range along with the corresponding hydraulic efficiency and the cavitation behavior can be evaluated. In addition, measurements of the runaway characteristic, different loading forces, pressure fluctuations and observations on the draft tube vortex rope development come to complete a typical set of tests [20]. Finally, the dimensionless characteristics (e.g., using the discharge–energy coefficients φ-ψ, or the speed–discharge factors N

_{ED}-Q

_{ED}, etc.) retrieved on the reduced-scale model present the advantage of being valid for the target prototype as well, respecting both the geometric and hydraulic similitude laws.

#### 2.1. Classical Standard Static Measurements Approach

_{i}, using combinations of turbine runners’ speeds (N

_{A}and N

_{B}) while keeping constant the speed ratio between the two runners, α

_{i}. For each selected testing head, the result is a tri-dimensional efficiency hill-chart, figured in the right side of the first step. Then, in the second step, for each testing head, the variations of efficiency η with the discharge Q and with the head H are drawn for all sets of constant runners’ speed ratio, and their envelope is calculated. In the third phase, the previously obtained envelopes are used to construct the final full 3D hill-chart of the machine by surface interpolation.

#### 2.2. Alternative Dynamic Measurements Approach

_{p1,2,3 i}of the test rig recirculating pumps, the turbine runners speed is changed from zero to maximum and back to zero, while maintaining a constant speed ratio. The resulting efficiency hill-chart displayed in the right side is obtained this time not from discrete points, but from curves. Moreover, the amount of information acquired in a relatively short time is much more important compared to the few points measured by the static point-by-point method. Then, in the second phase, for each recirculating pumps’ speed, the variations of efficiency η with the discharge Q and with the head H are drawn for all sets of constant turbine runners speed ratio, and their envelopes are calculated. One may state here the completely different variation of the efficiency with the head compared to the classical static method due to the intersection of recirculating pumps’ characteristic with the characteristic of the turbine. Finally, in the third phase, the obtained envelopes are again used to construct the final full 3D hill-chart of the machine by surface interpolation.

## 3. Experimental Setup

#### 3.1. HES-SO VS Hydraulic Testing Infrastructure

^{3}/h and a maximum pressure of 160 mWC. The testing variable-speed model is placed in the upper part of the circuit, upstream a free-surface pressurized reservoir. The latest allows simulating a given setting level of the model, either positive or negative, and thus investigating also the cavitation performances. The operation of the test rig is ensured by an automatic system. Its customized LabVIEW

^{®}interface allows for real-time measurements and displays the instantaneous values of pumps’ speed, discharge, testing head, water temperature, Thoma number etc. The autonomous regulation system can keep constant the value of the pumps’ speeds, the testing head or the discharge. Finally, the wireless communication architecture between the hydraulic test rig and the measurement/monitoring systems (e.g., testing model control system) ensures safe centralization of data, storage and sharing, Hasmatuchi et al. [12].

#### 3.2. Case Studies

#### 3.2.1. Microturbine with Counter-Rotating Runners-Bulb Version

^{3}/h and a head of 20 mWC), for a ratio α = N

_{B}/N

_{A}= 1 between the runners absolute rotational speed, its hydraulic efficiency, obtained by numerical simulation, reaches 85% (Biner et al. [22], Münch-Alligné et al. [9]). The optimal operation of the turbine is ensured by the relative rotational speed between the two runners along with their absolute rotational speed. Further, the runners are driven by two independent electrical generators specially designed for this turbine, Melly et al. [23], placed into the upstream and downstream bulbs respectively. Two frequency converters are used to drive the variable-speed electrical generators at the desired constant rotational speed value, whatever the sign of the mechanical torque. Finally, for each runner, an incremental encoder, used mainly for the rotational speed driving, along with a torque meter ensure the mechanical power measurements. A sealed magnetic coupling separates the wet and the dry regions of the machine to protect the embedded instruments.

#### 3.2.2. Multi-Stage Centrifugal Pump-as-Turbine (PAT)

#### 3.3. Instrumentation

_{S}respectively and four additional capacitive absolute pressure transducers for the static pressure at the wall M

_{1,2,3,4}. The latest are connected through wall static pressure collectors, as may be seen in Figure 4. A PT100 transducer for the water temperature T and three optical tachometers for the rotational speed of the recirculation pumps N

_{p1,2,3}come to complete the list of instruments.

#### 3.4. Employed Testing Protocol

## 4. Results

_{h-elec}can be expressed as the product between the hydraulic-to-mechanical efficiency η

_{h-mec}and the electrical efficiency of the generator η

_{elec}:

_{h-mec}results from the product between the hydraulic η

_{h}and the bearing efficiency η

_{m}, with the hydraulic efficiency η

_{h}including the efficiency of the disc friction η

_{rm}, the energetic efficiency η

_{e}as well as the volumetric efficiency η

_{q}. In the case of the microturbine, considering its reduced size and geometrical complexity, only the hydraulic-to-mechanical efficiency η

_{h-m}, given by the ratio between the mechanical power P

_{mec}recovered by both runners and the hydraulic power P

_{h}of the whole one-stage turbine, could be measured:

_{elec}and the hydraulic power has been measured:

#### 4.1. Influence of the Runner Speed Acceleration/Deceleration Ramp

^{−1}in the case of the microturbine, or 2000 min

^{−1}in the case of the PAT. Then, for the microturbine, considering a constant runners absolute rotational speed ratio α = 1, the runners speed was uniformly increased from 1000 min

^{−1}to 2000 min

^{−1}and then decreased back to 1000 min

^{−1}. The same procedure was applied in the case of the PAT for the range from 750 min

^{−1}to 2250 min

^{−1}. In total, 6 (for the microturbine) and respectively 4 (for the PAT) different acceleration/deceleration ramps of respectively 10, 25, 30, 40, 60, 90 and 120 s/1000 min

^{−1}have been addressed.

^{−1}.

^{−1}. The evolution of the resulting standard deviation (STD) of the efficiency fluctuation η

^{*’}

_{STD}with the speed ramp, provided in Figure 8 and Table 6 confirms this assertion. Consequently, as an acceptable compromise between the measurement time and the measurement precision (efficiency errors below 1% for both cases) a speed acceleration/deceleration ramp of 60 s/1000 min

^{−1}has been selected for the further dynamic efficiency measurements.

#### 4.2. Dynamic versus Static Measurements Results and Validation

#### 4.2.1. Results at Fixed Testing Inflow Conditions

_{p}= 1500/2000 min

^{−1}), is given in Figure 9. In the case of the discrete point-by-point method, the speed of the turbine runner(s) has been modified in steps of 250 min

^{−1}from 0 to 3000 min

^{−1}, whilst is the case of the dynamic method, it has been continuously increased, and then decreased, from 0 to 3000 min

^{−1}, and vice versa. A good agreement between the results obtained by the two methods, with a maximum error of 1% between the mean values, may be observed for both tested cases, overall operating range, including off-design conditions. In the case of the microturbine, the negative efficiency values are given by a negative mechanical torque of the runners, corresponding to the turbine brake operating mode.

#### 4.2.2. Resulting PAT 4-Quadrant Characteristic

#### 4.2.3. Resulting Full 3D Hill-Charts

_{S-D}between the two hill-chart surfaces, computed with Equation (10), are mainly due to the quality of the interpolation and due to the number and the position of the available operating points. A more refined grid of operating points for classical static point-by-point method along with a more adapted surface interpolation method should reduce these artificial differences.

## 5. Discussion

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Nomenclature

Symbols | ||

D_{ref} | [m] | Runner outlet diameter |

E | [J∙kg^{−1}] | Specific energy |

g | [m∙s^{−2}] | Gravity |

H | [m] | Head |

N | [min^{−1}] | Runner rotational speed |

N_{ED} | [-] | Speed factor |

P | [W] | Power |

P*_{ED} | [-] | Power factor (based on mechanical/electrical power) |

Q | [m^{3}∙s^{−1}] | Discharge |

Q_{ED} | [-] | Discharge factor |

T_{mec} | [N∙m] | Runner mechanical torque |

η | [%] | Efficiency |

η* | [-] | Dimensionless efficiency |

η*’ | [-] | Dimensionless efficiency fluctuation |

η*_{fit} | [-] | Fitted dimensionless efficiency |

η*’_{STD} | [-] | Efficiency fluctuation Standard Deviation |

ρ | [kg∙m^{−3}] | Water density |

ω | [rad∙s^{−1}] | Runner angular speed |

Subscripts | ||

_{A,B} | 1st, 2nd independent runners | |

_{e} | Energetic losses | |

_{elec} | Electrical | |

_{h} | Hydraulic | |

_{m} | Bearing losses | |

_{mec} | Mechanical | |

_{q} | Volumetric losses | |

_{rm} | Disc friction losses |

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**Figure 1.**Standard methodology to reconstruct the full hydraulic efficiency hill-chart of a double-regulated machine using the classical static measurements method: (

**a**) First step: measurements of several efficiency hill-charts at constant testing head H

_{i}and constant speed ratio between the two runners, α

_{i}; (

**b**) Second step: calculation of discharge-efficiency and head-efficiency envelopes for all testing heads; (

**c**) Third step: construction of the final full 3D hill-chart of the machine by surface interpolation using the previously obtained envelopes.

**Figure 2.**Employed methodology to reconstruct the full hydraulic efficiency hill-chart of a double-regulated machine using the alternative dynamic measurements method: (

**a**) First step: measurements of several efficiency hill-charts at constant rotational speed N

_{p1,2,3 i}of the test rig recirculating pumps and constant speed ratio between the two runners, α

_{i}; (

**b**) Second step: calculation of discharge-efficiency and head-efficiency envelopes for all testing recirculating pumps’ speed values; (

**c**) Third step: construction of the final full 3D hill-chart of the machine by surface interpolation using the previously obtained envelopes.

**Figure 3.**Hydraulic test rig (2016 version) of the HES-SO Valais//Wallis—Switzerland [12]. (Main characteristics: (1) Maximum head: 160 mWC; (2) Maximum discharge: ±100 m

^{3}/h; (3) Generating power: 20 kW; (4) Pumping power: 2 × 18.5 kW and 1 × 5.5 kW; (5) Maximum pumps’ speed: 3500/3000 min

^{−1}; (6) Total circuit volume: 4.5 m

^{3}).

**Figure 4.**Experimental setup of the counter-rotating microturbine and of the pump-as-turbine (PAT) for hydraulic performance measurements on the test rig.

**Figure 6.**Influence of the acceleration/deceleration ramp of the runner(s) speed on the power and on the efficiency during one forth and back cycle at fixed testing inflow conditions: (

**a**) variation of the counter-rotating microturbine mechanical power (N

_{p1,2,3}= 1500 min

^{−1}); (

**b**) variation of the PAT electrical power (N

_{p1,2,3}= 2000 min

^{−1}); (

**c**) variation of the counter-rotating microturbine efficiency (N

_{p1,2,3}= 1500 min

^{−1}); (

**d**) variation of the PAT efficiency (N

_{p1,2,3}= 2000 min

^{−1}).

**Figure 7.**Influence of the acceleration/deceleration ramp of the runner(s) speed on the efficiency fluctuation during one forth and back cycle at fixed testing inflow conditions: (

**a**) counter-rotating microturbine—constant test rig pumps’ speed of N

_{p1,2,3}= 1500 min

^{−1}; (

**b**) PAT—constant test rig pumps’ speed of N

_{p1,2,3}= 2000 min

^{−1}.

**Figure 8.**Resulting efficiency fluctuation standard deviation (STD) depending on the acceleration/deceleration ramp.

**Figure 9.**Dynamic versus static power coefficient and efficiency measurements during one forth and back cycle at fixed testing inflow conditions: (

**a**) variation of the counter-rotating microturbine power coefficient (N

_{p1,2,3}= 1500 min

^{−1}); (

**b**) variation of the PAT power coefficient (N

_{p1,2,3}= 2000 min

^{−1}); (

**c**) variation of the counter-rotating microturbine efficiency (N

_{p1,2,3}= 1500 min

^{−1}); (

**d**) variation of the PAT efficiency (N

_{p1,2,3}= 2000 min

^{−1}).

**Figure 10.**Resulting 4-quadrant characteristic curves of the PAT obtained by the dynamic measurements method: (

**a**) speed-discharge factor characteristic curve; (

**b**) speed-power factor characteristic curves.

**Figure 11.**Resulting efficiency hill-chart contours obtained by classical static point-by-point and by the dynamic measurement methods: (

**a**) counter-rotating microturbine—result of static measurements; (

**b**) PAT—result of static measurements; (

**c**) counter-rotating microturbine—result of dynamic measurements; (

**d**) PAT—result of dynamic measurements; (

**e**) contour plot scale.

**Figure 12.**Resulting efficiency 3D hill-charts obtained by classical static point-by-point and by the dynamic measurement methods: (

**a**) counter-rotating microturbine—result of static measurements; (

**b**) PAT—result of static measurements; (

**c**) counter-rotating microturbine—result of dynamic measurements; (

**d**) PAT—result of dynamic measurements; (

**e**) colour plot scale.

**Figure 13.**Validation of resulting 3D hill-charts obtained by the dynamic measurements method with the results of the classical static point-by-point method: (

**a**) comparison for the counter-rotating microturbine; (

**b**) comparison for the PAT.

**Figure 14.**Resulting contours of difference between the 3D hill-charts obtained by the dynamic measurements method compared with the results of the classical static point-by-point method: (

**a**) result for the counter-rotating microturbine; (

**b**) result in the case of the PAT.

Measured Quantity | Sensor Type | Range | Accuracy |
---|---|---|---|

Discharge (Q) | Danfoss MAGFLO MAG3100 Water electromagnetic flowmeter | 0..±100 [m^{3}/h] | ±0.5 [%] |

Head (H) | Endress and Hauser Deltabar M PMD55 differential pressure sensor | 0..16 [bar] | ±0.1 [%] |

Setting level (H_{S}) | Fuji FCX-CII Series differential pressure sensor | 0..5 [bar] | ±0.2 [%] |

Absolute static pressure (M_{1,2,3,4}) | Endress and Hauser Cerabar T PMC 131 capacitive pressure transducer | 0..10/20 [bar] | ±0.05 [%] |

Water Temperature (T) | Endress and Hauser Easytemp TMR 31 PT100 transducer | 0..100 [°C] | ±0.1 [%] |

Pumps’ rotational speed (N_{p1,2,3}) | Sick VTF180-2P42417 photoelectric proximity sensor | 0..1000 [Hz] | - |

Mechanical torque (T_{mec A,B}) | NCTE 2200 torquemeter | 0..±7.5 [Nm] | ±1 [%] |

Turbine rotational speed (N_{A,B}) | IED incremental encoder | 0..7500 [min^{−1}] | 2048 [ppr] |

Electrical power (P_{elec}) | Zimmer LMG500 precision electrical multimeter | 0..1000 [V_{trms}]0..32 [A _{trms}] | ±0.03 [%] |

PAT rotational speed (N) | Incremental encoder | 0..6000 [min^{−1}] | 4096 [ppr] |

Data acquisition and control | |||

NI CompactRIO 9074 controller | Dedicated to the control/monitoring of the test rig | ||

NI cDAQ-9174 digitizer | Dedicated to the control/monitoring of the testing model using the standard static measurements method | ||

NI cDAQ-9174 digitizer | Dedicated to the control/monitoring of the testing model for the dynamic measurements |

**Table 2.**Combinations of rotational speeds of the microturbine runners for point-by-point performance measurements.

H = 0.5/0.75/1/1.25/1.5/1.75/2/2.25/2.5/2.75/3 [bar] | |||||||||
---|---|---|---|---|---|---|---|---|---|

N_{A} [%] | N_{B} [%] | ||||||||

0 | 0 | – | – | – | – | – | – | – | – |

8.33 | 0 | 2.08 | 4.17 | 6.25 | 8.33 | 11.08 | 16.67 | 33.33 | 8.33 |

16.67 | 0 | 4.17 | 8.33 | 12.5 | 16.67 | 22.17 | 33.33 | 66.67 | 16.67 |

25 | 0 | 6.25 | 12.5 | 18.75 | 25 | 33.33 | 50 | 100 | 25 |

33.33 | 0 | 8.33 | 16.67 | 25 | 33.33 | 44.47 | 66.67 | – | 33.33 |

41.67 | 0 | 10.42 | 20.83 | 31.25 | 41.67 | 55.42 | 83.33 | – | 41.67 |

50 | 0 | 12.5 | 25 | 37.5 | 50 | 66.67 | 100 | – | 50 |

58.33 | 0 | 14.58 | 29.17 | 43.75 | 58.33 | 77.58 | – | – | 58.33 |

66.67 | 0 | 16.67 | 33.33 | 50 | 66.67 | 88.9 | – | – | 66.67 |

75 | 0 | 18.75 | 37.5 | 56.25 | 75 | 100 | – | – | 75 |

83.33 | 0 | 20.83 | 41.67 | 62.5 | 83.33 | – | – | – | 83.33 |

91.67 | 0 | 22.92 | 45.83 | 68.75 | 91.67 | – | – | – | 91.67 |

100 | 0 | 25 | 50 | 75 | 100 | – | – | – | 100 |

α = N_{B}/N_{A} [−] | 0 | 0.25 | 0.5 | 0.75 | 1 | 1.33 | 2 | 4 | ∞ (N_{A} = 0) |

**Table 3.**Combinations of rotational speeds of the recirculating pumps and of the PAT for performance measurements using the static method.

N_{p1,2,3} [%] | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|

24 | 33.33 | 41.67 | 50 | 58.33 | 66.67 | 75 | 83.33 | 91.67 | 100 | |

N_{PAT} [%] | 8.33 | 8.33 | 8.33 | 8.33 | 8.33 | 8.33 | 8.33 | 8.33 | 50 | 78 |

16.67 | 16.67 | 16.67 | 16.67 | 16.67 | 16.67 | 16.67 | 16.67 | 58.33 | 83.33 | |

25 | 25 | 25 | 25 | 25 | 25 | 25 | 25 | 66.67 | – | |

33.33 | 33.33 | 33.33 | 33.33 | 33.33 | 33.33 | 33.33 | 33.33 | 75 | – | |

41.67 | 41.67 | 41.67 | 41.67 | 41.67 | 41.6·7 | 41.67 | 41.67 | 83.33 | – | |

50 | – | 50 | 50 | 50 | 50 | 50 | 50 | 91.67 | – | |

58.33 | – | 58.33 | 58.33 | 58.33 | 58.33 | 58.33 | 58.33 | 100 | – | |

– | – | – | 66.67 | 66.67 | 66.67 | 66.67 | 66.67 | – | – | |

– | – | – | 75 | 75 | 75 | 75 | 75 | – | – | |

– | – | – | – | 83.33 | 83.33 | 83.33 | 83.33 | – | – | |

– | – | – | – | 91.67 | 91.67 | 91.67 | 91.67 | – | – | |

– | – | – | – | – | 100 | 100 | 100 | – | – |

**Table 4.**Microturbine runners rotational speed variation ranges for performance measurements using the dynamic method.

N_{p1,2,3} [%] | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|

24 | 33.33 | 41.67 | 50 | 58.33 | 66.67 | 75 | 83.33 | 91.67 | α = N_{B}/N_{A} [−] | |

N_{A} [%] | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 33.33 ÷ 100 | 75 ÷ 100 | 83.33 ÷ 100 | 91.67 ÷ 100 | 0 |

0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 41.67 ÷ 100 | – | – | – | – | 0.125 | |

0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 41.67 ÷ 100 | 83.33 ÷ 100 | – | – | – | 0.25 | |

0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 33.33 ÷ 100 | 58.33 ÷ 100 | 91.67 ÷ 100 | – | – | 0.5 | |

0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 25 ÷ 100 | 50 ÷ 100 | 75 ÷ 100 | – | – | 0.75 | |

0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 25 ÷ 100 | 41.67 ÷ 100 | 58.33 ÷ 100 | 83.33 ÷ 100 | – | 1 | |

0 ÷ 75 | 0 ÷ 75 | 0 ÷ 75 | 0 ÷ 75 | 18.75 ÷ 75 | 31.25 ÷ 75 | 50 ÷ 75 | – | – | 1.33 | |

0 ÷ 50 | 0 ÷ 50 | 0 ÷ 50 | 0 ÷ 50 | 12.5 ÷ 50 | 25 ÷ 50 | 45.83 ÷ 50 | – | – | 2 | |

0 ÷ 25 | 0 ÷ 25 | 0 ÷ 25 | 0 ÷ 25 | 6.25 ÷ 25 | 12.5 ÷ 25 | – | – | – | 4 | |

0 ÷ 12.5 | 0 ÷ 12.5 | 0 ÷ 12.5 | 0 ÷ 12.5 | 4.17 ÷ 12.5 | – | – | – | – | 8 | |

N_{B}[%] | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 0 ÷ 100 | 33.33 ÷ 100 | – | – | – | – | ∞ (N_{A} = 0) |

**Table 5.**Combinations of rotational speeds of the recirculating pumps and of the PAT for performance measurements using the dynamic method.

N_{p1,2,3} [%] | 24 | 29.17 | 33.33 | 37.5 | 41.67 | 45.83 | 50 | 54.17 | 58.33 | 62.5 |

66.67 | 70.83 | 75 | 79.17 | 83.33 | 87.5 | 91.67 | 95.83 | 100 | ||

N_{PAT} [%] | 8.33 ÷ 100 |

**Table 6.**Resulting STD values of the efficiency fluctuation depending on the acceleration/deceleration ramp.

Acceleration/Deceleration Ramp [s/1000 min^{−1}] | η*’_{STD} [%] | |
---|---|---|

Microturbine | PAT | |

10 | 2.6467 | 2.2774 |

25 | 1.1363 | - |

30 | - | 1.0995 |

40 | 0.6693 | - |

60 | 0.5369 | 0.7863 |

90 | 0.3167 | 0.6246 |

120 | 0.3213 | - |

Criterion | Microturbine | PAT | ||
---|---|---|---|---|

Static Measurements | Dynamic Measurements | Static Measurements | Dynamic Measurements | |

Testing variable | 11× testing heads | 9× pumps’ speeds | 10× pumps’ speeds | 19× pumps’ speeds |

Turbine runner(s) speed | 9× speed ratios, 13× runners speeds, 0 ÷ 100% speed range | 11× speed ratios, 0 ÷ 100% forth and back runners speed variation | 12× runner speeds, 8.33 ÷ 100% speed range | 0 ÷ 100% forth and back runner speed variation |

Total measured points/curves | >1000 static operating points | ~70 dynamic curves | ~100 static operating points | 19 dynamic curves |

Total time | ~1 men-week | ~1 men-day | ~1/2 men-day | ~1/2 men-day |

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Hasmatuchi, V.; Bosioc, A.I.; Luisier, S.; Münch-Alligné, C. A Dynamic Approach for Faster Performance Measurements on Hydraulic Turbomachinery Model Testing. *Appl. Sci.* **2018**, *8*, 1426.
https://doi.org/10.3390/app8091426

**AMA Style**

Hasmatuchi V, Bosioc AI, Luisier S, Münch-Alligné C. A Dynamic Approach for Faster Performance Measurements on Hydraulic Turbomachinery Model Testing. *Applied Sciences*. 2018; 8(9):1426.
https://doi.org/10.3390/app8091426

**Chicago/Turabian Style**

Hasmatuchi, Vlad, Alin Ilie Bosioc, Sébastien Luisier, and Cécile Münch-Alligné. 2018. "A Dynamic Approach for Faster Performance Measurements on Hydraulic Turbomachinery Model Testing" *Applied Sciences* 8, no. 9: 1426.
https://doi.org/10.3390/app8091426